Activity Report - Universität der Bundeswehr München

Transcription

Institut für Informationstechnik
Professur für Informationstechnische Systeme
Prof. Dr.-Ing. Berthold Lankl
Activity Report
May 2012 - April 2014
Digital unterschrieben von Wolfgang Hanzl
DN: c=DE, st=Bayern, l=Muenchen,
o=Universitaet der Bundeswehr Muenchen,
cn=Wolfgang Hanzl
Datum: 2014.10.08 11:05:41 +02'00'
Activity Report
May 2012 - April 2014
Publisher and Editorial Staff:
Universität der Bundeswehr München
Werner-Heisenberg-Weg 39
85577 Neubiberg
Tel.: (+49)89 6004 3630
Fax: (+49)89 6004 3641
Email: [email protected]
Website: www.unibw.de/eit3_1
Layout:
Wolfgang Hanzl
85577 Neubiberg
Print:
CopyCenterWestend
Landsberger Strasse 8
80339 München
Print run: 200
1
Preface .............................................................................................. 1
2
About the Staff .................................................................................. 3
2.1
Professur für Informationstechnische Systeme ............................ 3
Scientific Staff ..................................................................................... 3
Adjunct Professors (Lehrbeauftragte) ................................................. 3
Ph.D. Candidates ............................................................................... 3
Non-Scientific Staff ............................................................................. 3
2.2
Professur für Informationsverarbeitung ......................................... 5
Scientific Staff ..................................................................................... 5
Adjunct Professors (Lehrbeauftragte) ................................................. 5
Ph.D. Candidates ............................................................................... 5
Visiting Scientists................................................................................ 5
Non-Scientific Staff ............................................................................. 5
2.3
Activities............................................................................................ 6
2.4
Awards .............................................................................................. 7
3
Teaching ............................................................................................ 9
3.1
General Remarks .............................................................................. 9
3.2
Courses ............................................................................................ 10
Professur für Informationstechnische Systeme ................................. 10
Professur für Informationsverarbeitung ............................................. 15
3.3
Ph.D. Candidates Seminar .............................................................. 20
3.4
Bachelor Theses .............................................................................. 20
3.5
Master Theses.................................................................................. 21
I
3.6
Student Research Projects (Studienarbeiten)............................... 23
3.7
Kolloquium Informationstechnik.................................................... 23
4
Dissertations .................................................................................... 25
Kittipong Piyawanno .......................................................................... 25
Fabian Hauske .................................................................................. 26
Cong Khac Dung ............................................................................... 27
Laura Premoselli................................................................................ 28
Further Ph.D. Exams ......................................................................... 29
5
Research .......................................................................................... 31
General Remarks .............................................................................. 31
Long-Haul Optical Transmission over Few-Mode Fiber..................... 32
FEC for 100Gbps Optical Communication System ............................ 33
Digital Signal Processing and Channel Coding for
Optical Fiber Communications .......................................................... 34
Robust Free-Space Optical Communications .................................... 35
Next Generation Optical Access Systems (NGOA) ........................... 36
Signal Processing for Robust Communication over
Very Fast Fading Channels ............................................................... 37
Modeling and Measurement of Oscillator Phase Noise and Its
Impact on Communications Systems ................................................ 38
Multiple-Input Multiple-Output (MIMO)
Data Transmission System ................................................................ 39
Narrow VHF Tactical Communications .............................................. 40
MIMO and Time-Frequency Packing for
Satellite Communications .................................................................. 41
II
Secure MIMO SATCOM Transmission .............................................. 42
Information Processing in the Human Motor System:
Coordination of Cyclic and Discrete Movements ............................... 44
Improved Balance Capabilities after Intervention on the
Motor-Balance-Board (MBB) ............................................................. 45
A 3-comonent model of the control error in manual tracking
of continuous signals ......................................................................... 46
Adaptive Interference Cancelation in Abdominal Signals
for Fetal Monitoring............................................................................ 47
Human-Machine-Interaction:
The Human Operator Behavior in a Control Loop with Manual
Tracking of Continuous Random Signals .......................................... 48
Motor Control in Humans: Motor Coordination in Multitasking ........... 49
6
Publications ..................................................................................... 51
6.1
Journal Papers................................................................................. 51
6.5
Conference Papers .......................................................................... 52
6.6
Presentations ................................................................................... 56
6.7
Ph.D. Theses .................................................................................... 56
6.8
Patent Applications ......................................................................... 57
7
Miscellaneous .................................................................................. 59
9th International ITG Conference on Systems,
Communications and Coding - SCC2013 .......................................... 59
Mädchen machen Technik ................................................................ 61
Institute Excursions ........................................................................... 62
Christmas Parties .............................................................................. 64
III
Preface
Berthold Lankl
Since our last research report two
years have passed with a lot of
projects and changes.
The most severe change was
the decision of my colleague
Gerhard Bauch to leave our university and join the Technische Universität Hamburg-Harburg (TUHH).
The whole institute regretfully noticed his decision. The process of
acquiring a new person for the position of a full professor for information processing started in summer
2012. We hope, that we can fill the
gap by end of this year. In the
meantime we had to look for persons who took over the teaching.
With the help of the retired and
active colleagues Werner Wolf and
Gerhard Staude, Gerhard Bauch
himself and colleague Michel Ivrlač
from the Technische Univerität
München (TUM) it was possible to
cover at least the teaching.
One
remarkable
event in this two year
period was the conference SCC2013, which
took place in January
2013 at our university.
Gerhard Bauch and
myself had the responsibility for the local organization. A big team
of our staff was engaged in various tasks
in preparation and organization of this conference and in running it. Besides
the technical program also social
events like the visit of the famous
monastery Andechs had to be prepared and conducted. The whole
conference run very smoothly,
which was due to the engagement
of our staff, especially Michael Nebel did a great job in coordinating
numerous activities in the preparation phase as well as during the
conference.
We continued our research
activities in projects, which covered
MIMO channel characterization,
MIMO transmission systems with
the focus on efficient detection
schemes, and few mode fiber optic
transmission systems with focus on
MIMO detection algorithms. We
were also active in the area of iterative soft demodulation and decoding for fiber optic transmission
systems. Our research activity together with Coriant in fiber optic
access systems ended up in a system demonstrator, for which numerous customers of Coriant
showed interest. Also our activities
in the area of fast fading channels
for wireless systems were continued and awarded with a prize for a
master thesis. Also our research
activity in the area of satellite systems was awarded with a best student paper prize. In addition to
these ongoing research activities
we started off new research projects in the area of free space optical transmission systems together
with DLR. Another project was
started in the area of tactical VHF
radio systems with the focus on
efficient waveform design and
robust receiver concepts. Together
with the Technical University of
Dresden and the HumboldtUniversity in Berlin we started a
project funded by DFG in the area
of massive MIMO systems.
The main problem in acquiring
new projects turned out to be the
search and hiring process of new
research assistants. In the field of
teaching we still support additional
programs such as Mathematical
Engineering and Computer Aided
Engineering.
As in the past also some social
activities have been carried out by
the whole institute, such as the
yearly Betriebsausflug or the
Weihnachtsfeier, to which traditionally all former institute members
are invited. These social activities
are documented at the end of this
research report.
The success of our institute in
research and teaching activities
would not have been
possible without the
continuous support and
help by all permanent
members of the Institute of Information
Technology. Therefore I
would like to thank
them all for their support and help. Dipl.-Ing.
Karl Besthorn is running
the laboratory together
with Bernhard Börner,
Karl-Heinz Schlücker
and Johannes Schmidt. Angelika
Bauer and Hannelore Heidrich as
well as Dagmar Frendl are responsible for the office issues and
teaching material as well as for the
faculty's examination office.
A big thank goes also to all past
and present Ph.D. candidates for
their achievements and their engagement in the various research
projects. I had and have a lot of fun
working together with them.
A special thank to Professor
Bauch for his help and engagement despite his new responsibilities at TUHH.
1
2.1 Professur für Informationstechnische Systeme
Scientific Staff
Dipl.-Ing. Vito Dantona
Dipl.-Ing. Christian Hofmann (until September 2013)
Dipl.-Ing. Anselm Karl
M.Sc. Paolo Leoni
M.Sc. Adriana Lobato
Dipl.-Ing. Georg Sebald (until September 2013)
Dipl.-Ing. Stephan Ludwig (until August 2013)
Dipl.-Ing. Michael Nebel (until June 2013)
Dipl.-Ing. Daniel Schmidt (until September 2013)
M.Sc. Nora Tax (until September 2013)
M.Sc. Zifeng Wu
Adjunct Professors (Lehrbeauftragte)
Prof. Dr. phil. Harald Höge, SVOX Deutschland GmbH, Munich
Prof. Dr.-Ing. Andreas Knopp
Ph.D. Candidates
Dipl.-Ing. Christian Hofmann
Dipl.-Ing. Stephan Ludwig
Dipl.-Ing. Michael Nebel
Dipl.-Ing. Daniel Schmidt
Dipl.-Ing. Robert Schwarz
M.Sc. Nora Tax
2.1
Professur für
Informationstechnische
Systeme
2.2
Professur für
Informationsverarbeitung
2.3
Activities
2.4
Awards
Non-Scientific Staff
Angelika Bauer, secretary
Dipl.-Ing. (FH) Karl Besthorn, lab engineer
Bernhard Börner, technician
Dagmar Frendl, technician
Hannelore Heidrich, secretary
Karl-Heinz Schlücker, technician
Johannes Schmidt
3
2.2 Professur für Informationsverarbeitung
Scientific Staff
Prof. Dr.-Ing. Gerhard Bauch (until September 2012)
Priv.-Doz. Dr.-Ing. Gerhard Staude
apl. Prof. Dr.-Ing. habil. Werner Wolf (retired)
Dipl.-Ing. Thomas Delamotte
Dipl.-Math. Doris Pflüger
Adjunct Professors (Lehrbeauftragte)
Dr.-Ing. Michael Dambier, Robert Bosch GmbH, Stuttgart
Dr.-Ing. Michel T. Ivrlač, Technische Universität München, Munich
Dr. rer. nat. Dietrich Manstetten, Robert Bosch GmbH, Stuttgart
Ph.D. Candidates
Dipl.-Ing. Hans Gerisch
Dipl.-Sportwiss. Miriam Ködderitzsch-Frank
M.Eng. Puian Tadayyon (since March 2013)
Visiting Scientists
Prof. Archil Kezeli, Institute of Cognitive Neurosciences, Agricultural
University of Georgia, University Campus at Digomi,
David Aghmashenebeli Alley, Georgia.
Megi Sharikadze, Ph.D., Department of Behavior and Cognitive Functions,
Beritashvili Institute of Physiology, Georgia.
Prof. Dr. Rodica Strungaru, Ph.D.,
Politehnica University of Bucharest, Romania.
Dragoș Țarălungă, Ph.D.,
Prof. Dr.-Ing. Mihai Tarata,
University of Medicine and Pharmacy of Craiova, Romania.
Assoc. Prof. Mihaela Ungureanu, Ph.D.,
Non-Scientific Staff
Cornelia Budach, secretary (until April 2013)
Dipl.-Ing. (FH) Josef Dochtermann, lab engineer
Wolfgang Hanzl, technician
Wolfgang Weber, technician
5
2.3 Activities
Berthold Lankl
 Activities in Academic Boards
Member of Faculty
Informationstechnik.
Board
(Fakultätsrat)
Elektrotechnik
und
Member of the CAE Master study program commission.
Member of examination board for the programs:
 Bachelor of Science Electrical Engineering and Information
Technology (EIT)
 Master of Science Electrical Engineering and Information Technology
(EIT)
 Outside Activities
Member of the technical committee Information and System Theory
(Fachausschuss 5.1 Informations- und Systemtheorie) of the Information
Technology Society in the Association for Electrical, Electronic and
Information Technologies (ITG in VDE).
General Co-Chair of the Conference on Systems, Communication and
Coding (SCC), January 21-24, 2013, Munich.
Technical program committee member of ITG Conference on Source and
Channel Coding (SCC).
Gerhard Staude
 Activities in Academic Boards
Member of Faculty
Informationstechnik.
Board
(Fakultätsrat)
Elektrotechnik
und
Member of examination board for the program Master of Science in
Mathematical Engineering (ME).
Member of Scientific Coworkers Council (Konvent der Wissenschaftlichen
Mitarbeiter).
IT representative (IT-Beauftragter) of Faculty EIT
Coordinator of Module Description (Modulhandbuch) for the Master of
Science Mathematical Engineering (ME) program.
Member of committee Biosignals (Fachausschuss Biosignale) of German
Society of Biomedical Engineering (DGBMT in VDE).
Member of committee Methodology of Patient Monitoring (Fachausschuss
Methodik der Patientenüberwachung) of German Society of Biomedical
Engineering (DGBMT in VDE).
6
Werner Wolf
Member of Technical Committee Biomedical Information Engineering
(Fachausschuss 9.3 Biomedizinische Informationstechnik) of Information
Technology Society (ITG in VDE).
Member of Technical Committee Biosignals (Fachausschuss Biosignale)
of German Society of Biomedical Engineering (DGBMT in VDE).
Member of Technical Committee Methodology of Patient Monitoring
(Fachausschuss Methodik der Patientenüberwachung) of German Society
of Biomedical Engineering (DGBMT in VDE).
Member of the Program Committee of Workshop on Innovative Processing
of Bioelectric and Biomagnetic Signals, Berlin, Germany, April 2012.
Member of the Editorial Board of the journal Biomedizinische Technik /
Biomedical Engineering.
Member of the Advisory Board of Information Technology Society
(ITG in VDE).
Program Officer of the IEEE German Section: Joint Chapter Engineering
in Medicine and Biology.
2.4 Awards
Vito Dantona
Best Student Paper Award of Estel Conference, Rome, Italy, October 2-5,
2012, for the paper Dantona, V.; Delamotte, T.; Bauch, G.; Lankl, B.:
Impact of Nonlinear Power Amplifiers on the Performance of Precoded
MIMO Satellite Systems.
Christopher Lewandowsky
August 2012: AFCEA-Studienpreis, endowed with 6,000 Euro, for Olt. Jan
Christopher Lewandowsky for his Master Thesis: "Analyse und Erprobung
mehrstufiger Modulationsverfahren bei Fast-Fading" under supervision of
Stephan Ludwig and Prof. Berthold Lankl.
7
3.1 General Remarks
The Institute of Information Technology contributes courses to the bachelor and master programs of the faculty of Electrical Engineering and Information Technology (EIT) as well as to the interdisciplinary bachelor and
master programs Mathematical Engineering (ME) and the integrated master program Computer Aided Engineering (CAE). Furthermore, courses for
the interdisciplinary program Studium Plus are offered for students of nontechnical faculties. Studium Plus is a compulsory part of the education for
all students of Universität der Bundeswehr München in which they have to
take classes of other faculties.
The bachelor program Electrical Engineering and Information Technology is organized in the two branches Communications (EIT-KT) and
Power Engineering (EIT-ES). The EIT master program offers the additional
branch Security Engineering (EIT-ST).
The program Mathematical Engineering (ME) is motivated by the fact
that many fields of engineering require a deeper knowledge in certain areas of mathematics than is usually provided by engineering programs.
Therefore, ME provides engineering education with extended mathematics. Originally established by the faculty of Electrical Engineering and Information Technology (EIT) in 2004, ME has now become an interdisciplinary program jointly offered by the faculties EIT, Aerospace Engineering
(LRT), Civil Engineering and Environmental Sciences (BauV) and Computer Science (INF).
In addition to the full university, a college of applied science
(Fachhochschule) is integrated under the umbrella of UniBwM. The program Computer Aided Engineering (CAE) is a master program designed
for students of the college of applied sciences. CAE is called an integrative
master indicating that it is a joint program of the college of applied sciences departments of mechanical engineering (MB) and Electrical Engineering and Technical Informatics (ETTI) as well as their university counterparts EIT and LRT.
The lab courses offered by our institute are equipped with modern
measurement equipment in order to get the students familiar with real
hardware and up to date measurement systems. We think that it is of importance to show the link from theory to practical applications and to demonstrate, that practical problems typically need theory from more than one
discipline.
In the following list of courses provided by the Institute of Information
Technology, we indicate compulsory courses by P (Pflichtfach) and elective courses by WP (Wahlpflichtfach). All compulsory courses can also be
chosen as elective courses in other program branches.
3.1
General Remarks
3.2
Courses
3.3
Ph.D. Candidates Seminar
3.4
Bachelor Theses
3.5
Master Theses
3.6
Student Research
Projects
3.7
Kolloquium
Informationstechnik
9
3.2 Courses
Bachelor
Signale und
Kommunikationssysteme
(Signals and Communications
Systems)
Lankl with research assistants
6 ECTS
P Bachelor EIT, INF, 5. Trimester






Kommunikationstechnik I
(Communications Engineering
Part I)
5 ECTS
P Bachelor EIT-KT, 6. Trimester
P Bachelor ME, 6. Trimester






10
Description and parameters of deterministic signals (Fourier transform
and its properties in time and frequency domain, theorem of Parseval,
convolution, applications in communication engineering)
Description and parameters of stochastic signals (random variables,
stochastic processes, probability density function, cumulative density
function, expected values and moments, stationary and ergodic
processes, Gaussian processes, Laplacian processes and other typical
processes in communications engineering, autocorrelation function
and its properties, correlation time, power and energy density
spectrum, equivalent noise bandwidth, cross correlation function and
its properties, classification of signals)
Theoretical classification of systems and description of their properties
Nonlinear Systems (transfer characteristics, transformation of
probability density functions in systems without memory, linearization,
single tone analysis)
Linear time variant systems (description by a two dimensional
weighting function and impulse response, ideal sampling and sampling
theorem, reconstruction of the analog signal from samples)
Linear time invariant systems (description by an impulse response and
transfer function, step response, amplitude and phase characteristic,
phase and group delay, definition of bandwidths, time responses of
filters, tapped delay lines, linear distortions and their equalization,
transmission of ransom signals via LZI systems, Wiener-ChintchineTheorem, system autocorrelation function and power transfer function,
cross correlation between input and output signals, system properties
for white Gaussian noise, correlation time and equivalent noise
bandwidth, correlation filter and applications)
General transmission systems (description of source signal,
modulation, transmitter, channel, and receiver with signal to noise
ratios, bandwidth expansion, disturbance, modulation gain)
Analog modulation formats (amplitude and frequency modulation)
Theoretical limits for information transmission (channel capacity,
maximum modulation gain)
Pulse modulation formats (real sampling and signal reconstruction,
pulse amplitude modulation, time multiplex, pulse width and pulse
position modulation)
Pulse code modulation (principle, system bandwidth, coding and
decoding methods, analysis of distortions due to limitation and
quantization, compression and expansion characteristics, 13 segment
transfer characteristic, influence of bit errors, PCM threshold, and
modulation gain, difference pulse code modulation, delta modulation,
time multiplex and ISDN)
Digital transmission in baseband (description of transmitter, channel,
equalizer, pulse former and detection, receive pulse, eye diagram,
symbol error probability, Nyquist system, intersymbol interference,
matched filter, symbol- and bit error probabilities for Nyquist systems
with additive white Gaussian noise)








Investigations in linear and nonlinear systems
Determination of signal parameters and the transmission properties of
linear time invariant systems
Amplitude modulation
Sampling and signal reconstruction
Frequency dependence of real resistors, capacitors and inductors
Compensation circuits and band filters, neutralization
Transmission lines
Noise and distortions in transistor circuits
Grundpraktikum: Grundlagen
der Kommunikations- und
Hochfrequenztechnik
(Lab Course in Basic
Communications and High
Frequency Technology)
Lankl together with Lindenmeier
and research assistants
2 ECTS
P Bachelor EIT, 6. Trimester
11
Master
Mobile digitale Funksysteme
und –netze
(Mobile Digital Radio
Transmission Systems
and Networks)
Lankl
2 ECTS
WP Master EIT-KT, INF,
10. Trimester










