MIMO Parallel Channel Sounder Dr. Yang Yang Shanghai Research Center for Wireless Communications Key Lab of Wireless Sensor Network and Communication Chinese Academy of Sciences 上海市浦东新区海科路 100 号 8 号楼 4 楼,201210 电话 :0 21-60213003 传真 :0 21-60213000 4/F, Building 8, 100 Haike Rd, Pudong, Shanghai 201210, China Tel: + 86-21- 60213003 Fax: + 86-21- 60213000
System design 8x8 MIMO Parallel Channel Sounder 2
Content Motivation System design Key technology Future work Company Logo 3
Motivation Background and motivation National Science and Technology Major Project ( 2014ZX03003012-001) Databank for channel measurement data (Open source community ) Difference between traditional channel sounder and parallel sounder Lack of professional channel measurement equipment New Scenarios defined by IMT-2020 4
Motivation New scenarios Dense residential zone Office Aircraft Large stadium Public place Suburb Metro Expressway High-speed railway Highrise Backhaul 5
Content Motivation System design Key technology Future work Company Logo 6
System design System Design Requirement 1. Scenarios: distance range >1km; 3D channel; high speed (350km/h). 2. High-precision synchronization between multiple channels 3. Raw data real-time storage 4. Calibration for MIMO transceiver: 64 channels and vector signal transceiver system response 5. Post data processing for multichannel: interference cancellation and parameter estimation Rx Rx Tx switching seq 1 2 3 1 2 3 4 Tx switching seq 1 2 3 1 2 3 4 TDM Parallel Rx switching seq time Rx switching seq time 7
System design System Framework 8
System design Transmitting Unit Tx:8*8 MIMO TX Part PXIe PC controller PXI GPS Receiver GPS Antenna 10MHz CLK PXIe chassis cascade Rubidium atomic clock PXIe VST PXIe Timing & Sync
System design Receiving Unit Rx:8*8 MIMO RX Disk Streaming PXIe PC controller PXI GPS Receiver PXIe cascade + Disk Array (SSD) GPS Antenna 10MHz CLK PXIe chassis cascade Rubidium atomic clock PXIe VST PXIe Timing & Sync
System design Software solutions User Application Post data processing Instrument Driver Library Windows OS FPGA MIMO Generation MIMO Calibration MIMO Acquisition and Disk Streaming HW 11
System design Key parameters Parameter PropSound WiCO Center frequency / bandwidth <6GHz <6GHz RF Channel /Tx(Rx) 1 8 Channel sounder method TDM MIMO Parallel RF bandwidth 120Mhz 200Mhz Transmitted power per antenna 27dBm~40dBm 15dBm~40dBm dynamic range 40db 36db multipath time resolution 8.33ns 5ns maximum Doppler shift 30~60Hz 2kHz maximum detectable speed of an object <30kmh >350kmh Maximum impulse response 20.48us 20.48us Data stored CIR Raw Data/CIR Parameter method SAGE Parallel SAGE Implement platform customized SDR 12
System design Advantages First 8x8 parallel channel sounder Suitable for dynamic MIMO channel with high velocity Dynamic range comparable to TDM sounder Flexible and adaptive with SDR platform Interference cancellation by PS-SAGE Transferable to MIMO channel emulator 13
Content Motivation System design Key technology Future work Company Logo 14
Key technology Channel synchronization Challenge : Crosstalk, non-orthogonal error, path difference raise the phase difference Pico second level synchronization precision for accurate estimation Phase coherent Signal generation & Acquisition Implement: T1= 通道 1 上升沿的时间差 T2= 通道 N 上升沿的时间差 T2=T2-T1 Timing jitter can be reduced to 30ps among 8 channels of MIMO parallel Channel sounder The synchronization accuracy is less 1ns of Keysight M9391A (PXIeVSA) and M9381A (PXIe VSG) 同步脉冲 10MHz 参考时钟 /SSPC 通道 1 的采样时钟 -60MHz STRC-20MHz 10MHz 参考时钟 /SSPC 通道 N 的采样时钟 -30MHz STRC-20MHz 15
Key technology Real-time data streaming P2P link between FPGA and SSD Zero-copy technology to reduce delay TDMS (Technical Document Management System) method for storage and data organization 16
Key technology Parallel channel calibration 10W PA Y RSTX Y RHTX N Using VNA to get S (cali component) Using calibration data to get R (receiver) and T (transmitter) Using R and T to reconstruction signal MAX ( P( Y RH ( chanpara) TX )) chanpara Using ML to estimation channel parameter
Key technology Post data processing HRPE:PS-SAGE Parallel Sounder-SAGE(PS-SAGE) Considering coherence among the different channel Antenna pattern measurement using N paths transmitter and one path receiver Robustness in non-ideal orthogonal channels since channel disturbance Low complexity process Baseband signals SAGE parameter estimation Impulse response calibration of RF channel Calibration data HRPE:High Resolution Parameter Estimation
Key technology Parameters estimation Using calibration data to correct different delay among multichannel Parameter estimation is accurate Reconstruction signal spectrum is highly similar to original signal spectrum
Content Motivation System design Key technology Future work Company Logo 20
Future work Measurement campaign chamber canteen stade hall country Public marketplaces campus 21
Future work New function and capability Channel measurement Databank 1.Verification and Comparison With ray tracing software With channel emulator 2.Extend to 64*64 Parallel & Serial 3.mmWave Channel measurement 2GHz bandwidth 60-110GHz 22
Thank you for your attention! Yang Yang,yang.yang@wico.sh 23