5G New Physical Layer Design and Test November, 2014 Sang-Kyo Shin
Transcription
5G New Physical Layer Design and Test November, 2014 Sang-Kyo Shin
5G New Physical Layer Design and Test November, 2014 Sang-Kyo Shin Keysight EEsof EDA Agenda – Objective – Multi-Carrier Waveform Techniques • OFDM vs. FBMC • FBMC signal processing • Reference transmitter and receiver modeling, simulation and test – MIMO and Digital Beamforming Techniques • Diversity, Spatial Multiplexing • Multi-user, Massive MIMO • Modeling and Simulation Case studies 5G & mmWave Workshop Page 2 5G Enabling Devices >> New 5G R&D Challenges Advanced signal processing New waveforms • • Legacy OFDM enhancement FBMC, GFDM, UFDM • • • Multiple MIMO modes and beamforming Network interference suppression Adaptive channel estimation / equalization Full duplex communications • • • Amplifier • • • Envelope tracking Digital predistortion Wide, multi bands Multi-antenna • • • Access • • Self interference cancellation Dual polarization antenna Real time operation Non-orthogonal multiple access Random / scheduled / hybrid • Multi-band Multiple radio access technologies • • Impedance matching Mutual coupling Multi-band, multi-RAT port sharing FD / Massive MIMO GSM/EDGE/WCDMA/HSPA/LTE WiFi/BT/WiGig/GNSS/5G • • • Traditional cellular bands <6GH WiFi, BT, GNSS bands 5G mmWave bands 5G & mmWave Workshop Page 3 What we have for early 5G research today? W1906BEL, 5G baseband exploration library • 5G candidate physical layer modeling source codes for early research customer • Committed by Keysight evolving toward world’s first 5G standard compliant library MATLAB_Script M1 {MATLAB_Script@Data Flow Models} Modeling New Physical Layer – Provide 5G candidate waveform • Multi-carrier modem Tx/Rx processing chain • FBMC,OFDM, etc… – Usable with 4G standard library Multi-Antenna Techniques – Advanced / adaptive signal processing • MIMO • Digital beamforming – Combined 2D/3D MIMO channel simulation(W1715) Algorithm Design / Verification – Real world simulation environments with polymorphic language selection • Custom C++ model builder • MATLAB® • MATLAB® Script™ 5G & mmWave Workshop Tackling Multi-Domain Issues – Integrated to advanced platform • SystemVue/ADS/EMPro/ GG • Keysight Instruments Page 4 Agenda – Objective – Multi-Carrier Waveform Techniques • OFDM vs. FBMC • FBMC signal processing • Reference transmitter and receiver modeling, simulation and test – MIMO and Digital Beamforming Techniques • Diversity, Spatial Multiplexing • Multi-user, Massive MIMO • Modeling and Simulation Case studies 5G & mmWave Workshop Page 5 Waveform Requirements Figure 1. – OFDM vs. FBMC Spectrum Using different filter overlap factor • Enable efficient multiple access • High density of users • Carrier assignment schemes in asynchronous context Figure 2. – FBMC Fragmented Spectrum • Efficient usage of the allocated