Methoden der Sprach- und Bildverarbeitung
(Methods for Speech and Video
Signal Processing)
Höge
2 ECTS
WP Master EIT-KT, 10. Trimester



Praktikum Nachrichtentechnische Systeme
(Lab Course Communications
Systems)
5 ECTS













12
Basics of radio transmission and time variant channel model (fading
statistics, Rayleigh, Rice, Lognormal, WSSUS model, delay spread,
coherence bandwidth, Doppler spread, coherence time)
Basics of digital transmission
Digital modulation formats (PAM, QAM, OQAM, PSK, QPSK, OQPSK,
FSK, CPFSK, MSK, CPM, GMSK, power spectral densities, bit error
characteristics)
Equalization of frequency selective channels
Basics of coding theory (block codes, convolutional codes and Viterbi
algorithm, interleaver)
Generalization to an Viterbi equalizer
Diversity and access schemes
System planning aspects (cellular concept, interference, cell splitting)
Example GSM
3G and 4G mobile radio systems
Introduction to speech and video signal processing
Emphasis to image and speech recognition
Concepts of classical signal theory as well as concepts based on artificial intelligence
Concepts for feature extraction
Classification
Fourier transform and filtering for one and two dimensional signals
Application of the methods to practical problems
Linear systems (measurement of impulse response and amplitude and
phase response)
Nonlinear systems (measurement of transfer characteristic and spectral behavior, determination of intermodulation parameters by the two
tone method)
Sampling (measurements of signals in the time domain, and the corresponding spectra)
Stochastic signals (characterization of linear systems using stochastic
input signals and cross correlation)
Amplitude modulation (Measurement of time signals and spectra, demodulation, measurement of characteristic parameters, transmission of
speech audio signal)
Frequency modulation (Measurement of time signals and spectra, demodulation, measurement of characteristic parameters, transmission of
speech audio signal)
Pulse-Code-Modulation (measurement of quantized time signals, influence of compression, uniform and µ-law quantization and channel disturbances)
Digital data transmission (carrier modulated BPSK and QPSK, bit error
rate curves with and without error correction codes, carrier phase and
timing phase influences)
Speech signal processing (Source coding algorithms for speech signals, comparison of different algorithms)





















Basics of parameter estimation and synchronization in the AWGN
channel
Signal model and stochastic description of signals and signal parameters
Classification of estimation methods and estimators: pilot-symbol
based, decision directed, feedforward and feedback structures
Cramer-Rao bound as a theoretic performance measure
Description of the elementary synchronization tasks in transmission
systems (carrier and clock, frequency and phase, channel estimation)
Exemplary estimation methods for various synchronization parameters
with respect to the modulation format (PSK, QAM) and analysis of their
performance and effort
Introduction to phase locked loops
Excursion to further estimation problems: direction of arrival estimation
and estimation of signal parameters with parametric (subspace) algorithms (ESPRIT, nonlinear least squares) or with nonparametric methods (periodogram, beamforming)
Excursion to channel estimation in flat and frequency selective channels including maximum-likelihood-channel-estimation
Simulations in MATLAB (partially provided by the students)
Parameterschätzung und Synchronisation
(Parameter Estimation and Synchronization)
Knopp
2 ECTS
Basics of probability theory (conditioned PDF, Bayes theorem)
Signal space representation (base function description, irrelevance
theorem, vector and correlation demodulator)
Detection basics (Maximum-a-posteriori and maximum-likelihood detection, minimum Euclidean distance, signal constellations and efficient
constellation design)
Union bound as an estimation for error probability
Optimal receivers with intersymbol interference (influence of colored
noise, symbol- and sequence estimation)
Reliability information (likelihood ratio), basics of information theory
Nachrichten- und
Informationstheorie
(Communication and
Information Theory)
Lankl
3 ECTS
P Master ME, 10. Trimester
Digital signal transmission in baseband (Nyquist systems, intersymbol
interference, matched filter, additive white Gaussian noise, symbol and
bit error probabilities)
Carrier modulated digital transmission (bandpass signals and systems
in the equivalent baseband, analytic signal and Hilbert transform, linear
digital modulation formats QAM, PSK, OFDM, SC-FDE, signal constellations and eye diagrams, symbol, error probabilities, guard interval
and cyclic prefix for OFDM, spread spectrum, DS-CDMA)
Bounds from information theory and basic coding theory (channel capacity, bandwidth efficiency, error detection and error correction, classification in block and convolutional codes, binary block codes, error
correction and residual error probability, linear cyclic binary block
codes, coding by polynomial division, syndrome and error detection
and correction)
BCH codes, coding and decoding, Galois fields
Synchronization for clock, carrier and frame
Kommunikationstechnik II
(Communications Engineering
Part II)
5 ECTS
P Master EIT-KT, 9. Trimester
P Master ME, 9. Trimester
WP Master EIT-ST, 9. Trimester
13
Übertragungssicherheit
(Secure Transmission Systems)
Lankl together with Lindenmeier
3 ECTS
P Master EIT-ST, 10. Trimester
P Master CAE
14
Improvement of transmission security on the physical level (Lindenmeier)
 Implications on the physical channel (noise, fading, jamming)
 Electromagnetic coupling, feed through and decoupling measures
 Shielding and filtering, noise sources and countermeasures
 Antenna diversity and intelligent antennas
System aspects for improvement of transmission security (Lankl)
 System description and basic countermeasures against jamming
 Secure transmission channels and jamming resistant transmission
methods (direct sequence spread spectrum, frequency hopping)
Professur für Informationsverarbeitung
Bachelor
This basic course for all students of the faculty is designed to ensure a
fundamental knowledge in Digital Design for the subsequent courses in
the curriculum, which compensates for different school syllabuses. Topics
of the course are:
 Propositional logic
 Number representation
 Set theory
 Boolean algebra
 Sequential circuits
 Combinatorical circuits
 Automata theory







MATLAB work environment
Introduction to matrix-based programming
Visualization and graphics
Flow control
Modular programming
Data types and -structs
User interfaces and dialogs
Digitaltechnik
(Digital Technology)
Bauch / Wolf
with Reiners
5 ECTS
P Bachelor EIT, 1.Trimester
MATLAB basics
Staude
2 ECTS
P Bachelor ME, 2. Trimester
WP Bachelor EIT, 7. Trimester
This Blended Learning course as a subsidiary subject addresses
 Automation and Controls Concepts in production processes
 History of PLC in automotive manufacturing, rewiring of hard-wired
control panels against reprogramming of digital computers
 System concept of PLC, cyclic program execution, I/O-interfaces, requirements for severe environmental conditions
 Standard IEC 61131, different available programming languages
 Safety requirements, especially for human operators
 Training of STEP7-programming (8 lectures)
SPS - Eine Einführung in das
Konzept und die Programmierung von Speicherprogrammierbaren Steuerungen
(PLC - An Introduction to the
concepts and the programming
of Programmable Logic
Controller)
Wolf
2 ECTS
WP Bachelor EIT
Microcontrollers (MCU) as a widely used element in customer products
(e.g., a high level class car is equipped with ca 300 MCUs) represent a
specific class of digital automata. Since their application mostly concerns
digital process control, the course includes an introduction to realtime data
processing, but main issues were concepts of digital automata, their realtime behavior and their programming in Assembler. Specifically, the following topics are addressed:
 Introduction to basic design of digital automata
 MCU architecture, I/O interfaces, number crunching subunits, maintenance support elements, industrial buses (IIC, CAN)
 programming in assembler
 Realtime control concepts (interrupt)
 A PC-based program development environment for the MCU 68HC12
(MC912DG128A) supporting a MCU demonstrator card
 Debugging of assembler programs
 Basic training of MCU-programming (8 self-learning lectures)
Architektur und Programmierung von Mikrocontrollern (MCU)
(An Introduction to the architecture and programming of Microcontrollers)
Wolf
2 ECTS
WP Bachelor EIT
15
Master
Signalverarbeitung
(Signal Processing)
Staude with Delamotte
4 ECTS
P Master EIT-KT, 1.Trimester
P Master ME-VSK, 1. Trimester
WP Master EIT, ME, INF-ET












Introduction to digital signal processing
Classification of signals
Description of discrete-time signals, discrete linear time-invariant (LTI)
systems
Review of Fourier series, Fourier transform, Laplace transform, sampling theorem
Discrete-time Fourier transform (DTFT)
z-transform
Discrete random variables and random processes, correlation functions and correlation matrices, power spectral density
Discrete convolution
Digital filter structures
Adaptive filters: MMSE criterion, Wiener filter, orthogonality principle,
linear prediction, system identification, LMS and RLS algorithm
Discrete Fourier transform (DFT)
Fast Fourier transform (FFT)
Applications of the Discrete Fourier Transform (DFT): Interpolation,
fast convolution with overlap-add and overlap-save method
Spectrum estimation using the DFT: Leakage effect, window types
Estimation of autocorrelation sequences and power spectrum density:unbiased and consistent estimators, cyclic correlation, Rader
method, periodogram, correlogram, Bartlett method, Welch method
Parametric estimation methods
Spectral estimation with Multiple Signal Classification (MUSIC)
Review of matrix computation and decomposition methods
(Information Processing)
Ivrlač
4 ECTS
WP Master EIT, ME, INF-ET

Grundlagen der
Signalverarbeitung
(Fundamentals of
Signal Processing)
Staude
2 ECTS
P Master EIT-ST, 1. Trimester
WP Master EIT






Description of discrete-time signals, discrete linear time-invariant (LTI)
systems
Review of Fourier series, Fourier transform
Discrete random variables and random processes, correlation functions and correlation matrices, power spectral density
Discrete convolution
Digital filter structures
Adaptive filters: MMSE criterion, Wiener filter, orthogonality principle
Digitale Signalverarbeitung
(Digital Signal Processing)
Staude
5 ECTS
P Master CAE-SuV, 2.Trimester
WP Master CAE









Sampling Theorem and quantization
Fundamentals of probability theory and random processes
Review of Fourier series, Fourier transform
Fast Fourier transform (FFT)
linear-time invariant (LTI) systems
principles of digital filters
16


































Introduction to channel coding
Basics from information theory: Discrete memoryless channel models,
channel coding theorem, channel capacity
Simple block codes: Repetition code, single parity check code,
Hamming code
Description of block codes: Generator and parity check matrix, generator polynomials, code rate, Hamming distance, Hamming weight,
bounds on the minimum Hamming distance, linear codes, systematic
and non-systematic encoders
Low density parity check (LDPC) codes
Factor graphs
Decoding principles: Syndrom decoding, maximum likelihood (ML)
decoding, maximum a-posteriori probability (MAP) decoding,
a-posteriori probability (APP) decoding, hard decision and soft
decision decoding, soft-in soft-out decoding, log-likelihood ratios,
extrinsic information, message passing decoding, iterative decoding
Principles of analytical performance evaluation and performance
evaluation by computer simulation
Convolutional codes, Viterbi decoding
Rate-compatible punctured codes, automatic repeat request (ARQ)
Concatenated codes and iterative (turbo) decoding
Principle of coded modulation
Channel codes in commercial systems
Moderne Verfahren der Kanalcodierung und Decodierung
(Modern Channel Coding and
Decoding Methods)
Bauch with Pflüger and Delamotte
3 ECTS
P Master EIT-ST, ME-MMP,
3.Trimester
WP Master EIT, CAE
Introduction to Source Coding: Source Coding Theorem, Basic Source
Codes (Huffman, Lempel-Ziv, Shannon-Fano)
Introduction to channel coding
Basics from information theory: Discrete memoryless channel models,
channel coding theorem, channel capacity
Simple block codes: Repetition code, single parity check code, Hamming code
Description of block codes: Generator and parity check matrix, generator polynomials, code rate, Hamming distance, Hamming weight,
bounds on the minimum Hamming distance, linear codes, systematic
and non-systematic encoders
Low density parity check (LDPC) codes
Factor graphs
Decoding principles: Syndrom decoding, maximum likelihood (ML)
decoding, maximum a-posteriori probability (MAP) decoding,
a-posteriori probability (APP) decoding, hard decision and soft
decision decoding, soft-in soft-out decoding, log-likelihood ratios,
extrinsic information, message passing decoding, iterative decoding
Principles of analytical performance evaluation and performance
evaluation by computer simulation
Convolutional codes, Viterbi decoding
Rate-compatible punctured codes, automatic repeat request (ARQ)
Concatenated codes and iterative (turbo) decoding
Principle of coded modulation
Quellen Codierung und
Kanalcodierung
(Source Coding and
Channel Coding)
Bauch with Pflüger and Delamotte
5 ECTS
WP Master EIT, ME
17






Embedded System Overview
Characteristics of reactive systems
Sensors and actuators
Architecture of selected microcontrollers and –processors
Standard single-purpose processors
(memory, timer, watchdog, UART, ...)
Design, simulation, and verification tools
Real-time systems
Interfaces and busses
Middleware
Hybrid and distributed embedded systems
Safety critical systems
Biosignal-Messtechnik
(Biosignal Measurement Technology)
Staude
2 ECTS
WP Master EIT, ME, LRT, INF-ET





Biomedical signals: Overview and definition
Application examples in medicine, biology and ambient-assisted living
Physiology of biological signal sources
Sensors and signal registration
Safety aspects
Biosignalverarbeitung
(Biosignal Processing)
Staude
2 ECTS
WP Master EIT, ME, LRT, INF-ET







Digital signal representation in time and frequency domains
Overview: Biosignal processing methodology
Linear and non-linear methods for signal analysis and feature
extraction
Monitoring and alarms
Pattern recognition and diagnosis support
Contest-sensitive strategies
Expert systems and artificial intelligence
Modellierung menschlichen Verhaltens in Informationsystemen
(Modelling human behavior in
information systems)
Dambier
2 ECTS
WP Master EIT, ME, LRT





Modeling fundamentals
The human black-box
Sensor technology
Modeling human control
Models human behavior in safty-critical systems
Konzepte Fahrerassistenzsystemen
(Concepts in driver assistance
systems)
Manstetten
2 ECTS
This course reports about trends in the design of commercially available
driver assistance systems. In detail, it addresses
 Introduction to basic tasks of vehicle navigation control
 Categories of available driver assistance systems
 What can accident analysis contribute to the design?
 Available sensors and their technologies (e.g. front radar)
 Design principles of the Human-Machine-Interface
 Driver Models
 Driver Monitoring
 Implications for traffic flow and drive safety
 Demonstration of a test car for conducting real driving experiments
Embedded Systems
Staude
3 ECTS
18





A hands-on training of advanced PLC application represents the main goal
of this project study independently conducted by the student in the lab
without classroom events. but under intensive supervision of the lecturer.
Students have to work on a task from process control (e.g. to establish the
program to control a small experimental robot located in a production line),
which provides insights to specific ikey issues of digital plant control by
PLC. Basic PLC knowledge (as imparted by the B.Sc. PLC course) is required to start. In detail, the project aims to train
 Exact task description by state logic diagrams and flow charts as used
in automata design
 Forming a sophisticated concept to solve the complex task by PLC
 High level PLC programming skills
 Online debugging in PLC environment
 Profound testing of the whole system and exact documentation
 Presentation of the project using MS PowerPoint
SPS - Ein Studienprojekt aus der
Automatisierungstechnik
(PLC application in an automation task - a student project)
Wolf
2 ECTS
Artificial intelligence (AI) methods (as nonlinear approaches) usually are
educated as a subsidiary subject in the “shadow” of linear system methods. Nevertheless, AI is well established in signal processing, thus this
introductory course offers the students a basic knowledge. It focuses on:
 Foundations in Artificial Intelligence (AI)
 Relationship between classical signal processing (linear systems) and
AI systems (nonlinear systems)
 Basic concepts of artificial neural networks (NN)
 Tools to design a NN for signal processing and pattern recognition
Finally, the students will conduct a lab experiment solving a pattern recognition task by a simple NN realized on a PC.
Methoden der künstlichen Intelligenz: Neuronale Netze
(Artificial Intelligence: Basics of
Neural Networks)
Wolf
2 ECTS
WP Master EIT, ME
Digital process control is introduced by presenting
 Foundations in Process Control
 Architecture of Microcontrollers (MCU)
 Real-time features of MCU, interrupt processing
 Programming of MCU in assembler
 Evaluation methods of MCUs for a given project
Finally, the students will conduct a lab experiment solving revolution frequency control of a DC motor.
Prozessdatenverarbeitung und
Microcontroller
(Real-time data processing and
Microcontrollers)
Wolf
2 ECTS










