Smart Notching – New concepts for EMC coordination

Smart Notching
– New concepts for EMC coordination
Andreas Schwager, Sony Deutschland GmbH,
European Technology Center (EuTEC), Stuttgart, Germany,
[email protected]
Prof. Dr. Holger Hirsch, Universität Duisburg-Essen,
Energietransport und –Speicherung, Duisburg, Germany,
[email protected]
European Technology Center
Andreas Schwager
(1)
Outline
• Overview of today‘s EMI coordination
• Adaptive EMI mitigation techniques
– Satellite Communications
– Overlay OFDM
– Dynamic Notching for PLT
•
•
•
•
Motivation of PLT
Interference problems and solutions
Implementation of a Prototype system
ETSI PLT plugtest with EBU
– Results & EBU Statement
• Conclusions
European Technology Center
Andreas Schwager
(2)
EMC-Coordination
Coordination of emission and immunity requirements
to guarantee the EMC of an electrical device
real conditions
ideal conditions
variance due to manufacturing
disturbances not considered
level
level
immunity level
immunity level
immunity limit
compatibility level
compatibility level
emission limit
emission level
Frequ
emission level
cum. probability
EMC coordination: risk management !
European Technology Center
Andreas Schwager
(3)
Adaptive EMI mitigation techniques
are in use for lots of applications
– Satellite Communications
– Overlay OFDM
– Dynamic Notching for PLT
European Technology Center
Andreas Schwager
(4)
Frequency Management for Mobile Satellites
From:
Rickerson, D.; Rhoads,
“Symphony or calliope-frequency
management with mobile satellite
services” M.;
Military Communications Conference, 1996. MILCOM '96, Conference Proceedings, IEEE
Volume 3, 21-24 Oct. 1996 Page(s):943 947 vol.3
European Technology Center
Andreas Schwager
(5)
Overlay OFDM systems
From:
Rakesh Rajbanshi “OFDM-Based
Cognitive Radio for DSA Networks”
September 2007, University of
Kansas
European Technology Center
Andreas Schwager
(6)
Air Traffic Control
From:
B-VHF – An Overlay system
concept for future ATC
communication in the VHF
band
M. Schnell, E. Haas;
German Aerospace Center
(DLR)
M. Sajatovic, C. Rihacek, B.
Haindl; Frequentis GmbH
23rd Digital Avionics
System Conference
(DASC); Oct. 24-28, 2004;
Salt Lake City, Utah, USA
European Technology Center
Andreas Schwager
(7)
Air Traffic Control
From:
B-VHF – An Overlay system
concept for future ATC
communication in the VHF
band
M. Schnell, E. Haas; German
Aerospace Center (DLR)
M. Sajatovic, C. Rihacek, B.
Haindl; Frequentis GmbH
23rd Digital Avionics System
Conference (DASC); Oct.
24-28, 2004; Salt Lake City,
Utah, USA
European Technology Center
Andreas Schwager
(8)
Same Concept will be used for
Powerline Communications
European Technology Center
Andreas Schwager
(9)
Heterogeneous Home Network
•
HDTV
•
PDA
•
Baby Monitor
PC
Audio System
European Technology Center
Andreas Schwager
(10)
A/V Home Server
•
Wireless solution suffers
from insufficient
coverage
PLT provides Broadband
coverage in solid-wall
households without new
wires
PLT as in-home
backbone media,
complementary to
wireless
High
comfort/convenience
factor for the user
PLT Interference problems
SW Radio Broadcast <-> In-home
• Frequency range of PLT is
identical to SW radio.
Home
Server
DSL
Router
www
• Interference avoidance
techniques, like
‘Smart Notching’ remove
interference to all receivable
radio carriers
amplitude
in-home BPL
spectrum
SW Radio
spectrum
European Technology Center
Andreas Schwager
(11)
frequency
PLT Interference problems
SW Radio Broadcast <-> In-home
• Frequency range of PLT is
identical to SW radio.
Home
Server
DSL
Router
www
• Interference avoidance
techniques, like
‘Smart Notching’ remove
interference to all receivable
radio carriers
amplitude
in-home BPL
spectrum
SW Radio
spectrum
European Technology Center
Andreas Schwager
(12)
frequency
PLT Interference problems
SW Radio Broadcast <-> In-home
Home
Server
• Video recorded in a
real building:
• AM reception
PLT Sink
• DRM Reception
• Worst case of interference:
amplitude
in-home BPL
spectrum
• PLT transmitter in vicinity of
SW-receiver
SW Radio
spectrum
European Technology Center
Andreas Schwager
(13)
frequency
Video recorded in a real building:
AM reception (Sony ICF-SW77)
European Technology Center
Andreas Schwager
(14)
Screen shot of user interface of Sony PLT system
European Technology Center
Andreas Schwager
(15)
ETSI PLT plugtest
STF 332: http://portal.etsi.org/STFs/STF_HomePages/STF332/STF332.asp
PLT Modem
European Technology Center
Andreas Schwager
(16)
Frequency hop of Skelton Radio transmission
• Skelton transmission toggled from 7225kHz to 7320kHz.