spectrum • Robustness to narrow-band jammers and impulse noise Figure 3. • High performance spectrum sensing – Prototype Filter Design • Low computational complexity – Filter overlap factor K : number of multicarrier symbols which overlap in the time domain • Compatibility OFDM vs. NEW 5G & mmWave Workshop Page 6 Waveform Design Considerations for 5G Waveform Bandwidth / Frequency Advanced Multi-Carrier Waveforms1 OFDM 3GHz FBMC / OFDM / Others 10GHz Single carrier 30GHz 90GHz >> Wider BW, Higher Fc, More robustness against phase noise New RAT OFDMA/ NOMA? NOMA/ OFDMA? Note1: • • • • • Orthogonal Frequency Division Multiplexing(OFDM) Filter Bank Multicarrier(FBMC) Universal Filtered Multicarrier(UFMC) Generalized Frequency Division Multiplexing(GFDM) Biorthogonal Frequency Division Multiplexing(BFDM) 5G & mmWave Workshop Page 7 OFDM Advantage Drawback – Good spectral efficiency – Some loss of spectral efficiency due to Cyclic Prefix insertion – Resistance against multipath interference – Efficiently implemented using FFTs and IFFTs – Imperfect synchronization cause loss of orthogonality – Subcarrier nulls correspond to peaks of adjacent subcarriers for zero inter-carrierinterference – Large peak to average power ratio(PAR) leads to amplifier inefficiency – High out-of-band power – Subcarrier intermodulation must be reduced frequency f1 f2 5G & mmWave Workshop Page 8 Synthesis Filter bank Symbol de-mapping Symbol de-mapping FFT S / P P / S IFFT Sub-carrier mapping Symbol mapping Sub-carrier de-mapping OFDM baseband signal processing blocks Sub-carrier de-mapping post processing OQAM FFT Poly Phase Network S / P P / S Poly Phase Network IFFT OQAM preprocessing Sub-carrier mapping Symbol mapping OFDM vs. FBMC Analysis Filter bank FBMC baseband signal processing blocks 5G & mmWave Workshop Page 9 FBMC Signal Processing Block OQAM preprocessing 𝐶2𝑅𝑘 𝑑0, 𝑛 Synthesis Filter Bank 𝜃0, 𝑛 𝛽0, 𝑛 x x 𝛽1, 𝑛 x x . . . . . . 𝑑1, 𝑛 𝛽 0, 𝑛 𝐴0(𝑧 2 ) ↑ 𝑀/2 + 𝑧 −1 𝐴1(𝑧 2 ) 𝑰𝑭𝑭𝑻 . . . ↑ 𝑀/2 . . . ↓ 𝑀/2 x 𝜃 0, 𝑛 𝑆𝑢𝑏𝐶𝐻 Proc x x . . . 𝐴𝑀 − 1(𝑧 2 ) ↑ 𝑀/2 . . . 𝛽 1, 𝑛 ↓ 𝑀/2 𝐵 1(𝑧 2 ) . . . . . . Transform Poly phase filtering FBMC transmitter P/S Conversion 𝑭𝑭𝑻 ↓ 𝑀/2 S/P Conversion 𝐵 𝑀 − 1(𝑧 2 ) 𝑆𝑢𝑏𝐶𝐻 Proc 𝑅𝑒 x x . . . 𝛽 𝑀 − 1, 𝑛 𝜃𝑀 − 1, 𝑛 𝑆𝑢𝑏𝐶𝐻 Proc Transform x Sub channel processing 𝑅2𝐶𝑘 𝑑 1, 𝑛 𝑅𝑒 . . . x Poly phase filtering 𝑑 0, 𝑛 𝜃1, 𝑛 x 𝑧 −1 𝑑𝑀 − 1, 𝑛 Staggering 𝐵 0(𝑧 2 ) 𝑧 −1 + 𝑧 −1 𝜃𝑀 − 1, 𝑛 𝛽𝑀 − 1, 𝑛 𝐶2𝑅𝑘 OQAM postprocessing 𝑠[𝑚] 𝜃1, 𝑛 𝐶2𝑅𝑘 Analysis Filter Bank 𝑅2𝐶𝑘 𝑑 𝑀 − 1, 𝑛 𝑅𝑒 𝑅2𝐶𝑘 Destaggering FBMC receiver 5G & mmWave Workshop Page 10 OQAM Preprocessing 𝑐𝑜𝑚𝑝𝑙𝑒𝑥 𝑡𝑜 𝑟𝑒𝑎𝑙 𝑐𝑜𝑛𝑣𝑒𝑟𝑠𝑖𝑜𝑛 𝑐𝑘 𝑙 𝑅(. ) 𝜃𝑘 𝑛 = 1, 𝑗, 1, 𝑗, 1, . . ↑2 𝑓𝑜𝑟 𝑘 𝑒𝑣𝑒𝑛 + 𝑐𝑘 𝑙 𝑗𝐼(. ) ↑2 𝑧 −1 𝑅(. ) ↑2 𝑧 −1 ↑2 𝑑𝑘 𝑛 x 𝑥𝑘 𝑛 𝜃𝑘 𝑛 = 𝑗, 1, 𝑗, 1, 𝑗. . + 𝑓𝑜𝑟 𝑘 𝑜𝑑𝑑 𝑗𝐼(. ) 𝜃 pattern 𝑚𝑢𝑙𝑡𝑖𝑝𝑙𝑖𝑐𝑎𝑡𝑖𝑜𝑛 𝑑𝑘 𝑛 x 𝑥𝑘 𝑛 • A time offset of half a QAM symbol period(T/2) is applied to either the real part or the imaginary part of the QAM symbol • For two successive sub-channels, say m and m+1, the offset are applied to the real part of the QAM symbol in sub-channel , while it is applied to the imaginary part of the QAM symbol in sub-channel m+1. 