Extended graphics
Modular and recursive programming concepts
Embedded functions
Nested functions
Flexible handling of function arguments
(parameter-value combinations)
Interactive user-interfaces (callbacks)
Data import and export
Realtime data processing
Parallel processing concepts
Toolboxes
MATLAB advanced
Staude
5 ECTS
19
3.3 Ph.D. Candidates Seminar
May 07, 2013
Zifeng Wu:
Introduction to Fiber-Optic Channels
June 04, 2013
Michael Nebel:
Introduction to Iterative Decoding of LDPC, Turbo and Repeat-Accumulate
Codes
June 11, 2013
Adriana Lobato:
Long-Haul Multi-Mode Transmission
June 18, 2013
Stephan Ludwig:
The Optimum Receiver - A Tutorial
June 18, 2013
Nora Tax:
Common Receiver Architectures in MIMO Systems
July 02, 2013
Florian Moll:
Towards an empirical channel model for the optical low-Earth orbit
downlink
July 08, 2013
Vito Dantona:
Introduction to Nonlinear Power Amplifiers: System Models, Distortion
Evaluation and Countermeasures
July 22, 2013
Christian Hofmann:
MIMO Wireless Channel Modeling
3.4 Bachelor Theses
March 27, 2012
Supervisor: Nora Tax
March 4, 2013
Supervisor: Berthold Lankl
Bernhard Spinnler, Coriant GmbH
20
Robert Cederberg:
Untersuchung eines FFT-Templates in VHDL und dessen praktische Implementierung in ein FPGA
Adama Berte:
Characterisation of IQ-Mach-Zehnder Modulators
March 14, 2013
Supervisor: Vito Dantona
Patrick Plitt:
Charakterisierung der Universal Software Radio Peripheral Networked
Series in Verbindung mit MATLAB
April 12, 2013
Supervisor: Christian Hofmann
Julius Marquardt:
Analyse und Modellierung von MIMO-Funkkanälen - Rice-Faktor und
Verhältnis der Leistungen von LOS- und NLOS-Signalkomponente
Stephan Oeser:
Erstellung eines LabView basierenden Teststandes für Stellsysteme im
Kaliber <90mm
January 29, 2014
Bernhard Kipfelsberger, MBDA
Vizenz Korduan:
Beeinflussung von Reaktionszeiten durch nicht-letale Wirkmittel
June 30, 2013
Supervisor: Werner Wolf
Sebastian Sundermann:
Modularer PSK/QAM Demodulator
March 25, 2014
Supervisor: Michael Nebel
Jonas Kotschor:
Modularer PSK/QAM Detektor
March 26, 2014
Aude Martinez:
Automatische Musiktranskription
March 31, 2014
with Zifeng Wu
Patrick Wendt:
Implementierung eines Hamming Codes auf dem Xilinx Spartan-3E FPGA
April 25, 2014
Supervisor: Zifeng Wu
3.5 Master Theses
Naiyasit Phantia:
Parallelisierte Implementierung einer Taktrückgewinnung in einen FPGA
July 18, 2012
Supervisor: Daniel Schmidt
Felix Müller:
Empfängerkonzepte für MISO-Systeme
August 20, 2012
Philippe Schmeling:
Informationstheorie angewendet an Summensignalen
August 21, 2012
Robert Rostek:
Mobile Fahrzeug zu Fahrzeug MIMO Kanalmessung
August 31, 2012
Steffen Reisner:
Signalverfolger für Boundary Scan Signale an komplexen Baugruppen
September 12, 2012
Carl-Erich Bausch, Cassidian
Jan Peter Kroeske:
Analyse des optimalen Prädiktionsempfängers für DSSS-Verfahren in
Fast-Fading
September 18, 2012
Supervisor: Stephan Ludwig
Wjatscheslaw Voht:
Konzeption und Integration einer Laserscanner-basierten Messtechnik für
die Erstellung von Referenzdaten zur Verifikation dichter Umfeldrepäsentationen für Fahrerassistenzsysteme
September 20, 2012
Supervisor: Ralph Grewe,
Andree Hohm, Continental AG
Gerhard Bauch
21
September 27, 2012
Supervisor: Nora Tax
Ali Hamed Al-Btoush:
Implementierung einer Sendestrecke mit Quadraturamplitudenmodulation
in ein FPGA
September 27, 2012
Sebastian Anders:
Driver Monitoring: Lässt sich das intendierte Fahrmanöver aus Fahrdaten
bestimmen?
September 30, 2012
Hubert Winkler:
Untersuchung von Nicht-letalen Wirkmitteln mit Mehrfachreizung
August 28, 2013
Supervisor: Axel Schulte,
Gerhard Bauch
Maximilian Lange:
Evaluation der Eignung einer Low-Cost MEMS-IMU als Primärsensor zur
Flugregelung eines Mini-UAVs
August 29, 2013
Tobias Klenk:
Optimierung und Dynamisierung
Auswertung beim Tapping
August 29, 2013
with Hans Gerisch
Christian Speer:
Systemtheoretische Analyze des Querregelungsverhalten beim Führen
eines Fahrzeugs: Ist die Kognition oder die Motorik die limitierende
Größe?
August 30, 2013
22
der
Programme
zur
Biosignal-
Robert Cederberg:
Implementierung des Core-Empfängers eines MISO-Systems
August 30, 2013
Supervisor: Gerhard Staude
Benjamin Fabinger:
KFG-Fechtsimulator: Trefferdetektion mittels Hochgeschwindigkeitskamera - Entwicklung eines MATLAB-Codes zur Detektion der Trefferposition
August 30, 2013
Simon Lattrell:
Implementierung und Erprobung eines iterativen Empfängers für neue
hochstufige CPM-Wellenformen im militärischen Datenfunk
September 2, 2013
with Hans Gerisch
Hendrik Lange:
Experimentelle Analyse des Querregelungsverhalten bei deterministischen
Führungssignalen
September 20, 2013
Michael Herbert:
Optimierung eines Multitasking-Experiments mittels DIAdem® (National
Instruments Inc.) und MATLAB® (Mathworks Inc.)
Thomas Kürsten:
January 2, 2014
Supervisor: Gerhard Staude
KFG-Fechtsimulator: Trefferdetektion mittels Hochgeschwindigkeitskamera - Rekonstruktion der Trefferpositionen im Weltkoordinatensystem
3.6 Student Research Projects (Studienarbeiten)
K. Navneeth Nair: (Indian Institute of Technology, Madras)
Human-Machine-Interface: Motor timing analysis of tapping data
July 27, 2012
Valeriu Balaban: (Politehnica University of Bucharest):
Human motor control in steering: Is linear control theory an appropriate
mean to describe driver behavior? (ERASMUS project)
September 28, 2012
Alexandru-Mihai Siserman: (Politehnica University of Bucharest):
Multitasking performance in tapping experiments: Do movement parameters provide additional information on brain processes? A biosignal analysis study. (ERASMUS project)
September 28, 2012
Alexandra A. Dumitru: (Politehnica University of Bucharest):
Multitasking performance: tapping provides additional informations on
brain processes. (ERASMUS project)
September 30, 2012
Adriana G.I. Mitru: (Politehnica University of Bucharest):
Do EMG parameters provide additional information on motor coordination?
A biosignal analysis study. (ERASMUS project)
September 30, 2012
Cătălin Iustin I. Necula: (Politehnica University of Bucharest)
A Microcontroller Based Reaction Time Measurement System for Analysis
of Bimanual Control: Color specific response times. (ERASMUS project)
September 30, 2012
Stephan Oeser: Erstellung eines LabView basierenden Teststandes für
Servomotoren
October 31, 2013
Bernhard Kipfelsberger, MBDA
3.7 Kolloquium Informationstechnik
Vladimir Sidorenko: „Polar Codes“
Institute of Communications Engineering, Ulm University, Germany.
March 6, 2013
23
Kittipong Piyawanno
Carrier Synchronization in High Bit-Rate Optical Transmission
Systems
Committee
Chair: Prof. Dr.-Ing. Jochen Schein
1. Examiner: Prof. Dr.-Ing. Berthold Lankl
2. Examiner: Prof. Dr.-Ing. Henning Bülow
Friedrich-Alexander-Universität Erlangen-Nürnberg
3. Examiner: Prof. Dr.-Ing. Gerhard Bauch
Date of exam: July 17, 2012
Kittipong Piyawanno received his
PhD for his thesis entitled Carrier
Synchronization in High Bit-Rate
Optical Transmission Systems at
the Institute of Communications
Engineering (Chair Communication
Systems), by the faculty board consisting of Prof. Schein, Prof. Lankl,
Prof. Bülow (Friedrich-AlexanderUniversität Erlangen-Nürnberg)
and Prof. Bauch. After the examination procedure, Kittipong Piyawanno received the traditional
Doktorhut accompanied by a laudatio conducted by one of his research colleagues and the famous
ride over the university campus.
The focus of this project was on
carrier synchronization in high bitrate optical transmission systems.
Also this work was done in a close
collaboration with Nokia-SiemensNetworks (now Coriant). The laboratory facilities at Nokia-SiemensNetworks were used for measurements and field tests.
Carrier recovery has become
an interesting topic, because fiber
optic systems are using modulation
formats, which require coherent
demodulation. Nowadays mostly
two orthogonal polarization states
are used in order to achieve a high
bandwidth efficiency. Due to the
high carrier frequency in the order
of 200THz provided by lasers, frequency stability and phase noise of
these lasers play an important role.
In addition nonlinear phase noise
components caused in dense
wavelength division multiplex
(DWDM) systems by the fiber
nonlinearity have to be taken into
account.
Due to bit rates in the order of
more than 100Gb/s every signal
processing block in such a receiver
has to use algorithms, which allow
for parallelization. Typical operating
frequencies within ASICs are in the
order of several hundred megahertz. The clock speed of analog to
digital converters for the considered fiber optic systems are in the
range of 25 to 50GSamples/s.
Therefore a parallelization factor in
the order of more than hundred is
typically used. As a consequence
the complexity of the different
signal processing algorithms is a
very important measure. Only algorithms with moderate complexity
could be implemented in such hich
bit rate fiber optic transmission
systems.
The thesis of Kittipong Piyawanno investigates in different
approaches like differential and
multisymbol differential detection
as well as coherent concepts using
feedback and feedforward structures. Multisymbol differential detection has the drawback of a high
implementation complexity especially at higher modulation formats.
Therefore also phase estimation
concepts are investigated, which
use multiple symbols (MSPE). An
iterative multiple symbol phase
estimator (IMSPE) is proposed by
the author offering similar or even
improved performance at lower
complexity. The advantage of this
approach is also, that there is no
longer a feedback path and therefore interleaved parallelization is
possible.
Possibilities of parallelization
are investigated. The author shows
the use of superscalar architectures, which are known from microprocessors, for parallelization of
DSP blocks in fiber optic systems.
Feedforward carrier recovery
schemes like M-power and ViterbiViterbi algorithms are investigated.
Due to the importance of dual polarization schemes also polarization coupled carrier phase estimation is proposed and elaborated.
Feedback carrier recovery
schemes are somehow problematic
if parallelization has to be used.
The author proposed the usage of
the superscalar architecture within
this feedback structure to achieve a
good loop performance.
Due to high initial frequency
offsets of the lasers used for downconversion, an additional frequency
estimation and control is necessary. This aspect is also covered
in this thesis. Several approaches
using differential phases as well
as concepts like quadricorrelator
are investigated. The author proposed a schemes, which uses the
typically available frequency domain information for estimation of
the carrier frequency offset. This
frequency domain information is
typically available, because a
frequency domain equalizer is
mostly used for correction of the
chromatic dispersion of the transmission fiber.
Many of the algorithms, which
were investigated or newly developed have been experimentally
tested in the laboratories of NokiaSiemens-Networks. In this way
practical issues such as hardware
imperfections as well as the real
fiber channel could be considered
and included into the development
of new algorithms addressing
phase and frequency estimation
and tracking. Such a laboratory
environment is invaluable especially for universities.
25
Fabian Hauske
The Importance of Digital Signal Processing in High Speed
Optical Receivers: Equalization, Impairment Compensation
and Performance Monitoring
Committee
Chair: Prof. Dr. techn. Christian Kargel
2. Examiner: Prof. Dr.-Ing. Norbert Hanik
Technische Universität München, Germany
Date of exam: April 10, 2013
Dipl.-Ing. Fabian Hauske received
his PhD for his thesis entitled The
Importance of Digital Signal Processing in High Speed Optical Receivers: Equalization, Impairment
Compensation and Performance
Monitoring at the Institute of Communications Engineering (Chair
Communication Systems). The
faculty board consisted of Prof.
Kargel, Prof. Lankl and Prof. Hanik
(Technische Universität München).
After the successful examination
procedure Fabian Hauske received
his traditional Doktorhut. The reception of this Doktorhut was accompanied by a laudatio of one of
his research colleagues. The traditional ride over the university campus ended at the Uni bar, where
the successful PhD procedure was
celebrated.
This work for this thesis was
supported by Nokia-SiemensNetworks (now Coriant).
This project focused on digital
signal processing in receivers for
high speed optical transmission
systems.
Due to bit rates above 100Gb/s
digital signal processing has to
face clock rates of the analog to
digital converter in the order of 25
to 50GSamples/s. This high data
rate can only be processed digitally
using a high degree of parallelization, which in consequence limits
the complexity of the signal processing algorithms. It is usually not
sufficient to pick simple algorithms
known form radio applications,
because the channel characteristic
of a fiber channel are substantially
different. The fiber channel exhibits
linear distortions such as chromatic
distortion and polarization mode
distortion but also nonlinear distortions. Nonlinear distortions are
26
especially crucial in multicarrier
systems, which is the typical case
in fiber transmission systems. Typically hundred or even more carriers
are present on a single fiber. These
signals interact with each other and
cause impairments, which have to
be considered.
The thesis of Fabian Hauske
addresses signal processing algorithms with a focus on equalization,
but also synchronization is addressed and parameter estimation
for usage in optical performance
monitoring. Optical performance
monitoring is important for supervision of the transmission quality of
a fiber link, but especially for future
automatically configured networks.
Equalization concepts are given
for fiber optic transmission systems
using on-off-keying (OOK) and also
higher modulation formats, which
use a coherent receiver.
For the OOK modulation format
a maximum likelihood estimation
concept is presented, which used
adaptively trained estimates of
probability density functions for the
metric computation. This scheme
was adapted to BPSK and QPSK
and a complexity reduction was
proposed.
Equalization using an adaptive
linear filter was investigated and
optimized. A concept using a frequency domain equalizer in conjunction with a time domain equalizer was proposed by the author
after a complexity investigation.
The frequency domain equalizer is
mainly for the chromatic dispersion,
which causes interactions of a multitude of transmitted symbols. This
kind of distortion is very constant
over time, therefore the necessary
adaptation is limited. The time domain equalizer could be kept very
short, because only residual chromatic distortion and polarization
mode distortion has to be addressed by this equalizer.
The thesis addresses also a
timing synchronization algorithm,
based on histograms, which is very
insensitive to chromatic dispersion.
This algorithm outperforms clearly
known classical algorithms such as
square timing recovery or the
Gardner algorithm.
In addition the thesis of Fabian
Hauske addresses optical performance monitoring, Algorithms for
estimating all interesting signal
parameters such as the optical
signal to noise ratio, the chromatic
dispersion, the polarization mode
dispersion and the polarization
dependent loss are proposed.
These parameters can be used
for updating signal processing
blocks, such as the frequency domain equalizer. Another important
application is the usage of these
signal parameters for automatic
switching and routing of optical
signals in flexible networks of the
future. Software defined networks
(SDN) are investigated in many
present research activities.
Many of the algorithms proposed in this thesis have been applied and tested in the laboratory
environment of Nokia-SiemensNetworks (now Coriant). Due to
this cooperation system imperfections as well as a real channel
could be used as a test environment for the developed signal processing algorithms. This real test
environment is a very important
possibility in addition to computer
simulations, because very often the
simulation models have to be refined after measurements and subsequently provide better results.
Cong Khac Dung
Basic Timing Concepts for the Execution of Multiple Motor
Tasks: Coordination of Periodic Tapping with Discrete Tasks
Committee
Chair: Prof. Dr.-Ing. Gerhard Bauch
1. Examiner: Prof. Dr. techn. Christian Kargel
2. Examiner: Prof. Dr.-Ing. Werner Wolf
Date of exam: August 20, 2012
The Human-Machine-Interface
represents an important issue
when designing assistance devices
for humans, with Motor Coordination in Multitasking being one of the
multiple design aspects. This interdisciplinary PhD project conducted
at the Institute of Communication
Engineering as part of the Excellence Cluster ‘Cognition for Technical Systems’ (COTESYS) focuses
to determine basic limitations in
multitasking of a human operator.
Dipl.-Inform. Cong Khac Dung
successfully presented his Ph.D.
thesis to the examination board
constituted of Profs. Bauch
(chairman), Kargel and Wolf.
Numerous daily activities require
simultaneous execution of more
than one task, e.g. using a mobile
phone during walking, driving a car,
playing tennis, performing piano.
Besides multiple ongoing cognitive
processes, all these examples are
employing movements of the lower
and upper limbs as well as of the
head concurrently (not to forget
posture as a global task), thus they
have to be executed as integrated
action of the different motor components: Multi-tasking requires
motor coordination. A challenging
behavioral requirement, especially
in multitasking, is to maintain both
spatial and temporal accuracy of all
motor actions given in an emergency response revealing possible
resource bottlenecks. Laboratory
investigations on this topic often
use dual-task experiments, e.g.
bimanual tapping (tapping is hitting
a key or a surface by a finger tip)
with different instructions for the
right and left hand, respectively.
A specific case of coordination
represents the execution of a dis-
crete movement while performing
periodic movements. Mutual influences between both movements
are reported in literature: the socalled “entrainment effect” describes that discrete movements
superimposed upon periodic rhythmic movements show some dependence on the simultaneous
execution of the periodic movement. Thus, the onset of the single
discrete motor response is not simply determined by the onset of the
go-stimulus only, but the ongoing
“background” movement definitely
modulates the onset probability of
the discrete response across the
period. This behavior can be interpreted within the framework of the
minimum energy model, and it can
be observed in tremor patients as
well.
A traditional experimental setup
for tapping data measurement uses
ground contact sensors like micro
switches for the motor action observation, only; the evaluation of
the discrete events provided by
these switches is quite simple, but
the amount of obtained information
is rather limited. In this PhD project, a novel design for tapping
experiments with high-resolution
recording of the complete time
course of the finger movements
was used, and the required evaluation procedures for the biomechanical and muscle activity data (EMG)
were developed. The latter are
based on sophisticated maximumlikelihood-techniques, which again
is an example of progress in research through advanced biosignal processing.
The experimental paradigm
consists of a leading synchronization phase, followed by a continuation phase, where subjects contin-
ues the rhythm by self-paced tapping. Tapping included normal tapping, contact-free tapping, and
isometric tapping for both singletask (ST) and dual-task (DT) conditions. Mainly, finger tapping experiments were conducted, for generalization, however, also usage of
foot tapping was included. Furthermore, voice tapping and mental
tapping in combination with normal
tapping were employed.
Four different types of coordination schemes were observed in
DT tapping behavior: Marginal Tapping Interaction (MTI), Periodic Tap
Retardation (PTR), Periodic Tap
Hastening (PTH) and Discrete Tap
Entrainment (DTE); PTR and PTH
reflect dominance of the discrete
response in motor coordination,
corresponding to the phase resetting effect as described earlier in
the tapping literature. In contrast,
DTE reflected the dominant impact
of the periodic tapping on the discrete tap. In common, PTR, PTH
and DTE lead to a synchronized
execution of the two concurrent
tapping tasks (i.e. discrete tap and
periodic tapping).
An interesting aspect is given
by the final result that voluntary
saccadic eye movements can be
executed independently from periodic manual tapping, which may be
a consequence of the different neuronal pathways of the eye control.
But the spontaneous (involuntary)
eye blinks were entrained by the
(voluntary) periodic hand tapping,
which demonstrates a mutual coupling within the sensorimotor loop.
In summary, the PhD project
revealed some novel insights to
human motor coordination which
should be considered in the design
of human-machine-interfaces.
27
Laura Premoselli
Periphere Magnetstimulation zur Frührehabilitation zentralbedingter Lähmungen von Arm und Hand in den ersten
Wochen nach Schlaganfall
Committee
Chair: Prof. Dr. med. Klaus Gietzen
1. Examiner: Prof. Dr. med. Frank Lehmann-Horn
2. Examiner: Prof. Dr.-Ing. Werner Wolf
Date of exam: November 15, 2012
Activities in Biomedical Information
Technology like they are hosted at
the Chair for Information Processing imply cooperations with clinical
partners where advanced ideas
developed in basic research efforts
are applied in actual clinical problems. This PhD thesis entitled Peripheral magnetic stimulation applied in early rehabilitation of stroke
patients with upper limb spasticity
of central origin (translated) was
conducted at the Department of
Neurology (Technical University
Munich) and the Division of Neurophysiology (University of Ulm) with
the support of the Institute of Communication Engineering.
The repetitive peripheral magnetic
stimulation (RPMS) is an innovative therapeutic approach which is
applied for the treatment of central
paresis of the upper limb in the
neurological rehabilitation. Magnetic stimulation of neurons and
nerve fibres, respectively, is based