There are 2 radios tuned to each frequency.
In parallel there is PLT transmission inside the building from
Sony’s Smart Notching demonstrator:
1st Radio tunes to 7225kHz.
This frequency is notched by
PLT system.
No interference!
ps
o
t
by
s
on
o
s s
di
s
e
a
e
t
h
h
R
tc star
i
ti c
d
n
sw Hz
2
sw
n
z
Hz 0k
o
H
k
2
0
T tch
z
5k
3
Strong PLT interference
2
L
2
7
H
o
3
P
k
n
7 on
72
5
noticealbe at the 2nd radio
m
n
a
n
o g
o on
22
r
o
f
n
7
n
i
(tuned to 7320kHz).
n
e r ti
io lat
s
o
i
c
s
e
e
s
n
u
s
s
i
e ins
d
is
u
r
m
o
e
m
e
r
s
m
rf
ns
n
a
e
T
t
a
Tr
AM
In
Tr
PL
0
European Technology Center
Andreas Schwager
(17)
of
13
14
f
17
69
Time in sec
Test procedure
• A SW radio receiver did an automatic frequency scan in all
ITU-R radio bands
– Sony ICF-SW77 was used (the most sensitive, we found)
• At all broadcast services where the automatic scan stops an
SINPO assumption was done
• ITU-R Recommendation BS.1284:
"General methods for the subjective assessment of sound quality“
http://stason.org/TULARC/radio/shortwave/08-What-is-SINPO-SIO-Shortwave-radio.html
– PLT active, no notches
– PLT active, smart notching installed
– PLT off
European Technology Center
Andreas Schwager
(18)
Field tests: SINPO assumption
• 168 times SINPO assumption performed
DRM
Quality of the
Not useable
radio service:
European Technology Center
Andreas Schwager
(19)
News talker
could be
understood
Music might be
enjoyed
Good AM
quality
FM quality
(DRM only can provide
this in SWfrequencies)
European Broadcasting Union
Union Européenne de Radio-Télévision
Technical Department
Département technique
9 January 2008
EBU S/EIC1
Statement with regard to ETSI specification of PLT
"Smart Notching" system
The latest version of the Coexistence Specification (ETSI TS 102 578 v1.1.16 – 2007-11;
PowerLine Telecommunications (PLT) Coexistence between PLT Modems and Short
Wave Radio Broadcasting) services was considered by the EBU S/EIC group at its
meeting on the 28th and 29th November 2007.
Within the provisions:
the document concerns itself specifically with a system of dynamic notching (referred to as
“Smart Notching”) whereby a PLT modem omits, or ‘notches’ certain frequencies and
frequency ranges from the signal which it uses to communicate with other PLT modems.
Other aspects of PLT systems and system design outside the scope of the specification
are excluded;
-
the protection (dynamic notching) system is designed only to protect HF broadcast
transmissions services in specified bands between 2 MHz and 30 MHz;
-
the EBU S/EIC group is content that any system fully meeting the specification will
offer adequate protection to HF (Short Wave) broadcast transmissions. The EBU
S/EIC group will therefore recommend to EBU members that are also members of
ETSI that they should support the adoption of the specification within ETSI.
Further to this a representative of the EBU, Mike Hate, was present during the tests
described in document
ETSI TR 1XX W124 v2.1.x (PLT44_TD_12r1_ETSI_TR_WI24_Part2_V2_0_3.doc.
European Technology CenterThe EBU S/EIC group confirms that this document is a fair and accurate report of the tests
Andreas Schwager
carried out and
the results obtained.
(20)
Conclusions
•
•
•
There is a wide range of Applications allocating frequency spectrum
dynamically.
Online analysis allows an adaptation of the system on the current
local situation.
EMI is not guaranteed at manufacturing of the device but due the
concept of operation.
– For PLT ETSI specified a TS including verification mechanism
•
Protection of existing radio applications is guaranteed
•
Adaptive Mitigation techniques are state of the art in today’s
standards & norms:
– EN 50065-1: Signaling on low-voltage electrical installations in the
frequency range 3 kHz to 148,5 kHz
• §4 Frequency bands and classifications
NOTE: Additional provisions may apply in the event of interference to radio
communication service.
European Technology Center
Andreas Schwager
(21)