5G & mmWave Workshop Page 11 Poly Phase Network Filter Bank 𝑑0, 𝑛 𝜃0, 𝑛 𝛽0, 𝑛 x x 𝐴0(𝑧 2 ) ↑ 𝑀/2 + 𝑀−1 𝑠𝑚 = ∞ . 𝑘=0 𝑛=−∞ 𝜃1, 𝑛 𝛽1, 𝑛 x x 𝑑1, 𝑛 𝑠𝑚 . . . . . . 𝑧 −1 𝑰𝑭𝑭𝑻 𝐴1(𝑧 2 ) . . . ↑ 𝑀/2 . . . + . . . * Filter overlap factor K : number of multicarrier symbols which overlap in the time domain. 𝑤ℎ𝑒𝑟𝑒: 𝑑𝑘 , 𝑛 𝜃𝑘 , 𝑛 𝑔𝑘 𝑚 − 𝑛𝑀/2 M is number of subcarriers 𝑑𝑘 , 𝑛 𝑖𝑠 𝑡ℎ𝑒 𝑟𝑒𝑎𝑙 𝑣𝑎𝑙𝑢𝑒𝑑 𝑠𝑦𝑚𝑏𝑜𝑙 𝜃𝑘 , 𝑛 𝑖𝑠 𝑗 (𝑘 + 𝑛 ) 𝑔𝑘 (m) is impulse response of the filters * OFDM can be implemented by set K as 1 5G & mmWave Workshop Page 12 Sub-channel Equalization Maximal ratio combined diversity reception t[𝑘] transmitted symbol Channel Estimation 𝑤i H[z] Evaluation of MRC weighted target values 𝑦[𝑘] distorted subcarrier sequence 2 𝑍-1 𝑍-1 𝑣𝑘 𝑛 = X 𝑤0 X + 𝑤1 X + 𝑙=0 𝑤2 𝑤𝑘 , 𝑙, 𝑛 𝑦𝑘 𝑛 − 𝑙 𝑙 = number of tap 𝑣𝑘 𝑛 3-tap Complex FIR frequency sampling-design 5G & mmWave Workshop Page 13 OQAM post processing 𝑟𝑒𝑎𝑙 𝑡𝑜 𝑐𝑜𝑚𝑝𝑙𝑒𝑥 𝑐𝑜𝑛𝑣𝑒𝑟𝑠𝑖𝑜𝑛 𝜃pattern 𝑚𝑢𝑙𝑡𝑖𝑝𝑙𝑖𝑐𝑎𝑡𝑖𝑜𝑛 𝜃𝑘 𝑛 𝑓𝑜𝑟 𝑘 𝑒𝑣𝑒𝑛 𝑥𝑘 𝑛 x 𝑑𝑘 𝑛 ↓2 𝑅(. ) 𝑐𝑘 𝑙 𝑧 −1 + −1 ↓2 𝑗 ↓2 𝑧 −1 𝑗 𝑧 𝜃𝑘 𝑛 𝑓𝑜𝑟 𝑘 𝑜𝑑𝑑 𝑥𝑘 𝑛 x 𝑑𝑘 𝑛 𝑅(. ) 𝑐𝑘 𝑙 + 𝑧 −1 ↓2 5G & mmWave Workshop Page 14 Modeling / Simulation Example for FBMC Systems Random bit generation Symbol Mapping FBMC Reference Source LO source Phase/ Power Modulator Wireless Channel AWGN FO,IQ Im Demodulator FO,IQ Im ADC Jitter / Q noise FBMC Reference Receiver BER/FER Measurem ent TEST O1 {Oscillator@Data Flow Models} REF Im 11010 ••• ••• ••• ••• B1 {RandomBits@Data Flow Models} M1 {Mapper@Data Flow Models} ModType=QPSK [ModType] Re FBMC_Source_1 BERFER {BER_FER@Data Flow Models} QUAD OUT Mod OUT FBMC_Source MAPPER Freq Phase Q I Amp Taps Channel Out Noise Density Freq Phase Q DeMod I Amp DEMAPPER Im FBMC_Receiver Re C4 {CxToRect@Data Flow Models} M2 {Modulator@Data Flow Models} C1 {CommsChannel@Data Flow Models} D3 {Demodulator@Data Flow Models} R3 {RectToCx@Data Flow Models} ModelType=Pedestrian_A A1 {AddNDensity@Data Flow Models} NDensityType=Constant noise density OutputType=I/Q NDensity=10e-12 W [NDensity] FCarrier=1e9 Hz FBMC_Receiver_2 • • • Node ••• ••• Bits D2 {Demapper@Data Flow Models} ModType=QPSK [ModType] Simulation parameters 5G & mmWave Workshop ••• Page 15 Performance Analysis with Real Hardware SYSTEMVUE RFIC DUT M8190A 12 GSa/S Arbitrary Waveform Generator Reference Source I Digital Modem Source for Linear Modulation Frame Structure Idle Preamble Data Payload Automatic waveform creation & download DSSS System X Custom modem design : Replaceable in C++, .m or SV DSP parts formats BBIQ - RF Q Spreading Code Generator BPSK, QPSK, ..., up to 4096-QAM 8-PSK, 16-PSK, 16-APSK, 32-APSK 16-Star QAM, 32-Star-QAM, and Custom APSK Preamble_ModType=BPSK [Preamble_ModType] Payload_ModType=16-QAM [Payload_ModType] I 5G Reference Library Q Digital Modem Receiver Feedward Filter - Decision Device - Feedback Filter RF - BBIQ Reference Receiver M9703A AXIe 12-bit High-Speed Digitizer/Wideband Digital Receiver Interleaving to get 4ch @ 3.2 GSa/s Decision Feedback Equalizer Fast Computation Algorithm CIR--->DFE coefficients {DigMod_ReceiverL_FastDFE} FrameSync_Algorithm=DiffCorr FreqSync_Mode=CIR Corr TrackingAlgorithm=LMS TEST REF BERFER {BER_FER@Data Flow Models} • • Wider BW (63 GHz BW) Higher Sampling (160 GSa/s) BER/FER Measurement Infiniium 90000 Q-Series Oscilloscope 5G & mmWave Workshop Page 16 Agenda – Objective – Multi-Carrier Waveform Techniques • OFDM vs. FBMC • FBMC signal processing • Reference transmitter and receiver modeling, simulation and test – MIMO and Digital Beamforming Techniques • Diversity, Spatial Multiplexing • Multi-user, Massive MIMO • Modeling and Simulation Case studies 5G & mmWave Workshop Page 17 Motivation – Higher requirement for system capacity and spectral efficiency(bits/s/Hz) – To overcome traditional approaches ( expand bandwidth, higher modulation order, multiple access) – The MIMO for better use the spatial resource • The capacity is increased by a multiplication of the number of antennas S C B log 2 1 bit / s M N 5G & mmWave Workshop Page 18 Classification y1 X1 Multi-user Increase system efficiency Multi streams/users Spatial division multiplexing Receive Diversity MIMO Multi-user MIMO . . . . . . X1, X2 y1, y2 Use spatial channel information? -X2, X1* Matrix Space-time block coding (STBC) Transmit Beamforming • Open-loop MIMO • Closed-loop MIMO 5G & mmWave Workshop M >> K >> 1 Massive MIMO Page 19 K terminals y2 X2 Transmit Diversity Massive multi-users S streams Spatial Expansion Spatial multiplexing Improve user throughput M antennas Spatial diversity Improve robustness Transmit Diversity – Use transmit diversity to diminish the effects of fading by transmitting the same information from two different antennas X1, X2 y1, y2 – The data from the second antenna is encoded differently to distinguish it from the primary antenna -X2, X1* – The transmit diversity feature uses ST(space-time) or SF(space-frequency) block encoding to differentiate the signals between Antenna 1 and Antenna 2 – The user equipment (UE) must be able to recognize that the information is coming from two different locations and properly decode the data. SFBC: Tx0 Tx1 f1 f2 x2 x1 x 2 * x1 * STBC: t1 t2 * complex conjugate 5G & mmWave Workshop Page 20 Spatial Multiplexing – Operation Concept • Transmission of multiple spatial data streams over different antennas in the same RB y1 X1 h11 h21 • The dimension of spatial channels is increased and system capacity increased h12 h22 – Relevant signal processing • Perform Layer mapping and Pre-coding to lower the receiver complexity