on the functional principle of neurons: they get excitatory and inhibitory input from other neurons and
receptors via ion channels, and
when the sum of all inputs exceeds
a threshold, an output impulse traveling along the axon to the subsequent neuronal circuitry is generated. Such a ionic flow in the input
channels can artificially induced by
a strong magnetic field produced
by a stimulation coil [1]. Since the
magnetic field is propagating
through bones and tissue layers,
the coil can be placed outside the
body, in this case over the muscles
affected by the stroke event. Until
now, the treatment of the complex
clinical situation after a stroke
event reveals the limits of the current medical options and possibili-
28
ties, which implies the high demand of research activities in this
field. The concept of this project
was to reestablish the sensorimotor
loop which is usually activated during a movement; the loop starts
with a motor command to the motor
cortex which is continued via the
spinal cord to the peripheral motor
neuron located within the spin,
which in turn drives the muscle.
The muscle response is monitored
by different receptor systems (e.g.
Golgi elements) and their information is transmitted to the brain levels where the muscle response is
checked for being appropriate for
the original motor command. The
outflow of this loop is damaged by
the stroke. Thus, the basic principle
of RPMS therapy is the generation
of peripherally induced proprioceptive inflow to the central nervous
system within the context of sensorimotor integration by a periodically activated coil; i.e. RPMS
should reestablish the sensory
feedback during passively performed limb movements. Previous
studies show some reduction of an
existing spastic paresis, an induction and enhancement of the voluntary motor function, and a reduction
of limb neglect. This PhD project
provides a further contribution to
the research on the effect of
RPMS, and it dwells on its utilization in the early neurological rehabilitation as a novel idea. Experiments show that the majority of the
patients subjectively perceived a
reduction of the existing neglect
and a variation of the muscle tone.
Objectively, a reduction of the neglect and a reduction of the paresis
could be most often clinically verified: comparing the level of the
electromyogram (of the affected
muscles) with the course of the
goniometric records, correlated
variations of the muscle tone were
indicative. Thus, these findings
underline the described effects of
previous studies within the scope
of muscle tone, voluntary motor
functions and cognition. Because
of the small number of patients
available in this project, however, it
could not statistically be assured to
what extent a flaccid paralysis is
influenced by RPMS, in contrast to
the proven reduction of a spastic
paresis. Despite the fact that finally
some issues are still unresolved
and unclear, the results present a
valuable contribution to the further
comprehension of the mechanisms
of action of RPMS, and they boost
motivation for further investigations. By reduction of the paresis,
normalization of the muscle tone
and removal of the neglect, RPMS
can contribute to an early perception and use of the patient's affected arm in order to counteract
an immobilization. With regard to
further studies within the context of
an optimization of the therapy in
the rehabilitation after stroke, one
could emphasize the idea to let
follow physiotherapy directly after
RPMS to intensify a possible induced voluntary motor function and
to enforce its stability. In conclusion, it is expected that all therapeutic rudiments for the mobilization after stroke are not singularly
assessed but rather they must be
combined in the context of a multimodal approach to help the patients most effectively.
[1] Barker AT, Jalinous R, Freeston IL. 1985, May 11. Noninvasive magnetic stimulation
of the human motor cortex.
Lancet 1(8437):1106-1107
Further Ph.D. Exams with Participation from the Institute of
Information Technology
Christina Hebebrand
Digitale Signalverarbeitung in kohärenten optischen Kommunikationssystemen mit mehrstufigen Modulationsformaten
1. Examiner: Prof. Dr.-Ing. Werner Rosenkranz
Christian-Albrechts-Universiät zu Kiel, Germany
Universität der Bundeswehr München, Germany
Day of defense: June 6, 2012
Martin Schlosser
Limitierende Skalierungseffekte als Grundlage für innovative Feldeffekttransistoren
Chair: Prof. Dr.-Ing. Berthold Lankl
1. Examiner: Prof. Dr. Ignaz Eisele
2. Examiner: Prof. Dr. Walter Hansch
Day of defense: October 24, 2012
Qualification procedures for an university lecturer (Habilitation) with
Participation from the Institute of Information Technolgy
Michael Ivrlač, Technische Universität München, Germany
Reviewer: Univ.-Prof. Dr. techn. Dr. h.c. Josef A. Nossek
Technische Universität München, Germany
Lehrstuhl für Netzwerktheorie und Signalverarbeitung
Reviewer: Univ.-Prof. Dr. Rudolf Mathar
RWTH Aachen University, Germany
Lehrstuhl für Theoretische Informationstechnik
Reviewer: Univ.-Prof. Dr.-Ing. Berthold Lankl,
Institute of Communications Engineering
Final talk and discussion: January 14, 2013
29
General Remarks
In the two research groups of the Institute of Information Technology, the
main focus of our research is on the lower layers, mainly physical layer
and MAC layer, of various types of communications systems: Mobile communication systems, satellite communication systems, fiber optical communication systems for long haul and access applications. The activities
include aspects of coding and security, modulation, parameter estimation
and synchronization, resource allocation, interference management, signal
processing, protocol design and system level investigations. Even though
research is completely independent from military constraints, we have
some military applications in our research portfolio. Examples are communication to cruise missiles and self-organizing networks in military convoys.
A further field of research, which has a long history at the institute, is biological signal processing and man-machine communication with a focus
on driver assistant systems.
Since the university funds only two researchers per group, most of our
projects are third party funded. We aim at a good mixture of more basic
research which is mainly funded by the Deutsche Forschungsgemeinschaft (DFG) and applied research funded by e.g. the Federal Ministry of
Education and Research (BMBF) and industry collaborations. We also
have a close collaboration with the German Aerospace Center (DLR).
Joint research in the fields of free-space optical communications as well
as interference management in satellite systems has just been initiated in
the framework of the joint faculty Munich Aerospace.
Furthermore, we have a close relationship with the Bundesamt für
Informationsmanagement und Informationstechnik der Bundeswehr (ITAmt). This gives us the chance to get access to field tests in satellite communications since the Bundeswehr is the only German satellite operator.
The institute has an outstanding laboratory equipment which allows us
to not only do theoretical investigations and computer simulations but also
proof-of-concept hardware demonstrations. Also for the verification of the
models used in theoretic work such hardware demonstrators are extremely
important. The laboratory equipment includes, oscilloscopes, RF synthesizers, network and spectrum analyzers, logic analyzers, signal and arbitrary waveform generators and in addition a driving simulator. Besides this
laboratory equipment the technical personal, which is available at the institute is very important for supporting the research projects, which include
hardware demonstrators.
For example a MIMO channel sounder has been built and used for
demonstrations and measurements in the context of our research on multiple antenna (MIMO) transmission under line-of-sight conditions. Also a
MIMO transmission system was built and used for measurements in indoor
applications using various MIMO equalizer and detection strategies. A
MIMO testbed with relay stations is in the set-up progress. Some hardware
demonstration systems were also implemented for communication links to
slow and fast moving missiles.
Research projects carried out in the field of fiber optic communications
systems are carried out in collaboration with industrial partners. The laboratory experiments in this field are conducted in the laboratories of our
industrial partners.
Furthermore, the biological signal processing laboratory provides
equipment for a variety of other experiments in the context of understanding fundamental issues of multitasking by human beings.
The following pages provide detailed descriptions of the research projects which have been carried out or started during the reporting period.
♦
General Remarks
♦
Research
31
Long-Haul Optical Transmission over Few-Mode Fiber
Project partner: Coriant GmbH (previously Nokia Siemens Networks)
Adriana Lobato
Spatial-division multiplexing in the
form of few-mode fibers has captured significant attention for longhaul optical communications, since
it allows to linearly increase the
channel capacity. This project in
collaboration with Coriant GmbH
targets to investigate different
schemes for the digital signal processing to improve the performance
of such systems.
A very appealing approach to mitigate the continuous demand on
higher data rates is spatial-division
multiplexing (SDM). It can be realized by means of few-mode fibers
(FMFs), fiber bundles or multi-core
fibers (MCF). All options can increase the channel capacity linearly by transmitting over multiple
modes, fibers or cores, respectively. Especially, FMFs (carrying
typically 6 or 12 spatial and polarization modes) have an important
advantage over the other options:
optical amplification can be done
more efficiently in terms of power
consumption.
However, before FMF-based
commercial systems are available,
a set of challenges has to be addressed. These kinds of systems
will suffer from increased receiver
digital signal processing complexity, due to the significantly longer
channel impulse response; complex mode-multiplexing and demultiplexing structures; and modedependent loss or gain (commonly
referred as loss, MDL), which originates from inline optical components (e.g. amplifiers, couplers,
switches). Recent studies show
efforts on reducing the MDL from
optical amplifiers by tuning the modal pump power and the dopant
distribution. To an extent, MDL can
also be reduced via system design:
tuning the gain per mode of the few
-mode amplifiers (FM-As) according to the loss that the different
modes experience along a span.
Nevertheless, MDL has still a detrimental effect on the system performance.
This projects aims to investigate the impact of MDL in the system performance in different scenarios. The presence of mode coupling inside the fiber is one of these
scenarios. The modes in the fiber
couple, exchange energy, as a
result of mechanical stress or imperfections during the fabrication
process. With MDL this energy
exchange will be favorable to average out the overall loss with the
transmission distance. Thus, the
stronger the mode coupling the
more convenient it is for the system
performance. Although the mode
coupling is not a deterministic process it can significantly aid the
transmission.
The project also looks into the
benefit of using different equalization schemes in the receiver. By
modulating the transmitted signal
of each mode and/or polarization
state with orthogonal frequency
division multiplexing (OFDM) the
equalization complexity using zeroforcing (ZF) or minimum mean
square (MMSE) one-tap equalizers
is smaller than for single carrier
modulation formats. However, the
performance is poor in the presence of MDL. Equalization on a
subcarrier basis, as with OFDM,
allows implementing more advanced equalization schemes like
reduced-complexity maximumlikelihood-based detection
schemes, which show a significantly higher MDL tolerance than
the ZF or MMSE equalization.
Figure 1 shows the simulation
setup, where the MDL is introduced
by the few mode amplifier (FM-A).
The signal processing blocks in the
receiver have to cope with the various imperfections of the channel
and the system components. In
order to optimize the signal processing algorithms with respect to
performance and complexity it is
planned to backup the results from
simulation also by experimental
work in the laboratories of Coriant.
This is especially important for this
project, due to new fiber models for
the FMF and optical hardware being used with different optical
modes. The available models are
not as mature as in the case of
usual single mode fiber systems
and therefore a backup or a refinement of the models used in the
simulation is very desirable.
Receiver
Figure 1: Simulation setup.
Channel
Estimation
Detection
Data
Demapping
ML-based
Detection
schemes
Parallel to serial
MMSE Equalizer
FFT
+
Serial to parallel
D
M
U
X
CP removal
MDL
Modes:
32
80 km
FM-A
synchronization
FMF
M
U
X
Disp. compensation
...
QPSKOFDM LP01
ASE
x Nspans
QPSKOFDM LP21b
Optical front end
FMF channel
Transmitter
FEC for 100Gbps Optical Communication System
Project partner: Coriant GmbH (previously Nokia Siemens Networks)
Paolo Leoni
The long-haul high-bitrate optical
communication networks forming
the backbone of the infrastructure
needs to cope with many different
impairments. while, at the same
time, sustaining the constantly
growing traffic. In collaboration with
our industrial partner Nokia Siemens Networks (now Coriant) we
investigate whether the typical assumptions made when designing
the receiver in the linear regime are
still valid when the system is operated in the non linear one.
Future ultra-long haul optical transport networks will rely on Forward
Error Correction (FEC) to broaden
the operating margins while combatting several of the signal impairments as, among the others, Amplified Spontaneous Emission
(ASE) caused by optical amplification, linear and non-linear effects
caused by the propagation such as
Self- (SPM) and Cross-Phase
Modulation (XPM), Chromatic Dispersion (CD), Polarization Mode
Dispersion (PMD), or filtering due
to optical elements such as Wavelength Division Multiplexing (WDM)
multiplexers / demultiplexers.
A promising solution is represented by the concatenation of an
inner Soft-Decision (SD) with an
outer Hard-Decision (HD) code.
The superior performance of SD
codes originates from the fact that
the decoder is presented with a
reliability measure of each bit
being 1 or 0 given that a certain
symbol (or transition) has been
observed, rather than just with logical values.
Traditionally, such probabilistic
information is calculated under the
fundamental assumption that all
impairments can be modeled as
Additive White Gaussian Noise
(AWGN); in collaboration with
Nokia Siemens Networks (now
Coriant) we inquired whether this
assumption still holds true when
such systems are not operating in
the linear regime anymore.
The experimental investigation
has been carried out in the laboratories of our industrial partner realizing a 400 km 100G system employing Differential Encoding (DE),
Polarization Division Multiplexing
(PDM), and a Quadrature Phase
Shift Keying (QPSK) constellation.
10G neighbors employing On-Off
Keying (OOK) modulation and operating at extremely high launch
powers were placed around the
central channel, which was therefore under extreme non-linear conditions. The code was a twodimensional (2D) SD Turbo Product Code (TPC), with information
word length (k) equal to 1202 =
14400 bits and code word length
(n) equal to 1282 = 16384 bits and,
hence, with a code rate (R) of
0.8789.
Figure 1 [1] shows the results
of our investigation as post-FEC Bit
Error Rate (BER) vs. pre-FEC
BER: the blue curve indicates the
results in the Back-To-Back (B2B)
case, whereas the red one shows
those after transmission in presence of 10G-OOK neighbors. As
it can be seen, the TPC suffers
from the presence of the OOK
neighbors, and becomes unstable;
this could be due to the impairments either not being white, or not
being additive, anymore.
In order to shed some light on
this problem we repeated the experiments bit-interleaving 2, 3, and
4 codewords (see again Figure 1,
various shades of red/pink), and
noticed that in the last case the
curve with 10G-OOK neighbors
overlapped again with the B2B
case. We concluded that the degradation was due to the burstiness
of the errors, a problem that can be
tackled by interleaving.
[1] P. Leoni, V.A.J.M. Sleiffer,
S. Calabrò, V. Veljanovski,
M. Kuschnerov, S. Jansen,
B. Lankl, "Impact of Interleaving on SD-FEC Operating in
Highly Non-Linear XPM-Limited
Regime", OFC 2013, paper
OW1E.6.
Figure 1: Post-FEC BER vs. pre-FEC BER in B2B and after transmission in
presence of OOK neighbors with no, 2 bits, 3 bits, and 4 bits interleaving.
33
Digital Signal Processing and Channel Coding for Optical
Fiber Communications
Doris Pflüger
Optical fiber communications have
a major part in worldwide communications. Due to the growing need
for high data rates and high-speed
transmission it is necessary to emphasize attention on signal processing and channel coding. Hereby
the special properties of optical
fiber require differential modulation,
which introduces the differential
penalty. A turbo loop between the
LDPC decoder and the demodulator reduces this penalty. We investigate a method to optimize the
LDPC code, using EXIT charts and
their geometrical properties.
Worldwide communication networks are based to an everincreasing extent on optical fiber.
Its large frequency range offers a
wide bandwidth, and its low attenuation allows transmission over
long distances of more than one
thousand kilometers. Even though
the available bandwidth of optical
fiber is very high, the exponential
growth of data traffic requires advanced modulation schemes combined with dense channel spacing
for bandwidth‐efficient transmission. Therefore the advantages of
digital signal processing and coding over compensating fiber in matters of complexity and performance
have to be exploited.
In particular a good forward
error correction is essential to guarantee the required bit error rate in
the range of 10-15. A class of codes
which are promising to satisfy
Figure 1: Joint Digital Signal Processing and Decoding is applied.
34
these requirements are low density
parity check (LDPC) codes. They
distinguish themselves by their
good error correcting and almost
capacity achieving behavior, and
by their potential for parallelization.
Some of the characteristics in
optical communications are very
different from other communication
systems. Especially for high date
rate the specific behavior of optical
fiber becomes apparent. For example hybrid systems, consisting of
neighboring channels with a data
rate of 100Gbit/s and 10Gbit/s,
suffer from phase error bursts.
They require differential modulation, which always comes at the
cost of a degradation of the bit error rate over the signal to noise
ratio, the so called differential penalty. This causes a conflict to the
goal of the forward error correction.
Therefore a joint consideration of
differential demodulation and error
correction is advisable.
An often used approach to
solve the dilemma between demodulation and decoding is to apply a feedback loop from the error
correction decoder back to the differential demodulation, see Fig. 1.
It has been shown that for certain
types of decoding algorithms, like
convolutional codes, this feedback
is an appropriate method to overcome the differential penalty.
LDPC codes are decoded iteratively themselves. Thus it is not self
-evident that the additional iteration
between decoder and demodulation causes further gain. Hereby
the optimal code design is an urgent problem to identify the relevant constraints to overcome the
differential penalty. In particular,
irregular LDPC codes are considered. Several aspects have to be
taken into account in the optimization, like the target code rate, the
error floor or the complexity.
With the help of EXIT charts,
see Fig. 2, we have set up an optimization problem to determine if
the differential penalty can be compensated. Hereby we distinguish
several cases like a pure differential case or a combined differential
and coherent case to gain flexibility
in the application of the constructed
codes. Depending on the optimization parameters, the problem is
nonlinear, and it is unknown
whether it is convex. Therefore the
standard optimization algorithms
fail. To get a complete overview we
have investigated an approximation
of the non linear cases. We use
geometrical properties of the EXIT
chart like the gradients or tangents
to construct upper and lower limits
of the optimum, see Fig. 2. Comparing and analyzing different
modulation scenarios, we have
identified the necessary parameter
combinations to overcome the differential penalty. In contrast to previous attempts, this approach is
systematic and does not depend
on try-and-error.
Figure 2: Geometrical properties of the EXIT Chart are used to construct
optimal codes.
Robust Free-Space Optical Communications
Project partner: Deutsches Zentrum für Luft– und Raumfahrt e.V. (DLR)
Zifeng Wu
„00101101…“
laser
method is a simple on-off keying of
the laser and there is comparably
little signal processing involved in
current systems. It is to be expected that FSO will experience a
similar surge in development as
fiber-optics if optical heterodyne
detection is employed in the receiver (Fig. 2). In this case, the
received optical signal is superimposed with a local oscillator (laser)
before being detected with a balanced photodiode pair. The difference of the photocurrents yields an
intermediate frequency signal containing both amplitude- and phase
modulation of the optical signal.
Optical heterodyne detection not
only provides an improved receiver
sensitivity but also the huge advantage of linear signal recovery in the
electrical domain, enabling more
efficient digital signal processing.
0 0 1 …
0 0 1 …
turbulence
TIA
ADC
photodiode
DSP
clouds, fog
signal
generator
detector
wavefront
distortions
TIA: transimpedance amplifier
attenuation
ADC: analog-to-digital converter,
DSP: digital signal processor
laser
-
TIA
received
optical signal
balanced
photodiode pair
Figure 1: FSO communication system with on-off keying signaling.
3dB
coupler
Modern optical communication
systems are designed around a