and reduce the signal interference between antennas • Statistic correlation between vector(h11,h12) and vector(h21,h22 ) X2 y2 x: transmitted signal, y: received signal, H: spatial channel matrix, Hij: channel coefficient from the jth transmit antenna and the ith receive antenna. y=Hx y1=h11x1+h12x2+n1 y2=h21x1+h22x2+n2 5G & mmWave Workshop Page 21 Modeling and Simulation for MIMO – MIMO Tx/Rx simulation under Rayleigh fading and AWGN channel – Explore different decoding algorithms and performance evaluation • ML, MMSE-SIC, ZF-SIC, MMSE-Linear, ZF-Linear AWGN Fading Channel I5 {IID_Gaussian@Data Flow Models} StdDev=0.707 V [1/sqrt(2)] Im [ ] Re I6 {IID_Gaussian@Data Flow Models} StdDev=707.1e-6 V [StdDev] Im Re R3 {RectToCx@Data Flow Models} P1 {Pack_M@Data Flow Models} NumRows=2 [ChannelNumRows] NumCols=2 [ChannelNumCols] Format=ColumnMajor I7 {IID_Gaussian@Data Flow Models} StdDev=0.707 V [1/sqrt(2)] R1 {RectToCx@Data Flow Models} [ ] P2 {Pack_M@Data Flow Models} NumRows=2 [RxNumRows] NumCols=1 [RxNumCols] Format=ColumnMajor I2 {IID_Gaussian@Data Flow Models} StdDev=707.1e-6 V [StdDev] DEMAPPER M o d Type Ch a n n e l Re s ponse ••• 11010 ••• ••• [ ] ••• MAPPER B2 {RandomBits@Data Flow Models} Re c o v e re d Data M5 {Mapper@Data Flow Models} ModType=QPSK [ModType] MIMO_Decoder MIMO_Encoder P3 {Pack_M@Data Flow Models} NumRows=2 [TxNumRows] M1 {MIMO_Encoder@5G Advanced Modem Models} NumCols=1 [TxNumCols] Mode=Spatial Multiplexing [Mode] Format=ColumnMajor NumTx=2 [NumTx] Transmit with MIMO coding Re c e i v e d Data M2 {Mpy@Data Flow Models} A4 {Add@Data Flow Models} M3 {MIMO_Decoder@5G Advanced Modem Models} Mode=Spatial Multiplexing [Mode] DecoderMethod=ML [DecoderMethod] ModType=QPSK [ModType] DebugFlag=0 [ ] U1 {Unpack_M@Data Flow Models} NumRows=2 [TxNumRows] NumCols=1 [TxNumCols] Format=ColumnMajor ••• ••• Node ••• ••• Bits D1 {Demapper@Data Flow Models} ModType=QPSK [ModType] MIMO decoding and demapper 5G & mmWave Workshop Page 22 Multi-User MIMO Capacity Comparison SU−MIMO: 𝑀𝑙𝑜𝑔(1 + 𝑆𝑁𝑅) 𝑆𝑁𝑅 MU-MIMO: 𝑀𝑙𝑜𝑔 1 + 𝑀 𝑙𝑜𝑔𝑈 , 𝑈 → ∞ M: TX antenna number, U: Total user number MU-MIMO Scenario Received signal at UE k: The challenge for MU-MIMO is to find orthogonal users and design precoding W to minimize the second term with the restrictions of user grouping, power, latency and complexity Hk: kth user’s channel, W k: weight vector, Sk: data symbol 5G & mmWave Workshop Page 23 Multi-User MIMO Advantages Disadvantages – Multiple access capacity gain (proportional to BS antennas) – BS needs to know channel state information at transmitter (CSIT). The challenges include – more immune to propagation limitations such as channel rank loss, antenna correlation and LOS – Maintain spatial multiplexing gain without large antenna number at terminals • TDD vs. FDD for CSIT • CSI feedback path bandwidth, Code book design – Complexity of the