common concept (Fig. 1). A highly
coherent light source, e.g. a semiconductor laser, is modulated by
an electrical data signal to obtain
an optical transmission signal. In
fiber-based systems, the laser
beam is then launched into an optical fiber which allows for low-loss
propagation over several tens of
kilometers. If the deployment of
optical fiber is too costly or otherwise unfeasible, then a natural
alternative is to launch the collimated laser beam directly through
the air towards a receiving aperture
which focuses the beam onto a
photodetector.
The power loss experienced
due to free-space propagation will
depend on the weather conditions.
In the worst case, total obstruction
of the beam by clouds or other
objects can occur. However, there
are degradations even in clear sky:
due to the presence of atmospheric
turbulence, the air behaves as a
medium with stochastically varying
refractive index. This leads to
wavefront distortions of the beam
which manifests in scintillation, an
effect that is similarly observed in
the twinkling of stars in the night
sky. Scintillation is a problem at
Gbit/s data rates since the signal
power at the receiver aperture can
fade to unacceptable levels for
several milliseconds. This translates into a loss of several million
data bits which needs to be overcome by powerful forward-errorcorrection (FEC) techniques, possibly combined with automatic-repeat
-request (ARQ). Fast synchronization and reacquisition after such
deep fades is also required.
While the physics behind atmospheric turbulence are fairly well
understood, the most accurate
among the existing channel models
include too many parameters to be
of practical use in our scenario.
Therefore, another challenge that
remains is to find a model that is
adequate and tractable for the purposes of a communications engineer. This is another goal that we
ultimately want to pursue with our
partners at DLR.
FSO is in a very similar state
today as fiber-optic communications was in the 90s: the signaling
modulator
Free-space optical communications
(FSO) employs collimated laser
beams to transmit information directly through the air. People have
therefore referred to this technology in a tongue-in-cheek manner
as “fiber-free optical communications”. FSO offers a cost-effective
alternative to fiber-based systems
for broadband communication.
However, there are currently still
many challenges to be solved until
FSO reaches the same level of
maturity. In this project, we investigate the design of robust Gbit/s
FSO communication systems that
achieve high availability in the
presence of disturbances introduced by the free-space channel.
Figure 2: Block diagram for optical heterodyne detection.
35
Next Generation Optical Access Systems (NGOA)
Funded by BMBF
Daniel Schmidt
x(n-2)
x(n-3)
feedforward
algorithm
controller
Interp.
Interp.
Interp.
FIFO buffer
x(n-1)
delay
x(n)
sample dropping
block
Over the last years the needs for
higher data rates were growing
exponentially because of applications like P2P, audio and video
streaming, cloud computing and so
on. The bottleneck for the data on
the way to the costumers is the last
mile, which is generally denoted as
access network.
Today, the physical medium for
these access networks is either the
copper cable (DSL, TV-cable) or
the air (UMTS, LTE). But these two
mediums have one drawback:
They have a limited bandwidth and
decision
Growing demands for higher data
rates in the access networks will
raise the need for connecting the
costumers directly via optical fiber
to the core network (FTTH). The
goal of our research is to design
and optimize the digital processing
parts of the modems for such an
optical access network.
On the one hand linear and non
linear propagation effects of the
optical fiber have to be considered
and equalized, on the other hand a
parallelized architecture of the digital signal processing algorithms
have to be developed in order to
handle the high speed data rates of
those systems.
thus data speed cannot be increased arbitrarily, since the possible data rates are proportional to
the available bandwidth.
One solution for higher data
rates in the access networks is to
take optical fiber as transmission
medium, where the usable bandwidth of about 10 THz is unbeatable high compared to some hundred MHz bandwidth of a copper
cable or expensive wireless bandwidth (telephone companies paid
50 Mrd. € for 100 MHz bandwidth
in the Germany for a 20 years
license).
Optical fiber is already standard
inside the core networks of the
telephone companies. While in
Europe it is still unusual that fiber
optics are installed directly to the
costumer’s house (“fiber to the
home”, FTTH), the number of
FTTH users in some Asian countries is higher than conventional
broadband subscribers.
Using the wavelength division
multiplexing (WDM) technique,
some hundred users can be supplied with data using only one single fiber. In WDM the individual
channels do not interfere because
they are using different wavelengths of laser light and are thus
separated in frequency domain.
For optical access networks the
so called passive optical networks
(PONs) are of special interest, because they are only using passive
components inside the transmis-
Interp.
enable / disable
Block diagram of a parallelized clock recovery circuit for a NGOA receiver.
36
sion link. By that, they are saving
money compared to an infrastructure consisting of active optical
components (higher power consumption, demanding maintenance
and expensive hardware) and are
easier to adjust to new developments in the endpoint equipment.
The goal of our research is to
develop the digital signal processing parts of the transmitting and
receiving modems for such an optical access network. While the
equipment at the costumer’s site
should be able to handle just one
data stream of around one Gbit per
second, the devices at the operator’s site must process several of
those high data streams in parallel.
For the real time implementation it must be considered that actual silicon devices like FPGAs or
ASICs are clocked with only a few
hundred MHz. In order to process
rates of some Giga samples per
second several successive samples are arranged as one block and
are processed in parallel. Thus the
clocking speed of the silicon device
can be less than the sampling rate
of the system.
While for some components the
implementation in a parallelized
manner is straight forward, for others like for example the digital
clock recovery it is not. So the investigation of a parallelized architecture of the necessary algorithms
is one part of our work.
Because parallelization consumes much of chip area low complexity structures for the algorithms
have to be found in order to fit a
whole receiver into the given chip
area. This is an demanding challenge especially for the channelizer
at the operator’s site equipment
since many data streams of the
users has to be separated and
downconverted at the same time.
Together with a partner of the
industry a real-time system with the
proposed parallelized algorithms
was built and tested.
Signal Processing for Robust Communication over Very Fast
Fading Channels
Project partner: MBD.A Missile Systems
Stephan Ludwig, Anselm Karl
Robust and reliable communication
in ground-to-air scenarios departs
from general assumptions that are
common in mobile communication
systems due to its strongly timevariant multi-path channels. In an
industry cooperation with MBDA
Missile Systems, we investigate
single-user communication algorithms that allow reliable and robust
communication under such circumstances.
The for over 5 years existing cooperation with MBDA Germany has
been passed by Dipl.-Ing. Stefan
Ludwig to Dipl.-Ing Anselm Karl
during 2014.
In the considered scenarios,
the RF signal propagates from the
base station over several different
paths, caused by physical scattering, reflection and diffraction effects
to a mobile receiver and interferes
at its antenna. Communication to
fast mobile receivers (like on a
missile) results in large Doppler
shifts of the carrier frequency,
which are not constant over all
paths in general because of the
paths´ different angels of arrival.
The interference of the paths leads
to rapidly varying reception levels.
This effect is called fast fading in
general and the channel is said to
be doubly selective (in time and
frequency). Because of the high
time-variance of the channel, the
classic approach of block fading
(assuming the channel to be nearly
constant over a block of several
symbols) does not work.
The main fields of interest within
our research are:
 Under a peak power constraint,
determine the non-coherent
capacity of doubly selective
fading channels and how to
achieve that capacity
 System design that exploit the
inherent time and frequency
diversity of doubly selective
fading channels
 Algorithms for jointly estimating
the channel scattering function
and detecting
 Channel coding and spreading
in the frequency domain, in
general how to optimally use
the quiescent bandwidth spread
 Find possibilities of quickly and
efficiently testing new algorithms
In the course of the project a prototype of a data link has already
been established. It is based on an
XILINX FPGA and proprietary RF
board. In order to test new concepts faster (by skipping the FPGA
integration process) we are developing a system in which as many
as possibly components are software implemented and which is
based on low-cost commercial
components. The basic features
have already been implemented.
The system can be used for channel sounding as well.
In 2014 the existing system is
to be extended by a RAKE receiver
together with the project partner.
The rake receiver is a common
approach to use the signal energy
from different signal paths in
spread spectrum systems. For coherent modulation schemes the
rake receiver is well described in
the literature. When using incoherent modulation (as used in existing
link) it should be possibly to also
use the concept of an RAKE receiver.
In the existing link available
bandwidth was mainly invested in a
high code rate and only very moderate in DSSS. In addition spreading sequences are used, which are
much longer than one symbol (long
spreading), because these offer
better protection against eavesdropping and spoofing.
To allow a separation of the
individual paths´ components of the
received signal with little cross talk
(which is vital for the performance
of the RAKE receiver), partial
spreading sequences (part of the
sequence per symbol) with little
cross correlation and little autocorrelation (at other delays than zero)
have to be used. Sequences for
long spreading (f.i. PRN sequences) are not optimized regarding (partial) acf and ccf. So tradeoffs between security and performance and between code rate and
spreading rate have to be found.
Doubly selective fading channel / RAKE receiver.
37
Modeling and Measurement of Oscillator Phase Noise and its
Impact on Communications Systems
Michael Nebel
In nearly every communications
system, a local oscillator is used for
the up-conversion of the signal to
be sent at the transmitter and for its
down-conversion to base-band at
the receiver. Existing models of the
noisy oscillator circuit are used and
also enhanced in order to describe
the oscillator's impact on the performance of the system correctly.
Therefore, a measurement system
for phase noise based on the
method of cross-correlation was
built. The next step is to optimize
modern oscillator circuits according
to the theoretical results such that
the degradation of the system due
to phase noise is minimized. This is
also to be evaluated by measurement.
The local oscillator both at the
transmitter and at the receiver can
be a major problem if its spectral
purity is not sufficient. In practice,
the oscillator's output signal is
varying in a characteristic manner
which can be roughly classified in
slow changes of its frequency and
fast variations of its phase. In many
systems, the slow variations can
be mitigated by the receiver (by
phased-lock-loop f.ex.) whereas
the fast disruptions lead to a worse
receive quality which manifests
itself in a decreased bit error rate.
Traditionally, the behavior of a
noisy oscillator circuit is described
using a stationary linear model
(published by Leeson) which had
later been extended to a timevariant but also linear model by
Lee and Hajimiri. However, we
favor prefer the non-linear theory
developed by Kaertner and Demir
which has been shown to produce
more reliable and much more detailed prognosis on an oscillating
circuit's phase noise characteristics. They are mainly based on a
realistic modeling of both the oscillator circuit's noise sources and the
spectral noise-to-phase noise conversion. However, this theory concentrates only on the oscillator's
output signal without considering
the usage of the oscillator as part
of a system, for example as a local
oscillator within a communications
receiver. We argue that the charac-
Figure 1: the circuit diagram of the system measuring an oscillator's phase
noise (i.e. the device-under-test (DUT)) by cross-correlation is shown on the
left. The DUT's output signal is mixed down to baseband using two independent reference oscillators REF1 and REF2 synchronized to the DUT by phaselocked-loops. The result is digitized and the impact of the reference oscillators is canceled by cross-correlation.
38
teristics of the frequency mixer
basically causes the phase noise
and the amplitude noise within the
oscillator's output signal to be
mixed up: thus, the phase noise
process showing up in the receiver's constellation diagram (i.e.
digitally modulated signals are considered) is a combination of the
original phase and of the original
amplitude of the oscillator output.
The validity of this point could be
shown for a mathematical oscillator
model.
Furthermore, a system for the
measurement of phase noise in
oscillators was realized whose
layout is shown in figure 1. It
consists of two identical measurement branches A and B. In
each of them, the signal of the
oscillator under test (i.e. whose
phase noise is to be measured)
is converted down to baseband
where two reference oscillators
REF1 and REF2 are used. Both
DUT and reference oscillator have
the same frequency and a phaselocked-loop ensures that their
phase difference is 90°. Thus, in
the phase detector, the amplitude
noise component of both the DUT
and the reference oscillator is suppressed. For this reason, the output signal should consist only of
the phase noise of the DUT and
of the reference oscillators. This
result of both measurement
branches is amplified and digitized
and can subsequently be processed in a computer. Here, the two
measurement signals are crosscorrelated which removes the
phase noise originating from the
reference oscillators. Thus, only
the phase noise caused by the
DUT shows up which is contained
in both measured signals. The
realization of this approach as a
circuit made it necessary also to
cope with several special issues,
such as the extremely good isolation of both measurement brunches
to avoid cross-talk between them.
Multiple-Input Multiple-Output (MIMO) Data Transmission
System
Nora Tax
MIMO transmission systems promise higher data rates and a better
reliability for a given signal-to-noise
ratio and a fixed bandwidth. The
spectral efficiency of actual and
future mobile communications systems can be significantly enhanced
and the use of MIMO systems enables a significant power reduction
at the transmitter of any communication system. Therefore, the improvement of the IEEE 802.11
Wireless Local Area Network
(WLAN) standard (version IEEE
802.11-n) also includes the use of
several antennas at both, the transmitter as well as the receiver. The
challenge is the feasible implementation of an efficient MIMO detector
for the separation of the spatially
multiplexed data streams which is
able to achieve a near maximum
likelihood performance with a significantly reduced complexity.
To exploit the advantages given by
the use of MIMO transmission systems a good knowledge of the
channel is highly required in order
to select and improve the system
components as well as the signal
structure used for the transmission.
Our special interest is directed
towards in-room scenarios where
we have no obstruction between
the MIMO transmitter and the receiver. These scenarios are especially characterized by the presence of a strong Line-Of-Sight
(LOS) component and a determi-
Figure 1: Schnorr-Euchner enumeration with 64 QAM.
nistic channel behavior. Treating
the LOS channel model carefully,
with respect to the nature of the
wave propagation, a high bandwidth efficiency can be achieved.
For further enhancing the data
rates a higher bandwidth is
needed, resulting in a frequency
selective channel with multiple reflecting transmission paths.
These requirements implicate
additional considerations on the
dimension of channel memory.
Therefore we get a higher complexity for the decoder on the receiver side that can be reduced for
example by performing the equalization in the frequency domain with
orthogonal frequency division multiplexing (OFDM), where each subchannel can be considered as a flat
MIMO channel. Another possibility
is the use of single carrier frequency equalization (SC-FDE).
The sphere decoder algorithm
is based on a closest point search
in the lattice with reduced complexity using the Schnorr-Euchner candidate enumeration strategy as
shown in figure 1., but still with a
variable effort depending on the
channel conditions.
The implementation of an efficient MIMO reduced search sphere
decoder results in a near maximum
likelihood performance with reduced and fixed effort. Based on
an intelligent candidate selection
strategy, determined according to
pre-computed search set missing
probabilities, the MIMO decoder
outperforms some common fixed
effort decoders and results in an
efficient exploitation of the hardware resources. Some simulation
results derived by our reduced
search sphere decoder and our
OFDM reduced search sphere decoder are depicted in figure 2.
A true MIMO data transmission
demonstrator with up to 4x4 antennas at a measurement bandwidth
of 5 MHz where you can assume a
nearly frequency flat channel has
been developed fully synchronized.
The data at the receiver is recorded and processed offline.
The next-generation demonstrator should work on the basis of
FPGAs to be able to operate and
detect the data online and with a
higher measurement bandwidth.
Figure 2: Simulation results of reduced search effort decoders for sphere
decoding in a 4x4 MIMO system with 64 QAM.
39
Narrowband VHF Tactical Communications
Project partner: BAAINBw I6.1, Funkkommunikationssysteme
Vito Dantona, Christian Hofmann
Following modern advances in
modulation and coding technologies and the requirements for interoperability between different national systems, the modulation
schemes currently used for tactical
communications in the VHF band
(30-108 MHz) need to be replaced
by more efficient techniques. Con-
trary to legacy low-rate uncoded
schemes, new adaptive techniques
may offer scalable bit rates and
elevate error protection, thus allowing a flexible trade-off between
throughput and communication
range in the narrowband 25 kHz
channel.
Continuous phase modulation
(CPM) has been widely recognized
as the most promising approach for
this purpose, taking into account
the requirement of power efficiency
for field operation. Nevertheless,
the actual choice of the waveform
Figure 1: Block diagram of the SDR test equipment which was used for field
tests.
Figure 2: 3D visualization of a test drive in a mountainous scenario (near Garmisch, Bavaria). The transmitter is represented by the yellow triangle. The
receiver locations for successfully decoded data blocks and block errors are
denoted by blue and red symbols, respectively. As no channel equalizer was
used, a lot of errors occur even in the vicinity of the transmitter due to multipath propagation. [Orthophotos: Bayerische Vermessungsverwaltung –
www.geodaten.bayern.de].
40
parameters within the category of
CPM signals is still an open point.
For instance, a choice between two
-level and multilevel schemes must
be drawn. Furthermore, the waveform design is strictly connected
with the receiver complexity, which
must be kept feasible, also taking
into account impairments from realworld channels.
A measurement setup based
on the software defined radio
(SDR) approach has been developed at our institute. Due to the
flexible SDR approach, this equipment can be used for field tests of
any CPM or linear modulation
schemes, as long as the respective
transmitter and receiver are implemented in software.
A first test campaign conducted
in the summer of 2013 in different
real-world scenarios, such as urban, rural, hilly, mountainous and
forested environments, at the carrier frequency of 60 MHz yielded
important indications for the further
optimization of the modulation
schemes and the development of
respective receivers, which must
cope with impairments such as
phase noise, multipath propagation
(particularly in mountainous environments) and adjacent channel
interference.
Our current work focuses on
the design of low-complexity receivers for multilevel CPM waveforms based on iterative decoding
and robust receiver concepts towards the aforementioned impairments. Additionally a synchronization concept has to be developed,
which is well adapted to the
achieved receiver performance.
The raw data collected during the
first test campaign in the year 2013
will be used to validate the new
advances, as long as the same
waveforms are considered. At the
same time, we are performing an
optimization of the waveforms,
which will require a new test campaign.
MIMO and Time-Frequency Packing for Satellite
Communications
Funded by DFG
Thomas Delamotte
Spectrum efficiency is a major issue in satellite communications
due to the increasing data rates
requirements and the competition
with terrestrial networks. Maintaining the competitiveness of such
systems, where strong nonlinearities are present due to the use of
high power amplifiers driven close
to their saturation point for power
efficiency, requests to explore new
degrees of freedom. In our research, the space dimension,
through the multiple-input-multipleoutput (MIMO) technology, and the
frequency dimension, through timefrequency packing, are exploited.
This paves the way for even more
spectral efficient communications.
The saturation of spectrum bands
allocated to satellite communications and the need for power efficiency due to limited power resources in the transponders restrict
the feasibility in a satellite system
of many spectral efficient strategies
encountered in terrestrial communication networks. One of the main
issue is the presence of high power
amplifiers (HPA) driven close to
their saturation point. Even though
the use of predistortion strategies
can limit the resulting impairments,
simply increasing the constellation
size to improve the data rate, as
done in the DVB-S2 standard, entails losses that could be avoided if
only constant modulus constellations (e.g. QPSK) were used. In
our works, we thus aim at exploiting other degrees of freedom than
the constellation size to increase
the spectral efficiency. These degrees of freedom are the space
and frequency dimensions.
The use of the spatial dimension is done by using the MIMO
technology which consists in deploying several antennas at the
transmitter and the receiver. Although a rich scattering environment is often assumed in MIMO
terrestrial communications, the
design of deterministic high rank
MIMO channels based on a geometrical optimization of the transmit
and receive antennas positions
also allows to achieve maximum
capacity in systems where strong
line-of-sight (LOS) signal components are observed. With such an
approach, increasing the constellation size can be avoided to improve
the data rate.
Further improvements can be
expected by combining this MIMO
technology with time-frequency
packing. The time-packing strategy, also known as faster than
Nyquist signaling, consists in
setting the signaling rate below
the Nyquist rate so as to make
use of the excess bandwidth of
practical pulse shaping filters. This
nevertheless entails strong intersymbol interference and thus requires a more complex receiver
design able to cope with this impairment. By additively reducing
the spacing between adjacent
channels in the context of multicarrier transmission, hence allowing
the presence of some inter-carrier
interference (ICI), some additional
gains can be expected. This is
known as frequency packing.
Our research concentrates on
the design of receivers for satellite
systems using both the MIMO
technology and time-frequency
packing. These receivers are de-
signed to mitigate space interference as well as the linear and
nonlinear ISI respectively resulting
from the use of time packing and
the nonlinear distortions induced by
the presence of HPAs. To reduce
the memory of the channel model
assumed to process the received
signals, a channel shortening technique is applied which aims at prefiltering the received symbols. This
reduces the number of channel
taps that should be considered to
get an accurate model of the processed symbols and thus reduce the
complexity of the received algorithms. The determination of the
channel shortening filter and the
shortened channel is done such
that the information rate of the system is maximized. The performance comparison of several strategies for a 2 x 2 MIMO system
whose antennas configuration significantly differs from the one required to achieve maximum capacity is given in Figure 1. These results enlighten the superiority of
these new approaches compared
to state-of-the-art SISO strategies
even when an optimal antenna
arrangement is not possible.
Figure 1: Achievable spectral efficiency with QPSK constellations, roll-off
α = 0.2 and IBO = 3 dB.
41
Secure MIMO SATCOM Transmission
Robert T. Schwarz, Andreas Knopp
In our research activities we were
able to find an approach for secure
communications over geostationary
satellites by means of the MultipleInput Multiple-Output (MIMO) technology with spatially distributed
ground and satellite antennas. As a
result of this approach, a possible
eavesdropper (“Eve”) on earth cannot intercept confidential messages
broadcasted by the MIMO satellite
(“Alice”), even if the eavesdropper’s antennas are positioned
within the same coverage area as
the own ground station antennas
(“Bob”). Secure MIMO SATCOM
transmission is achieved if the
channel capacity is higher between
the satellite and the own ground
station (the channel between Alice
and Bob) than between the satellite
and the interceptor’s ground station
(the channel between Alice and
Eve). As a consequence, information theory says that it is impossible
for an eavesdropper to recover the
intercepted messages if the information transmission rate of the link
is higher than its channel capacity.
We have filed for a patent about
our application which has finally
been granted in November 2013
[1]. Afterwards, we have presented
our results at the last year’s Military
Communications Conference, MILCOM, 2013 in San Diego [2], which
is a well renowned platform for
topics on security critical communications.
Keywords: Information Security,
MIMO, Satellite Communications,
Eavesdropping
Multiple Input - Multiple Output
(MIMO) transmission systems have
been known to provide increased
bandwidth efficiency and data rates
due to spatial multiplexing with
42
multiple antennas. Obeying some
practical rules and constraints,
MIMO can be used to increase the
channel capacity linearly with the
number of antennas used at the
transmitter (Tx) and receiver (Rx)
also in fixed satellite services
(FSS) applications. A linear increase and therewith the maximum
channel capacity can only be obtained with particular antenna constellations and arrangements due
to the well-known eigenvalue properties of a Line-of-Sight (LOS)
MIMO channel. Choosing the
wrong antenna arrangement therefore results in a reduced MIMO
channel capacity. This fact is very
often looked upon as a disadvantage of MIMO SATCOM since the
flexibility in ground station design
with respect to the antenna positioning and displacement is limited.
From the perspective of transmission security, the properties of the
MIMO channel capacity in SATCOM can be excellently used for
the design of satellite downlinks
that combine optimum channel
capacity between Alice and Bob
with strong transmission security.
In order to achieve these beneficial
effects, distinct locations on earth
are selected where maximum
channel capacity can be accessed,
at the same time limiting the channel capacity achievable at all the
remaining locations within Alice's
footprint. Eavesdropping is then
effectively prevented because Eve
will not be able to recover the information even if no end-to-end data
encryption is applied. Hence, data
rate reduction, which is the main
disadvantage of most encryption
schemes, can be totally avoided.
1. Bob has to find an optimal antenna configuration of his
ground terminal antennas in
relation to the antenna configuration of Alice. As a consequence, the channel between
Alice and Bob offers the maximum multiplexing gain.
2. The satellite antennas are presumably spot beams with small
coverage zones which overlap
each other to form a limited
geographical area on earth
where the maximum power flux
density (PFD) is obtained from
all satellite antennas simultaneously.
3. This limited geographical area
should be large enough – which
may be a country for example
protected by boarders – to find
an optimal antenna configuration and have to be protected
against a possible enemy intruder.
Outside this limited geographical
area it is impossible for Eve to obtain the same channel capacity as
that of the channel between Alice
and Bob even if also Eve has found
an optimal antenna configuration
and, thus, the channel between
Alice and Eve offers maximum
multiplexing gain as well. The capacity degradation for Eve is
achieved by means of a loss in the
receive signal power because of
the position-dependent PFD on
earth and, therefore, a lower signal
-to-noise ratio (SNR) at Eve’s receiver. This effect is illustrated in
fig. 1 and will be explained in the
following.
It is well-known, that the coverage of a satellite antenna on earth
(also called “footprint”) is generally
limited to a specific geographical
region where the shape of the footprint is mainly a function of antenna
dish size, dish shaping, orbit position of the satellite and viewing
angle of the satellite antenna towards the earth. An example of a
typical footprint is shown on the left
of fig. 1 with the center of coverage
(CoC) of the satellite spot beam
antenna approximately at the north
of Italy. The contour-lines refer to a
particular value of receive PFD. For
simplicity in terms of graphical illustration but w.l.o.g. the coverage
map shows constant PFD values
between the contour lines where
the maximum PFD of -110 dBW/m²
can be obtain in the vicinity of the
CoC. In this example the spot
beam antenna provides a 3 dB and
6 dB coverage zone with approximately 600 km and 1000 km in
diameter, respectively. The footprint of the second satellite antenna from Alice has to overlap the
footprint of the first antenna in order to obtain a limited geographical
area where maximum PFD can be
received from both satellite antennas simultaneously. Bob places his
receive antennas within this area
and protects this limited region
against a possible intruder.
The second aspect of this approach is the fact, that distinct inter
antenna spacing at the ground and
in the orbit are required for a maximum MIMO channel capacity in
satellite applications for FSS with
LOS channels. The right hand side
of fig. 1 shows the MIMO bandwidth efficiency as a function of the
inter antenna spacing on earth
(blue curve of the plot). In this
simulation example the inter antenna spacing of Alice’s satellite
antennas are 6 m resulting in a
minimum and optimal inter antenna
spacing of Bob’s ground terminal
antennas of about 100 km. From
fig. 1 it becomes clear that this
optimum inter antenna spacing is
periodic; a second optimum distance can be obtain at approximately 300 km. The red curve additionally considers the positiondependent PFD on earth due to the
beam patterns of the satellite antennas. In this simulation example
the CoC can be achieved at the
position 0 km at x-axis. The red
curve shows that with larger distance from the CoC the channel
capacity degrades because of SNR
reductions. If the link between Alice
and Bob provides an information
transmission rate (in Bit/s) which is
larger than the channel capacity
between Alice and Eve, finally a
bug-proof satellite connection is
achieved.
In the course of our research
work we have also analyzed strategies for Eve to mitigate the loss in
channel capacity. For Eve there
are mainly two possible approaches available: At first, Eve
could employ higher receive antenna gain in order to enhance the
receive signal-to-noise ratio. The
second approach requires a higher
number of receive antennas for the
enhancement of the channel capacity. However, in [2] we have
shown that it is comparably easy
for Alice and Bob to implement
countermeasures for both of Eve’s
strategies as long as Bob himself
must use sufficiently large antennas in order to get the minimum
signal-to-noise ratio that is required
for transmission at the desired rate.
In this case Eve would be forced to
implement even larger dish sizes
which goes along with a significant
infrastructural effort for antenna
dishes, antenna mounts and antenna pointing mechanisms. If in
addition Eve was then forced to
implement a huge number of such
complex receive antennas, say
tens of even hundreds, it would
quickly become obvious that
eveasdropping cannot be accomplished in a sensible way. Therefore, the bug-proof satellite link
based on the presented principles
of information theory finally does
not try to realize an unbreakably
secure link. Moreover, the idea is
based on the approach to increase
the effort to be spent by the intruder up to an unbearable level.
However, in difference to other
approaches, in our case the term
complexity does not address computational complexity but is related
to receiver infrastructure, particularly highly complex and costly
antenna mounts.
[1] A. Knopp, R. Schwarz, and
B. Lankl, “Verfahren und Einrichtung zur MIMO-Datenübertragung mit einer Höhenplattform, German Patent
10 2013 000 903, Nov. 28,
2013. [Online]. Available:
https://register.dpma.de/
DPMAregister/pat/register?
AKZ=1020130009030
[2] Knopp, A.; Schwarz, R.T.;
Lankl, B., "Secure MIMO SATCOM Transmission", Military
Communications Conference,
MILCOM 2013 - 2013 IEEE,
pp.284-288, 18-20 Nov. 2013,
doi: 10.1109/MILCOM.2013.56
Figure 1: Channel capacity as a function of the inter antenna distance and
additionally the position dependent receive power flux density on earth.
43
Information Processing in the Human Motor System:
Coordination of Cyclic and Discrete Movements
Gerhard Staude
Human movement control requires
coordination of different motor
tasks but actually, there is no direct
access to observe the control
mechanisms of the human motor
system. However, sometimes they
manifest themselves in the external
world as a striking phenomenon of
abnormal movement in patients
suffering from motor disorders, or,
less spectacular as a characteristic
property of observable variables
during normal movement (e.g., a
trajectory of the limb in the space,
a discharge pattern in the electromyogram (EMG) of a muscle). In
these cases, analysis of the observable electrophysiological and
biomechanical variables frequently
allows for infering on the underlying
internal mechanism.
A phenomenon frequently observed in human movement generation is rhythmic motor activity
(e.g., tremor). In this project, we
investigate the impact of rhythmic
motor activity (of either pathological
or physiological origin) on the initiation of rapid voluntary movements
and vice versa. In cooperation with
clinical and research partners, the
problem is addressed for the special example of simultaneously
executed rhythmic and discrete
finger movements (bimanual tapping).
Subjects are required to perform rhythmic constant-rate finger
tapping movements by one hand
while simultaneously responding as
quickly as possible to some imperative stimulus (go-signal) by a
single discrete tap of the other
hand (Fig. 1). Both motor tasks
cannot be performed independently
but will interact in various forms:
Some subjects tend to restart the
rhythmic pattern together with the
discrete tap. Other subjects tend to
delay the discrete tap in order to
move in phase with the cyclic task.
Most frequently, both motor tasks
mutually affect each other resulting
in a variety of different movement
patterns.
Interaction of discrete and
cyclic motor tasks is frequently
analyzed by construction of phase
resetting curves (PRCs). Tapping
events are aligned by some
reference event (usually the last
periodic tap preceding the discrete
tap) and plotted versus the locus
of the discrete tap within a cycle
of the rhythmic movement (Fig. 2).
However, biological uncertainties
like the variability of intertap intervals and reaction times together
with the cyclic nature of the observed process make the evaluation of PRC diagrams difficult
with an inherent danger of misinterpretation.
In the current framework, therefore, a model-based approach is
applied instead. Human tapping
behaviour is modelled by nonlinear
oscillators mutually coupled by
weak perturbation forces (Fig. 3).
As a particular feature of this socalled “Simple-Clock Tapping
Model”, small changes in model
parameters may lead to dramatic
changes in observable motor behaviour. Moreover, various motor
“strategies” can be described by a
single model structure and characterized by a distinct set of few characteristic parameters. Developing
reliable and unbiased estimators of
the internal variables associated
with a particular coordination pattern is a key issue of this project.
Figure 1: tapping experiment
Figure 2: phase resetting curve (PRC)
Figure 3: simple-clock tapping model
Using a smart phone, driving a car,
playing tennis, or performing piano
– most of human everyday motor
activities require interlimb motor
coordination. But we all know that
performing two or more tasks simultaneously is often difficult, let
them be either mental or motor
tasks. And even for very simple
movements, we rapidly may end up
at our limits. Where do these limits
come from? What can they tell us
about the organization of the human sensorimotor system? This
project tries to shed some light
upon the mechanisms of human
multitasking by using a psychophysiologically inspired modelbased approach.
Keywords: Human Motor Coordination, Modelling, Coupled
Nonlinear Oscillators, Tapping
Experiment
44
Improved Balance Capabilities after Intervention on the
Motor-Balance-Board (MBB)
Projectpartner: German Air Force Center for Aerospace Medicine
Miriam Ködderitzsch-Frank
Coordination and balance are essential compounds of a pilot’s success in his or her career out of a
medical and sport scientific perspective. The purpose of this study
is to investigate the effects of special balance training on the coordination system. For example the
eye-hand-coordination, the ability
of prediction and as investigated in
this study the pilot’s balance capabilities help the pilot to decide correctly in a very short time. Due to a
special training it is also possible to
improve attention and reaction
time. To register important information and to solve problems easily
the stop and go signals for movements need to be under control.
Reaction time and task switching
are in focus which can be improved
by 30% via special training.
Data for this research were collected on the MFT Board, a device
which offers different balance challenges. People have to follow instructions on a screen like standing
still or following a certain motion.
The subjects were randomly selected and divided into 3 groups:
training, short intervention and control group. They had to solve 3
tests: 1.) an initial general balance
test (T1), 2.) after training intervention on the motor-balance-board
(T2) and 3.) after prostration (100
squad jumps; T3).
The results suggest that subjects who are influenced over 3
weeks and more by a special coordination training show better results
in balance and fatigue resistance.
They perform better while working
in a group and are used to the bal-
Figure 1: Motor-Balance-Board (MBB)
ance effects. So they improve their
motor skills whenever they stand
on the MBB. It also supports the
assumption that a short practice
(min. 20 minutes on the MBB)
changes the proprioceptive system.
For pilots it can be important to
improve the fatigue system to stay
alert and clear to get necessary
information and to feel their real
position in the aeroplane. Through
specialized training it can be
achieved that disorientation gets
influenced in a positive way because of better coordination and
improved pilot’s reactions, movements and decision making.
What were the topic psychological effects? For example in a
questionnaire subjects in the training group showed that health is
more important than in the other
groups.
In the training group subjects
think that health and physical appearance are more important than
in the other two groups, also prevention is a big theme for them.
People who do nearly no regular sport in average not know how
to achieve healthy lifestyle because
they do not see prevention programs as a main issue. Referring
to public health the training group
shows the highest perceptive correlation between health an prevention. Reasons could be the health
education they received as well as
experienced health benefits of par-
ticipating in sports. The same applies to attractiveness.
Regarding balance performance the results differ from hypotheses. All three groups improved. But the learning effects
shown in the control group had an
interesting impact. So on one hand
the challenge disc and the learning
effect had a too big influence on
balance. On the other hand the
prostration time of the intervention
group was too short, since most of
the participants could not handle
100 squad jumps and finished earlier. The diagram shows that the
intervention group improved constantly but in average they could
not finish the prostration task. The
training in comparison didn’t have
the effects we expected. That could
be a hint, the focus should lie on
balance and not in an overall training concept.
After all the data drawn from
the current study design has to be
interpreted with caution. After getting rid of some design related
weaknesses more research has to
be done on the subject of balance,
since this certainly is a field of high
applicability for pilots in their daily
routine in the cockpit.
Figure 2: Progress T1 to T3, effect of MBB on balance capabilities.
45
A 3-comonent model of the control error in manual tracking of
continuous signals
Hans Gerisch, Werner Wolf
The performance of human operators acting within closed-loop control systems is investigated in a
classic tracking task using a handheld joystick.
The dependence of the control
error on the parameters ‘display
gain’ and ‘input signal frequency
bandwidth’ is investigated with the
aim of functionally specifying it via
a model.
Driving a car, operating a construction machine, navigating a ship, or
piloting an airplane – these are all
typical cases in which the human
operator is an integral component
of the overall control system. Thus,
human control contribution is essential for the overall performance,
and, consequently, an appropriate
human-machine-interface design
represents a key-factor for optimal
human-machine-cooperation.
Basically, control performance
of a human operator and his capability of visuomotor adaptation in a
tracking experiment (Fig.1) are
usually evaluated by analysing the
control error and the control delay,
both representing time domain
parameters.
Another way to describe human
tracking behaviour is given by frequency domain analysis: The operator is modelled as the controller
within a feedback loop, and the
controller is characterized by a
spectral transfer function. This approach is used by the so-called
McRuer Crossover Model originally
applied in the design of aircraft
control systems. This model allows
one to distinguish between various
styles of tracking behaviour that
cannot be discriminated simply by
the mean control error. Certainly,
the Crossover Model inspired an
in-depth global analysis of tracking
behaviour mainly focussed on stability of the control loop, but these
efforts did not further detail different components contributing to the
resulting control error.
The present investigation focuses on specifying the control