scheduling procedure at BS • User grouping scheduling, power allocation and latency requirements 5G & mmWave Workshop Page 24 Modeling and Simulation for Capacity Estimation Channel transfer matrix I1 {IID_Gaussian@Data Flow Models} StdDev=0.707 V [1/sqrt(2)] Im [ ] Re Capacity measurement User scheduling H Power_Selected P W_Selected W User Scheduler R2 {RectToCx@Data Flow Models} P4 {Pack_M@Data Flow Models} NumRows=1 [NumRx] NumCols=4 [NumTx] Format=ColumnMajor D2 {Distributor@Data Flow Models} BlockSize=1 UserScheduler {MATLAB_Script@Data Flow Models} TotalUsers=100 [TotalUsers] NumTx=4 [NumTx] NumRx=1 TotalPower=10 [SNR] 123 R Channel Capacity H_Selected H SumRate {MATLAB_Script@Data Flow Models} NumTx=4 [NumTx] Noise=1 NumRx=1 A1 {Average@Data Flow Models} NumInputsToAverage=100 S4 {Sink@Data Flow Models} StartStopOption=Samples I3 {IID_Gaussian@Data Flow Models} StdDev=0.707 V [1/sqrt(2)] Simulation condition Sum Capacity – Transmit antenna number (M) : 4 – Total number of user : from 4 to 100 – SNR=10dB – Power allocation by waterfilling algorithm User K: 4->100 5G & mmWave Workshop Page 25 Massive MIMO – Originally envisioned for time division duplex(TDD1), but can potentially be applied in frequency division duplex(FDD) . . . . . . K terminals – Brings huge improvements in throughput and energy efficiency when combined with simultaneous scheduling of a large number of UEs S streams – System Model : M transmit antenna with maximum S streams, K users each with a single antenna Massive multi-users M antennas – The use of a very large number of service antennas operated fully coherent and adaptive M >> K >> 1 Massive MIMO Note1 : Prefer TDD as not enough resources for pilots and CSI feedback. 5G & mmWave Workshop Page 26 Massive MIMO Operation and Challenges Operation Challenges – Acquire Channel State Information from uplink Pilots / Data – Pilot contamination: interference from other cells – Reciprocity calibration and adjustment – Pre-coding1 to support multi-stream transmission – MMSE receiver with beamforming • Maximum ratio combining(MRC) : interference and noise are both white in the space • Interference rejection combining(IRC): colored interference Note1 : Linear pre-coding [maximum ratio transmission(MRT), zero-forcing(ZF)]. Non-linear pre-coding [Dirty paper coding(DPC)], full CSI required • Blind channel estimation? • Coordination and planning? – New pre-coder with low-complexity, low-PAPR – Hardware performance • I/Q imbalance, A/D resolution, PA linearity • Phase noise, clock distribution – Synchronization at low SNR – Understand mmWave MIMO channel 5G & mmWave Workshop Page 27 Modeling and Simulation for Large Number of Antennas Transmit Beamformer Multi-CH Modulator Multi-CH Envelope Adder Multi-CH AWGN Multi-CH De-Modulator Receive Beamformer O1 {Oscillator@Data Flow Models} Frequency=1000000 Hz Power=.010 W T1 {Tx_Beamformer@5G Advanced Modem Models} BeamformingType=Calculate by antenna … NumOfAntx=4 NumOfAnty=4 Dx=0.5 Dy=0.5 Theta=0 ° Phi=0 ° M2 {MultiCh_Demodulator@5G Advanced Modem Models} NumChannels=1 FCarrier=1e6 Hz InitialPhase=0 ° [[0]] AmpSensitivity=1 [[1]] MirrorSignal=NO ShowIQ_Impairments=NO M4 {MultiCh_AddEnv@5G Advanced Modem Models} OutputFc=Center InPhi LO weights Tx Beamformer InTheta quad_output ref MultiChannel Modulator output input input MultiCh Noise Density output MultiChannel Demodulator weights Rx Beamformer input output Env M1 {MultiCh_Modulator@5G Advanced Modem Models} NumChannels=1 FCarrier=1e6 Hz InitialPhase=0 ° [[0]] AmpSensitivity=1 [[1]] ConjugatedQuadrature=NO MirrorSignal=NO ShowIQ_Impairments=NO M6 {MultiCh_AddNDensity@5G Advanced Modem Models} NDensityType=Constant noise density NDensity=0.0 W Scripting • • • • Multiuser scheduling Capacity analysis Quick algorithm implementation and test Calibration R1 {Rx_Beamformer@5G Advanced Modem Models} NumOfTxAnts=16 ABF_Algorithm=Sample Matrix Inversion BlockSize=1024 Plotting • • • Antenna pattern review Interference analysis between different streams Beam pattern vs. precoding analysis(MRT,ZF) 5G & mmWave Workshop Page 28 Channel Sounding / Parameter Extraction / Simulation Channel impulse response Reference transmit signal(chirp/pn) channel H[z] t[𝑘] 𝑧[𝑘] ∑ • • • PDP (Path delay, path loss) AOA, AOD Doppler shift Channel parameters Estimation algorithms CIR correlation Channel sounding Parameters estimation Statistics & modeling • • • Scenario selection Network layout Antenna parameters • • • • • AS AoA/AoD PAS Doppler spectrum Correlation Rician K factor Large/Small scale parameters generation Fading coefficient generation Input signal 𝑥[𝑘] ¤ ESPRIT Subspace based algorithm Maximum estimating number of path is limited by number of Rx, will be fail under NLOS scenario cannot estimate path loss and path delay small computing amount SAGE Maximum likelihood estimation algorithm No limitation for number of path, suitable for both LOS and NLOS scenarios Can estimate all the channel parameters including path loss and path delay of each path Iteration needed, large computing amount faded signal 𝑦[𝑘] SystemVue Simulation 5G & mmWave Workshop Page 29 Prototyping and Testing in Real Time Hardware – Move forward from largely theoretical massive MIMO research to real hardware implementation and test – Open FPGA and download custom algorithms for MIMO and Beamforming – Test and measure in real-time CUSTOM ALGORITHMS FPGA ARRAY M9703 REAL-TIME PROCESSING Up to 40 Channels x 1GHz wide 5G & mmWave Workshop Page 30 Summary – Early research task start with huge math and software simulation – Connected solution between Design/Simulation and Test/Verification – Real time, Multi-channel, wide-band are key themes for 5G research – Hardware-Software-People 5G & mmWave Workshop Page 31