error sources. The following novel
3-component model of control error
is hypothesized: The overall control
error represents the sum of (i) the
delay-induced component, (ii) the
demand-based component for the
control processing (which is determined by accuracy tradeoffs of the
human operator in general), and
(iii) the human-tracking-limit component (i.e. the operator simply
does not try to track when the input
signal dynamics exceeds an upper
frequency limit fcrit). This human-
Figure 1: Manual tracking of continuous input signals.
46
tracking-limit component is certainly determined by individual factors, however, it is also dependent
on the kind of the input signal: fcrit is
constrained by the randomness of
the input signal, thus fcrit will be
higher for tracking a single
(predictable) sine wave.
This hypothetical error model
for tracking tasks is tested by
using noise input signals of different upper frequency boundaries
and different display gains: participants have to compensate a target
line displacement on a classical
display by an inverse joystick displacement.
Data of the experiment fit to
previous findings on human tracking behaviour; in particular, the
results reaffirm that the transfer
function of the human tracking
control-loop is limited to approximately 1 Hz, which is also in line
with the reported Nyquist frequency
of around 1 Hz based on the
Crossover Model.
First and foremost, however,
the data lend support to the hypothetical 3-component error model
and lead to the assumption that the
unpredictable signals effectively
tracked by human operators are of
a bandwidth that is less than fcrit
where 0.8 Hz < fcrit ≤ 1.2 Hz. The
questions of whether this limitation
can generally be shifted through
training, or if predictable signals
(e.g., while steering a car along a
wide curve) can be better tracked
due to reduced control delays are
left open as further topics of upcoming research. Another important question for application is
whether “overload-information” (i.e.
spectrum > 0.8 Hz) leads per se to
a longer control delay due to
the additional cognitive load and,
consequently, to reduced tracking
performance; if so, the information
presented to the operator should
be restricted to the useful frequency range by an appropriate
filtering.
Adaptive Interference Cancelation in Abdominal Signals for
Fetal Monitoring
Project partner: Universitatea Politehnica din Buburești, Romania
Bogdan Hurezeanu, Dragoș Țarălungă, Mihaela Ungureanu,
Werner Wolf
Biosignals mostly show large disturbances by multiple other physiological signals as well as by induced components from the environment like the power line interference. Therefore, removal of disturbances from the signal of interest
represents a classical issue in
biosignal processing like it does in
communication engineering and in
measurement and control engineering. This project specifically
focuses on the extraction of the
fetal electrocardiogram (fECG)
from the maternal abdominal signals for fetal health monitoring. In
particular, complex methods like
Independent Component Analysis
(ICA) and Periodic Component
Analysis (πCA) are considered.
Keywords: Interference cancelation, fetal monitoring, abdominal signals, biosignal processing
Fetal monitoring during pregnancy
is an important measure for the
fetal well-being. Fetal monitoring
methods have been improved during the last years, by using different
solutions to obtain biological signals that lead to fetal information.
The abdominal signal (ADS)
which is obtained by placing electrodes on the maternal abdomen
represents an alternative to the
actual clinical methods like cardiotocography (ultrasonic Doppler
principle) used for fetal monitoring.
The ADS contains several signal
components, among them the fetal
electrocardiogram (fECG). The
advantages of abdominal fECG
over the methods used nowadays
in hospitals are: i) it is noninvasive;
ii) it offers both the fetal heart rate
Figure 1: Single channel abdominal
signal recording from a pregnant
woman. Examples of the fetal heart
beats are marked by the f arrows, the
mother’s heart beat by m arrows.
(fHR) and the morphology of the
fECG signal; iii) it can be used for
long term monitoring; iv) it offers,
besides the fECG signal, the uterine contractions, the electrohisterogram signal (EHG), and the breathing rhythm.
The fHR and the fECG morphology analysis are two of the
most important tools used nowadays in clinical investigations, to
examine the health state of the
fetus during pregnancy. The fHR is
the mostly used parameter in fetal
monitoring, since 1818. While a
normal fHR shows a predictive
value of almost 99% for the fetal
well-being, an abnormal fHR, however, has a predictive value of only
50%. Hence, it provides relatively
poor specificity in detecting the
fetal distress. Additional information about the fetal well-being can
be obtained by analyzing the ECG
morphology, which was recently
introduced in clinical practice for
fetal monitoring. In particular, the
ST waveform analysis of the fECG
leads to the reduction in the number of operative vaginal deliveries,
smaller rate of metabolic acidosis
at birth, less blood samples performed during labor and fetal morbidity reduction.
The fHR is derived from the
fECG which is also not directly
accessible, thus is has to extracted
from the recorded ADS of the
mother. The fECG component of
the ADS, however, is very weak
(Figure 1) due to the attenuation
caused by the propagation through
multiple biological layers. Moreover, the fECG is corrupted by
strong interferences such as, e.g.,
the electrocardiogram of the
mother (mECG), electrode artefacts due to breathing movements,
uterine contractions, power line
interference (PLI), and the electromyogram (EMG) due to abdominal
muscle contractions.
In addition, the quality of the
fECG extraction is strongly de-
pendent on the configuration of the
electrodes. Thus, the signal-tonoise-ratio regarding the fECG/
mECG signals can be much improved just by optimally placing the
electrodes and fusing their information. However, there are no standards or guidelines available in
literature that discuss the best way
in which the electrodes should be
positioned (Figure 2) or which type
of recordings should be used
(bipolar or unipolar). Also, several
fECG extraction algorithm were
proposed, but none does include a
priori information from the electrode configuration geometry.
In this research project, performed together with the Politechnic University of Bucharest, theoretical considerations about propagation of the fECG within the tissue
volume are performed to establish
a tissue transfer function which can
be used as a priori information
when fusing the signals of the
different recording channels by
algorithms like the Independent
Component analysis. For suppression of the main disturbing component, the PLI, different algorithms
like the Event Synchronous Canceller (ESC) and the Periodic Component Analysis are successfully
investigated.
Figure 2: Laplacian electrode configuration which allows shaping of
the sensitivity characteristics on the
fetal heart. Also, the information
from the electrode configuration
geometry can be used in data fusion.
47
Human-Machine-Interaction: the Human Operator Behavior in
a Control Loop with
Manual Tracking of Continuous Random Signals
Werner Wolf, Hans Gerisch, Gerhard Staude
A basic concept in communication
technology is to describe a system
as black box by a given inputoutput-relationship. This concept
can also be applied to a human
operator being an element of a
cascaded human-machine-controlsystem (e.g., car driving). Under
the viewpoint to design optimal
systems with both human and machine integrated, the knowledge of
the human operator behavior given
by an abstract model is required in
order to adapt the technical components accordingly. Analysis of the
human operator behavior in a
tracking task is investigated using
either a hand-held joystick or a
steering wheel of a car cockpit.
Results of these interdisciplinary
investigations clearly indicate that
the transfer function of humans
declines above 0.5 Hz and tends to
zero around 1.0 Hz.
Keywords: Tracking performance, human-machine-interaction,
human operator.
Mostly for legal reasons, the human operator will not be eliminated
from a control loop, even if equivalent technical solutions are available (e.g., auto-piloting in airplanes); usually, emergency situations are the crucial points. Thus,
the human operator remains an
integral component of the overall
control-system, and, consequently,
the human-machine-interface design represents a key-factor for
human-machine-cooperation. It is
not surprising that human performance in executing control tasks
within control-systems is an intensively investigated topic. It was
mainly studied in tracking of a visual target with a hand operated
cursor as well as in smooth pursuit
eye movements when the gaze
follows a moving target. In these
cases, tracking is basically determined by the collaboration between
the sensory (visual) perception of
the target and the motor realization
of the reaction. In case of periodic
(repetitive) target movements, subjects also (unconsciously) exploit
the possibility to predict the target
movement using an internal expectancy model of the target position;
this was investigated using smooth
Figure 1: On top, details of the setup are shown: the left panel shows the
tracking stimulus arrangement, on the right the bimanual control of the steering wheel is depicted. Below, an example of the pseudo noise deflection
signal (bandwidth 0.4 Hz) is depicted, on the right, deflection (red line) and
the counteracting steering (blue line) signals are displayed on a magnified
abscissa.
48
pursuit eye movements, but was
rarely analyzed in manual tracking.
In this research project, the
experimental setup realizes the
tracking task by displaying a vertically orientated line (laser source)
on a screen, where a dark vertical
bar indicates the zero position. The
laser is fixed to the shaft of a servomotor allowing the line being
displaced horizontally, controlled
by a deflection signal with a bandwidth up to 5 Hz. The operator’s
task is to keep the line in the zero
position by counteracting movements of the steering wheel and
the joystick, respectively. Fig.1
depicts the screen situation on top
of the left with showing below the
pseudo noise deflection signal. In
the display on the lower right, the
control performance can be estimated by comparing the deflection
signal (red line) with the counteracting steering signal (blue line,
sign is inverted for better comparison). (Note the different time
scales in both plots.)
Basically, control performance
of a human operator is usually
evaluated with the control-error und
the control-delay. Large values of
both factors signal system performance limits; interestingly, an increase in the control-delay implicitly causes an increase of the control-error average in most conditions, too. In order to determine the
limits of the operator performance,
the bandwidth of the pseudo noise
signal is varied between 0.2 Hz
and 1.2 Hz. Results show that the
tracking performance declines
above 0.5 Hz and, finally, tends to
zero around 1.0 Hz.
Future research will include eye
movement recording in order to
check whether their occurrence
influences the tracking performance due to the parallel execution
of two motor tasks (i.e. hand and
eye). As well, additional eye blink
and electrocardiogram registration
will allow to assess stress aspects.
Motor Control in Humans: Motor Coordination in Multitasking
Werner Wolf, Gerhard Staude, Archil Kezeli1, Mihai Tarata2
Motor coordination is the most important process of a moving subject equipped with multiple joints
and limbs, thus basic research in
this field shows a long tradition but
is enforced by the advances in
robotics - autonomic robots must
find their way like an “autonomous”
human. In particular, the human
behavior is multidimensional (e.g.
talking during walking, pedal activation during steering in driving,
cogitating about plans during listening to music, etc), thus the brain
information processing which also
controls the motor behavior must
either show a parallel structure, or,
in case of a single processing path,
sequential concepts like timesharing. This general issue is interdisciplinary focused to human motor multitasking (i.e. performing
several actions at the same time) in
healthy people and patients with
central brain disorders. The aim of
this research is to develop an abstract model for the human motor
behavior which describes the inputoutput-relationship for the human
as an operator.
Keywords: Motor Control, Multitasking, Biosignal Processing, Human-Machine-Interface, brain disorders
A fascinating example of multitasking is the one-man-band - this
musical tradition demonstrates the
amazing capability of humans to
execute several parallel actions
with reliable spatio-temporal accuracy, which requires a high degree
motor coordination between different effectors. The coordinative
process is so naturally governed by
the central nervous system that
many of our daily multi-tasking
activities seem to be effortless and
easy. However, while musicians
are trained to perform more than
one task simultaneously, normal
individuals dealing with some dualor multi-tasking are usually troubled; e.g., bimanual interference is
found when two manual tasks are
conducted concurrently. Dual-task
costs (i.e., decreased performance
in comparison to isolated execution
of the tasks) were found not only in
bimanual but also in other dualtask combinations. Favoring a serial organization of sensorimotor
transformation stages (perception,
cognition and action) within a single channel, some researchers
attributed dual-task costs to a central bottleneck at the responseselection stage, which is assumed
to be generic, whereas others addressed the limitations of strategic
allocation of the central resources.
Single-task and dual-task tapping is employed as experimental
technique (Fig.1). The paradigm
used focuses on the coordination
of a periodic motor activity (like
walking) with randomly interspersed discrete actions (like
pressing a button in response to a
stimulus). These two quite distinct
motor actions let expect to be independently executed but in fact they
show interactions in specific situations (see PhD thesis Cong Khac
Dung).
Progress with respect of the
last activity report concerns both
the extension of the experimental
setup to include foot tapping as
well as different kinds of sensory
stimulations (3d-sound, colored
patches, etc) and the improvement
of the evaluation scripts (written in
Matlab), thus more detailed
analyses can be started now.
This research started as a project of the DFG Excellence Cluster
“Cognition for Technical Systems”
at the Technical University Munich,
addressing the problem of manmachine-cooperation. After closure
of this funding resource, the project
is continued as basic research in
biomedical information processing
and extended to include Prof.
Kezeli (schizophrenia, depression)
and Prof. Tarata (central motor
disorders) in order to integrate clinical aspects. Therefore, duplicates
of the setup are now available at
the cooperation partners in Georgia
and Romania.
1
Institute of Cognitive Neurosciencies, Agricultural University of
Georgia, Tbilisi
2
Department of Medical Informatics and Biostatistics, University
of Medicine and Pharmacy,
Craiova, Romania
Fig. 1 Hand-foot-tapping setup for investigations in motor coordination. Also,
voluntary saccadic eye movements are included as motor responses.
49
6.1 Journal Papers
Inan, B.; Spinnler, B.; Ferreira, F.; van den Borne, D.; Lobato, A.;
Adhikari, S.; Sleiffer, V.A.J.M.; Kuschnerov, M.; Hanik, N.; Jansen, S.L.:
DSP complexity of mode-division multiplexed receivers. Optics Express,
Vol.20, No.10, pp. 10859-10869, May 7, 2012.
6.1
Journal Papers
6.2
Conference Papers
6.3
Presentations
Lobato, A.; Ferreira, F.; Kuschnerov, M.; van den Borne, D.;
Jansen, S.L.; Napoli, A.; Spinnler, B.; Lankl, B.: Impact of Mode
Coupling on the Mode-Dependent Loss Tolerance in Few-Mode Fiber
Transmission. Optics Express, Vol. 20, No.28, pp. 29776-29783,
December 31, 2012.
6.4
Ph.D. Thesis
6.5
Patent Applications
Hauske, F. N.; Qi, J.; Zhao, Y.; Xie, C.; Stojanovic, N.; Pflüger, D.;
Bauch, G.: On the Mitigation of the Differential Decoding Penalty in
100G PDM-QPSK Digital Coherent Receivers for Multirate WDM
Transmission. IEEE Photonics Technology Letters, Vol.24, No.6,
pp. 428-430, March, 2012.
Wu, Z.; Schmidt, D.; Lankl, B.: Modulation-format-transparent polarization
tracking using a neural network. IEEE Photonics Technology Letters,
Vol.25, No.7, pp. 671-674, April, 2013.
Lobato, A.; Ferreira, F.; Inan, B.;
Napoli, A.; Spinnler, B.; Lankl, B.:
in Few-Mode Fiber Transmission
IEEE Photonics Technology Letters,
June 15, 2013.
Adhikari, S.; Kuschnerov, M.;
Maximum-Likelihood Detection
With Mode-Dependent Loss.
Vol.25, No.12, pp. 1095-1098,
Ferreira, F.; Fonseca, D.; Lobato, A.; Inan, B.; Silva, H.: Reach
Improvement of Mode Division Multiplexed Systems Using Fiber Splices.
IEEE Photonics Technology Letters, Vol.25, No.12, pp. 1091-1094,
June 15, 2013.
Gerisch, H.; Staude, G.; Wolf, W.: A Three-Component Model of the
Control Error in Manual Tracking of Continous Random Signals. The
Journal of the Human Factors and Ergonomics Soctiey, Vol.55, No.5,
pp. 985-1000, October, 2013.
Tarata, M.; Wolf, W.; Georgescu, D.; Alexandru, D.; Serbanescu, M.:
Comparison of SEMG Derived Parameters and Blood Oxygen Saturation
in Monitoring Neuromuscular Fatigue in Humans. International Journal
of Monitoring and Surveillance Technologies Research, Vol.1, No.4,
pp. 9-19, October-December, 2013
51
Leoni, P.; Calabrò, S.; Lankl, B.: Constellation Expansion for 100G
Transmission. IEEE Photonics Technology Letters (PTL), Vol.25, No.19,
pp. 1904-1907, October 1, 2013.
Chen, H.; Sleiffer, V.A.J.M.; Huijskens, F.M.; van Uden, R.G.H.;
Okonkwo, C.M.; Leoni, P.; Kuschnerov, M.; Grüner-Nielsen, L.; Sun, Y.;
de Waardt, H.; Koonen, A.M.J.: Employing prism-based 3-spot mode
couplers for high capacity MDM/WDM transmission. IEEE Photonics
Technology Letters (PTL), Vol.25, No.24, pp. 2474-2477, December 15,
2013.
Sleiffer, V.A.J.M.; Chen, H.; Jung, Y.; Leoni, P.; Kuschnerov, M.;
Simperler, A.; Fabian, H.; Schuh, H.; Kub, F.; Richardson, D.J.;
Alam, S.U.; Grüner-Nielsen, L.; Sun, Y.; Koonen, A.M.J.; de Waardt, H.:
Field demonstration of mode-division multiplexing upgrade scenarios
on commercial networks. Optics Express (OE), Vol.21, No.25,
pp. 31036-31046, December 16, 2013.
Sleiffer, V.A.J.M.; Leoni, P.; Jung, Y.; Surof, J.; Kuschnerov, M.;
Veljanovski, V.; Alam, S.U.; Richardson, D.J.; Grüner-Nielsen, L.; Sun, Y.;
Corbett, B.; Winfield, R.; Calabrò, S.; de Waardt, H.: 20 x 960-Gb/s Spacedivision-multiplexed 32QAM transmission over 60 km few-mode fiber.
Optics Express (OE), Vol.22, No.1, pp. 749-755, January 13, 2014.
Ţarălungă, D.D.; Ungureanu G.M.; Gussi, I.; Strungaru, R.; Wolf, W.:
Fetal ECG Extraction from Abdominal Signals: A Review on Suppression
of Fundamental Power Line Interference Component and Its Harmonics.
Computational and Mathematical Methods in Medicine, Vol.2014, p. 15,
February 9, 2014.
Leoni, P.; Calabrò, S.; Lankl, B.: Constellation Expansion for Differentially
Encoded 100G Transmission. IEEE Photonics Technology Letters (PTL),
Vol.26, No.11, pp. 1142-1145, June 1, 2014.
6.2 Conference Papers
Ţarălungă, D.; Strungaru, R.; Ungureanu, M.; Wolf, W.: Abdominal
signals: Different Concepts for Reliable fECG Recordings.
University Politehnica of Bucharest Scientific Bulletin, Series C,
Vol.74, No.3, 2012
Pflueger, D.; Bauch, G.; Hauske, F. N.; Zhao, Y.; Qi, J.; Xie, C.:
Analysis and Modeling of Phase Noise for Verification and Optimization of
Soft- Decision FEC. Photonische Netze - 13. ITG-Fachtagung, Leipzig,
Germany, May 7-8, 2012.
Adhikari, S.; Kuschnerov, M.; Jansen, S.L.; Lobato, A.; Gaete, O.; Inan, B.;
Rosenkranz, W.: Spectral Shaping on DFT-OFDM for Higher Transmission
Reach. Advanced Photonics Congress, paper SpTu2A.3, Colorado
Springs, USA, June 17-21, 2012.
Leoni, P.; Sleiffer, V.A.J.M.; Calabrò, S; Kuschnerov, M; Jansen, S.L.;
Spinnler, B.; Lankl, B.: On the Performance of a Soft Decision FEC
Scheme Operating in Highly Non-Linear Regime. Signal Processing in
Photonic Communications (SPPCom), paper SpTu3A.6, Colorado
Springs, USA, June 19-21, 2012.
Inan, B.; Spinnler, B.; Van den Borne, D.; Ferreira, F.; Lobato, A.; Adhikari,
S.; Sleiffer, V.; Hanik, N.; Jansen, S.: Equalizer Complexity of Mode-
52
Division Multiplexed Coherent Receivers. 14th International Conference
on Transparent Optical Networks (ICTON), Coventry, United Kingdom,
July 2-5, 2012. (invited)
Inan, B.; Jansen, S.L.; Spinnler, B.; Ferreira, F.; Van den Borne, D.;
Kuschnerov, M.; Lobato, A.: Adhikari, S.; Sleiffer, V.A.J.M.; Hanik, N.:
DSP requirements for MIMO spatial multiplexed receivers. IEEE
Photonics Society Summer Topical Meeting Series, Seattle, USA,
July 9-11, 2012.
Staude, G.: Patient Monitoring: Definition, Trends, Visions.
Biomedizinische Technik Supplement 1, Jena, Deutschland, Vol.57,
p. 426, September 16-19, 2012.*
Lobato, A.; Ferreira, F.; Kuschnerov, M.; van den Borne, D.;
Jansen, S.L.; Spinnler, B.; Lankl, B.: Impact of Mode Coupling on the
Mode-Dependent Loss Tolerance in Few-Mode Fiber Transmission.
38th European Conference on Optical Communications (ECOC)
Proceedings, Amsterdam, The Netherlands, September 16-20, 2012.
Schmidt, D.; Lankl, B.; Fischer, J.K.; Hilt, J.; Schubert, C.: Real-Time
Implementation of a Parallelized Feedforward Timing Recovery Scheme
for Receivers in Optical Access Networks. 38th European Conference on
Optical Communications (ECOC) Proceedings, Amsterdam, The
Netherlands, September 16-20, 2012.
Dantona, V.; Delamotte, T.; Bauch, G.; Lankl, B.: Impact of Nonlinear
Power Amplifiers on the Performance of Precoded MIMO Satellite
Systems. IEEE First AESS European Conference on Satellite
Telecommunications (ESTEL), Rome, Italy, October 2-5, 2012.
Delamotte, T.; Dantona, V.; Bauch, G.; Lankl, B.: Power Allocation and Bit
Loading for Fixed Wireless MIMO Channels. 9th International ITG
Conference on Systems, Communication and Coding (SCC), Munich,
Germany, January 21-24, 2013.
Nebel, M.; Lankl, B.: Sensitivity of the Cross-Spectrum Method for
Measurement of Oscillator Phase Noise. 9th International ITG Conference
on Systems, Communications and Coding (SCC), Munich, Germany,
January 21-24, 2013.
Pflueger, D.; Bauch, G.; Hauske, F. N.; Zhao, Y.: Design of LDPC
Codes for Hybrid 10 Gbps/100 Gbps Optical Systems with Optional
Differential Modulation. 9th International ITG Conference on Systems,
Communications and Coding (SCC), Munich, Germany, January 21-24,
2013.
Delamotte, T.; Bauch, G.; Dantona, V.; Lankl, B.: Transmit Precoding for
MIMO-BICM-ID Satellite Systems with Nonlinear Power Amplifiers.
17th International ITG Workshop on Smart Antennas (WSA), Stuttgart,
Germany, March 13-14, 2013.
Hofmann, C.A.; Ogermann, D.; Lankl, B.: Measurement Results
for the Comparison of Multiple and Single Polarized MIMO Channels
in LOS, NLOS, Indoor and Outdoor Scenarios. 17th International
ITG Workshop on Smart Antennas (WSA), Stuttgart, Germany,
March 13-14, 2013.
Ivrlač, M.T.; Lehmeyer, B.; Nossek, J.A.; Hofmann, C.A.; Lankl, B.:
Estimation of Noise Parameters in Multi-Antenna Receivers
53
using Digitized Signal Samples. 17th International ITG Workshop on
Smart Antennas (WSA), Stuttgart, Germany, March 13-14, 2013.
Leoni, P.; Sleiffer, V.A.J.M.; Calabrò, S.; Veljanovski, V.; Kuschnerov, M.;
Jansen, S.; Lankl, B.: Impact of Interleaving on SD-FEC
Operating in Highly Non-Linear XPM-Limited Regime. Optical Fiber
Communication Conference and Exposition (OFC), Anaheim, California,
USA, March 17-21, 2013.
Sleiffer, V.A.J.M.; Jung, Y.; Leoni, P.; Kuschnerov, M.; Wheeler, N.;
Baddela, N.; van Uden, R.; Okonkwo, C.; Hayes, J.; Wooler, J.;
Fokoua, E.; Slavik, R.; Poletti, F.; Petrovich, M.; Veljanovski, V.; Alam, S.;
Richardson, D.; de Waardt, H.: 30.7 Tb/s (96x320 Gb/s) DP-32QAM
transmission over 19-cell Photonic Band Gap Fiber. Optical Fiber
Communication Conference and Exposition (OFC), Anaheim, California,
USA, March 17-21, 2013.
Lobato, A.; Ferreira, F.; Rabe, J.; Inan, B.; Adhikari, S.;
Kuschnerov, M.; Napoli, A.; Spinnler, B.; Lankl, B.: On the
Mode-Dependent Loss Compensation for Mode-Division Multiplexed
Systems. 15th International Conference on Transparent Optical
Networks (ICTON) Proceedings, Cartagena, Spain, June 23-27, 2013.
(invited)
Nebel, M.; Lankl, B.: A new Way of Decomposition of Tangential and
Orbital Noise Into Phase Noise and Amplitude Noise Shown with a Simple
2-D Oscillator. 22th International Conference on Noise and Fluctuations
(ICNF), Montpellier, France, June 24-28, 2013.
Sleiffer, V.A.J.M.; Jung, Y.; Leoni, P.; Kuschnerov, M.; van Uden, R.;
Veljanovski, V.; Grüner-Nielsen, L.; Sun, Y.; Richardson, D.; Alam, S.;
Poletti, F.; Corbett, B.; Winfield, R.; de Waardt, H.: High capacity multimode transmission systems using higher-order modulation formats. 18th
Opto-Electronics and Communications Conference (OECC), Kyoto, Japan,
June 30 - July 4, 2013. (invited)
Ţarălungă, D.D.; Ungureanu, G.M.; Hurezeanu, B.; Gussi, I., Strungaru,
R.; Wolf, W.: Fetal Electrocardiogram Enhancement in Abdominal
Recordings: Recording Setup Analysis. 35th Annual International
Conference of the IEEE Engineering in Medicine and Biology Society
(IEMBS), Osaka, Japan, July 3-7, 2013.
Ungureanu G.M., Ţarălungă, D.D.; Gussi, I.; Wolf, W.; Piper, D.;
Strungaru, R.: Monitoring the Fetal Heart Rate Variations by Means of
Time-Variant Multivariate Analysis. 35th Annual International Conference
of the IEEE Engineering in Medicine and Biology Society (IEMBS), Osaka,
Japan, July 3-7, 2013.
Sleiffer, V.A.J.M.; Jung, Y.; Leoni, P.; Kuschnerov, M.; Veljanovski, V.;
Wheeler, N.; Baddela, N.; Hayes, J.; Wooler, J.; Numkam, E.; Slavik, R.;
Poletti, F.; Petrovich, M.; Alam, S.; Richardson, D.; de Waardt, H.:
A First Glance at Coherent Optical Transmission using Photonic
Bandgap Fiber as a Transmission Medium. IEEE Photonics Society
Summer Topicals Meeting (SUM), Waikoloa, Hawaii, USA,
July 8-10, 2013. (invited)
Schmidt, D.; Wu, Z.; Lankl, B.: Clock Recovery by Fractionally Spaced
Equalizers for Parallelized Receivers in Optical Networks. Signal
Processing in Photonic Communications (SPPCom), Rio Grande, Puerto
Rico, July 14-17, 2013.
54
Lobato, A.; Ferreira, F.; Rabe, J.; Inan, B.; Adhikari, S.; Kuschnerov, M.;
Napoli, A.; Spinnler, B.; Lankl, B.: Mode-Dependent Loss Mitigation for
Mode-division Multiplexed Systems. Advanced Photonics Congress,
Rio Grande, Puerto Rico, July 14-19, 2013. (invited)
Leoni, P.; Sleiffer, V.A.J.M.; Calabro, S.; Veljanovski, V.; Kuschnerov, M.;
Lankl, B.: Pre FEC Error Burstiness for 100G Systems Operating in
Heavily XPM-Limited Regime. Signal Processing in Photonics
Communications (SPPCom), Rio Grande, Puerto Rico, July 14-17, 2013.
Pflueger, D.; Bauch, G.; Zhao, Y.; Hauske, F. N.: Conditions on Degree
Distributions to Compensate Differential Penalty by LDPC Turbo
Decoding. IEEE 78th Vehicular Technology Conference (VTC Fall),
Las Vegas, USA, September 2-5, 2013.
Ludwig, S.; Börner, J.; Lankl, B.: Orthogonal Receive Symbols at the
Receiver for Fast-Fading Rayleigh Channels. AFRICON, Le Meridien - Ile
Maurice, Pointe Aux Piments , Mauritius, September 9-12, 2013.
Leoni, P.; Sleiffer, V.A.J.M.; Calabrò, S.; Lankl, B.: Constellation
Expansion and Iterative Demapping and Decoding for 100G Systems.
39th European Conference and Exhibition on Optical Communication
(ECOC), London, England, September 22-26, 2013.
Sleiffer, V.A.J.M.; Leoni, P.; Jung, Y.; Surof, J.; Kuschnerov, M.;
Veljanovski, V.; Richardson, D.; Alam, S.; Grüner-Nielsen, L.; Sun, Y.;
Corbett, B.; Winfield, R.; Calabrò, S.; Sommerkorn-Krombholz, B.;
von Kirchbauer, H.; de Waardt, H.: 20 x 960 Gb/s MDM-DP-32QAM
transmission over 60km FMF with inline MM-EDFA. 39th European
Conference and Exhibition on Optical Communication (ECOC), London,
England, September 22-26, 2013.
Pflüger, D.; Zhao, Y.; Qi, J.; Hauske, F. N.; Bauch, G.: Soft-Information
Quality Analysis for Optimum Soft-Decision Forward Error Correction.
IEEE Photonics 2012 Conference (IPC12), Burlingame, USA,
September 23-27, 2012.
Lobato, A.; Ferreira, F.; Rabe, J.; Kuschnerov, M.; Spinnler, B.; Lankl, B.:
Mode Scramblers and Reduced-Search Maximum-likelihood Detection for
Mode-Dependent-Loss-Impaired Transmission. European Conference on
Optical Communications (ECOC) Proceedings, London, England,
September 22-26, 2013.
Wolf, W.: Tapping Can Reveal Motor Coordination Problems.
Tbilisi International Conference Merging Neuroscience and Medicine:
Implications for Brain Disorders, Biomedical Series, Supplementum 39,
Tbilisi, Georgia, October 1-4, 2013
Fettweis, G.; Lankl, B.; Grass, E., Krone, S.: Maximum Spectral
Efficiency Through Parallelized Multiple-Input-Multiple-Output (MIMO)
Transmission Using High-Resolution 3D Antenna Topologies
(maximumMIMO). European Microwave Conference (EuMC & EuMIC),
Workshop 19: Ultra High Speed Wireless Communication: Approaches
and Ideas to Achieve Wireless 100Gb/s Communication, Nuremberg,
Germany, October 6-11, 2013.
Tax, N.; Lankl, B.: Fixed Effort Sphere Decoder for MIMO
OFDM Systems. International Conference on Wireless Communications
and Signal Processing (WCSP), Hangzhou, China, October 24-26,
2013.
55
Knopp, A.; Schwarz, R.T.; Lankl, B.: Secure MIMO SATCOM
Transmission, IEEE Military Communications Conference (MILCOM),
pp. 284-288, San Diego, California, USA, November 18-20,
2013.
Lewandowsky, J.; Ludwig, S.; Lankl, B.: Detection by Inherent Channel
Estimation in Rapidly Fading Channels. 7th International Conference on
Signal Processing and Communication Systems (ICSPCS), Gold Coast,
Australia, December 16-18, 2013.
Leoni, P.; Sleiffer, V.A.J.M.; Calabrò, S.; Lankl, B.: Constellation
Expansion and Multi-Symbol Detection for Differentially Encoded 100G
Systems. Optical Fiber Communication Conference and Exposition (OFC),
San Francisco, California, USA, March 9-13, 2014.
Sleiffer, V.A.J.M.; Leoni, P.; Jung, Y.; Chen, H.; Kuschnerov, M.; Alam,
S.U.; Petrovich, M.; Poletti, F.; Wheeler, N.; Baddela, N.; Hayes, J.;
Numkam, E.; Richardson, D.J.; Grüner-Nielsen, L.; Sun, Y.; de Waardt, H.:
Ultra-high capacity transmission with few-mode silica and hollow-core
photonic bandgap fibers. Optical Fiber Communication Conference and
Exposition (OFC), San Francisco, California, USA, March 9-13, 2014.
(invited)
Lehmeyer, B.; Ivrlač, M.T.; Mezghani, A.; Nossek, J.A.; Lankl, B.:
On Matching Strategies for Wireless Receivers. 18th International
ITG Workshop on Smart Antennas (WSA), Erlangen, Germany,
March 12-13, 2014.
Fischer, J.K.; Elschner, R.; Frey, F.; Hilt, J.; Kottke, C.; Schubert, C.;
Wu, Z.; Schmidt, D.; Lankl, B.: Digital signal processing for coherent
UDWDM passive optical networks. 15. ITG-Fachtagung Photonische
Netze, Leipzig, Germany, May 5-6, 2014.
Wu, Z.; Lankl, B.: Polar Codes for Low-Complexity Forward Error
Correction in Optical Access Networks. 15. ITG-Fachtagung Photonische
Netze, Leipzig, Germany, May 5-6, 2014.
6.6 Presentations
Pflüger, Doris: Design of LDPC Codes with a Turbo Loop to the
Differential Modulation, Université de Neuchâtel, Neuchâtel, Swizerland,
March 4, 2013.
Pflüger, Doris: Design of LDPC Codes for Hybrid 10Gbps/100Gbps Optical
Systems with Optional Differential Modulation, Hamburg-Harburg
University of Technology, Hamburg, Germany, January 9, 2014.
Pflüger, Doris: Conditions on Degree Distributions to Compensate
Dierential Penalty by LDPC Turbo Decoding, Alcatel-Lucent, Stuttgart,
Germany, February 17, 2014.
6.7 Ph.D. Theses
Carrier Synchronization in High Bit-Rate Optical Transmission Systems
(K. Piyawanno, 2012), Verlag Dr. Köster Berlin, ISBN 978-3-89-574848-6
The Importance of Digital Signal Processing in High Speed Optical
Receivers: Equalization, Impairment Compensation and Performance
56
Monitoring (F. Hauske, 2013), Verlag Dr. Köster Berlin, 978-3-89-574827-1
Basic Timing Concepts for the Execution of Multiple Motor Tasks:
Coordination of Periodic Tapping with Discrete Tasks (D. Cong Khac,
2012)
Periphere Magnetstimulation zur Frührehabilitation zentral-bedingter
Lähmungen von Arm und Hand in den ersten Wochen nach Schlaganfall
(L. Premoselli, 2012)
6.8 Patent Applications
Jan Christopher Lewandowsky, Stephan Ludwig, Berthold Lankl,
Martin Thienel:
Datenübertragungsverfahren für Kanäle mit schnellveränderlichen
Übertragungseigenschaften. DE-Patentanmeldung, Juli 2013
57
Communications and Coding - SCC2013
Communications and Coding - SCC2013
The SCC, formerly known as the "International Conference on Source and
Channel Coding" takes place every two years and is organized by the
Technical Committee ITG "Information and Systems Theory". In the main
auditorium of the University met for four days more than 150 scientists and
industry representatives and high profile guest speakers from the fields of
"information theory", "communication" and "navigation systems". The conference was organized by Prof. Dr.-Ing. Gerhard Bauch (Technical University Hamburg-Harburg) and Prof. Dr.-Ing. Berthold Lankl (Institute for Information Technology) and Prof. Dr. sc. Christoph Günther (German Center
for Aviation DLR Oberpfaffenhofen / Technical University of Munich) and
Prof. Dr.-Ing. hab. Volker Kühn (University of Rostock) organized.
♦
9th International ITG
Conference on Systems,
Communications and
Coding - SCC2013
♦
Mädchen machen Technik
♦
Institute Excursion
♦
Christmas Parties
Central themes - Wireless Communication and Network Coding
The conference started with three tutorials from the fields Optimization for
Communications, Principles of compressed sensing and New Challenges
for Engineers in Advanced Optical Communication Networks. The second
day was dedicated to the field of wireless communication with the guest
speakers Takehiro Nakamura ( NTT DOCOMO, Japan) and Dr. Erik
59
Dahlman (Ericsson, Sweden). In the afternoon, said Prof. Hans-Andrea
Loeliger (Federal Institute of Technology Zurich, Switzerland) about the
following channel coding and information theory. The focus of the third day
were the points network coding and MIMO systems (Multiple Input, Multiple Output). A field trip to the DLR was able to visit the German Space
Operations Center and the Galileo Control Center. Then guides were presented by the laboratories of the Institute of Communications and Navigation, the research focus of the Institute for.
Recent research on the topic navigation
The last day was devoted to optical communications. Dr.-Ing. Henning
Bülow (Alcatel -Lucent Bell Labs , Germany) and Dr. Peter J. Winzer
(Alcatel -Lucent Bell Labs , USA) illuminated the capacity limits of optical
transmission and MIMO in optical systems. Prof. Dr. Günter W. Hein
(European Space Agency, The Netherlands) and Prof. Dr. Henk Wymeersch (Chalmers University of Technology, Sweden) presented the
topic navigation present their research results. The lecture by
Prof. Rüdiger Urbanke (Ecole Polytechnique Federale de Lausanne, Switzerland ) on the latest advances in channel coding ended the conference.
The accompanying poster exhibition in the foyer of the auditorium was well
accepted among scientists, there developed throughout the meeting numerous technical discussions. The next International ITG Conference on
Systems, Communications and Coding will be held in 2015 in Hamburg.
60
Mädchen machen Technik
Biosignals - Windows to Our Body
Gerhard Staude
Can we make our thoughts visible?
Can we hear our muscles working?
Questions like these were addressed by teenage girls between 12 and 14 years who participated in the BIOSIGNALS project during summer holidays 2012
and 2013.
Assisted by staff members and
Ph.D. students the participants
enthusiastically mounted electrodes, turned their lunch into bioelectrical voltage generators, registered eye movements, and analyzed heart rates and reaction
times. During the three project
days the girls proactively experienced a variety of biomedical signal registration and analysis techniques which are used by physicians for clinical diagnosis and
employed by scientists for basic
research. Registration of cardiac
activity (ECG), cerebral activity
(EEG), or muscular activity (EMG)
are well-known examples.
Starting with a brief introduction
into basic biological and technical
facts, the girls conducted experiments and measurements by themselves, thus getting a tantalizing
glimpse into the fascinating field of
BIOSIGNALS project
Staff of Professur für
(Prof. Gerhard Bauch)
Direction and presentation
PD. Dr.-Ing. Gerhard Staude
Cornelia Budach (logistics)
Josef Dochtermann
(logistics, IT systems)
Wolfgang Hanzl (logistics)
Wolfgang Weber
(experimental setup, bioelectricity)
Prof. Dr.-Ing. Werner Wolf
(driving simulator)
The BIOSIGNALS project is part of
the annual Girls and Technology
summer school of the Bavarian
universities and research institutions for girls aged between 10
and 16 years. The summer school
is organized by the Girls in
Science and Technology agency,
an institution of the Women’s
representative of the Technische
Universität München.
Students and Ph.D. students:
Benjamin Fabinger, EIT09
(tutor signal registration)2012-2013
Susann Kohlmetz, EIT09
(tutor signal registration) 2012
Thomas Kürsten, EIT09
(tutor signal registration) 2013
Christian Speer, EIT09
(driving simulator) 2013
Dipl.-Sportwiss. Miriam
Ködderitzsch-Frank
(motor coordination) 2012-2013
Dipl.- Sportwiss. Florian Frank
(motor coordination) 2013
biomedical information technology.
Questions like Who is the fastest
and most accurate fighter against
her virtual opponent in the electronic fencing simulation were
examined at least as attentively
as the mathematical and technical
basics of computer tomography
and magnetic resonance imaging
technologies.
61
Institute Excursions
On our Institute Excursion in 2012
we went to hike along the Osterseen in the morning of the 24th of
July. The Osterseen are a couple
of small lakes close to munich,
south of the Starnberger See. To
the nature-sanctuary belong more
than 30 lakes. They were created
in the last glacial period. Their
name does not derive from the
Christian festival Ostern (eastern),
but from the Osern (eskers), a
long, winding ridge of stratified
sand and gravel formed by the
glacial melt water.
We met at the paking area
close to the Fohnseestüberl. This is
a Biergarten located in Iffeldorf
next to the Fohnsee, one of the
southern lakes of the Osterseen.
We started there our hike around
the Fohnsee and the Großer Ostersee. The path always led closely
along the lakeside. This allowed
splendid views on the water. Parts
of the tour crossed moorlands with
their particular landscape. We also
passed by the Blaue Gumpe. This
is a cone, where water is swelling
into the lake. As the edges are
covered with white lime and the
water has a constant temperature
the whole year, the water appears
particular blue. This is a typical
phenomenon at the Osterseen.
The weather was wonderful sunny
and warm. So we were glad about
the shady trees along the way. We
ended our hike after about 9 kilometers with a delicious lunch back
at the Fohnseestüberl. In the afternoon we relaxed at the lakeside
and enjoyed the sun. Some had
coffee and interesting conversations, while others went for a swim
in the Fohnsee or played cards.
62
On July 10, 2013 we met in good
weather at the parking lot of Hotel
Grauer Bär at Lake Kochel. The
Lake is located about 50 km south
of Munich near the Alps. The south
bank is already surrounded by
mountains, where else the flat preAlpine landscape is against the
North Shore.
We started our journey around
the lake with a walk in the direction
of the Walchensee power plant at
the southern tip of the lake. On our
way we passed a camping site,
where just two military helicopters
had landed by a large group of
soldiers. As we were to learn later,
it was paratroopers who jumped
into the Lake during the day.
After we had passed the power
plant the path led us at the foot of a
historical long wave radio station.
The narrow path to the west of lake
Kochel is dominated by the steep
shore. A few vantage points offered
nice change.
Around lunch time we reached
Schlehdorf in the northwest of the
lake, where we had lunch in the
Klosterschänke after a short visit to
the monastery Schlehdorf.
Later in the afternoon we continued our journey around the lake
by ferry. About Kochel we reached
back to our starting point. A nice
pastime on the ferry was to observe the parachutists and listen to
the comments the other passengers marveled about them.
After our return the official part
was over. One group rounded off
the trip with ice cream, coffee and
cake at the shore. The other visited
the Lainbachfälle, a series of impressive waterfalls of a stream
which flows into the Lake. Both
were a fitting conclusion for a nice
excursion.
63
Christmas Parties
In 2012, our Christmas party took
place on December 11th. The
first part consisted in a Bavarian
lunch in a restaurant located in
Neubiberg. Unfortunately, Prof.
Lankl couldn´t join us for long during this lunch due to his teaching
activities. Christmas parties are
surely interesting but teaching engineering is even more.
After this lunch, we had the
occasion to play “Kegeln” in a room
just under the restaurant. Since he
had finished his lecture, Prof. Lankl
took part in this activity and he
kindly invited all the institute.
“Kegeln” is a game quite similar to
bowling whose principle is to use a
ball to knock over as much pins as
you can. The difference between
the two are the number of pins (in
Kegeln is 9 and in bowling 10); the
ball (heavier and has 3 holes in
bowling, while in Kegeln the ball
has no holes); and, the way the
pins are organized at the end of the
track (in bowling a triangle and in
Kegeln a rhombus). We can mention this exploit of Mr. Hanzl who
launched his ball with so much
strength that it didn´t knock over
any pin but rather ended up in a
hole on the side of the track normally designed to get the balls
back. But don´t worry ! Nothing
was broken!
Later in the afternoon, we came
back in the restaurant and took the
time to enjoy the taste of a Helles
or a Weißbier together with traditional Christmas pastries. We spent
some time there talking about life
at the university, the achievable
peak data rates in the Long Term
Evolution standard or professional
plans after the PhD.
64
On 17th December of 2013, the
institute staff chose to honor one of
Germany’s most famous and loved
humorists, Loriot (a.k.a. Vicco von
Bülow), by visiting the exhibition
“Loriot. Spätlese” which was
hosted in the Literaturhaus
München (Salvatorplatz) from
20.09.2013 to 12.01.2014. This
exhibition featured a great deal of
previously unpublished material
that was posthumously made available by the artist’s family. Having
died of old age in 2011, the 12th
November 2013 would have been
Loriot’s 90th birthday.
After having the honor of a
guided tour through the exhibition
before the regular opening hours,
the staff stopped off at the
“Nürnberger Bratwurst Glöckl am
Dom” directly in the vicinity of the
Frauenkirche to enjoy a hearty and
equally tradition-steeped lunch: the
“Bratwurst Glöckl” inn can be
traced back to documents as early
as 1390, thus preceding the
Frauenkirche. Staff members enjoyed a rustic meal of Nuremberger
bratwurst served on pewter plates
and accompanied by delicious side
dishes such as potato salad, sauerkraut and grated horse radish. Ample opportunity for chatting among
each other was observed until a
smaller group returned back to the
institute’s “Blaues Eck” for a quiet
conclusion of the day with snacks
and sweets. On this occasion, especially the senior staff members
reminisced about the good old
early days of technology, where
writing a computer program meant
to punch holes into a strip of paper,
taking pictures required manually
spooling photographic film, and
radios employed “magic eye” tubes
for signal strength indication.
65
Professur für Informationsverarbeitung
N.N.
Universität der Bundeswehr München
D-85577 Neubiberg
Tel.: (+49)89 6004 3630
Tel.: (+49)89 6004 3607
Fax: (+49)89 6004 3641
Fax: (+49)89 6004 3603
GPS: 48.07986°N, 11.63764°E

Activity Report - Universität der Bundeswehr München

Transcription

Similar documents

Kaleidoscope Optical Illusions

Provider network: there`s always a provider in sight

First 100 days of the new OMB Chairman

Workshop on Case Method of Teaching at ICFAI University

Call for Papers

OptiDriver™ High-Density Metro Optical Transport Platform

Call for Presentations

STORCZYK 2010 Digital Communication System

08 - Rohrbasser - Electrophorese capillaire_projet PHARMELP

100 Mb/s Ethernet Transmission Over 275 m of Large Core