Development Status and Future Trend of MIMO OTA Test Dr. Peter Liao ( 廖兆祥博士 ) Secretary, CTIA MIMO OTA Sub Group (MOSG) Electronics & Communication Lab Global OTA Technical Leader, Ph.D. SGS Taiwan Ltd. E-mail: peter.liao@sgs.com 2017/11/15 & 2017/11/16
Outline Why MIMO OTA Testing Role of Spatial Channel Models MIMO OTA Test Plan Development Status (3GPP/CTIA/CCSA) Summary and Future Trends 2
How is a MIMO OTA work? MIMO is the LTE development trend for high-data-rate device MIMO provides stable data throughput capability. MIMO can reduce the multipath fading effect. LTE will implement MIMO to increase the data throughput rate. SISO Tx Rx MIMO Tx Rx Spatial Sparser Spatial Demux Combiner Tx Rx 3
Antenna Performance Measurement for Mobile Phone VSWR 4
OTA: Over-the-Air What s the OTA Measurement? The purpose is to measure the 3-dimensions (X, Y, Z) antenna pattern for transmit power and receiver sensitivity for wireless devices. 5
OTA Measurement Methods FS: BHHL: BHHR: HL: HR: 6
EUT Coordinate System-MS Hand Right (HR): 7
EUT Coordinate System - Laptop 8
EUT Coordinate System - Tablet 9
SISO and the RF Environment 10
MIMO and the RF Environment 11
SISO OTA tests: OTA test: SISO vs MIMO Mostly related to antenna pattern. TIS, Total Isotropic Sensitivity and TRP, Total Radiation Power test. MIMO OTA test: MIMO performance is all about correlation (Antennas, channels,..) There are more than one antenna, the multipath fading cause the receiving signal at every antenna to be different. MIMO device benefits from this phenomenon to have more data streams. Standard channel model is necessary at MIMO OTA test. Throughput performance test is the only figure of merit.. 12
Throughput (Mbps) MIMO is all about Correlation! 4G/5G mobile terminals utilize multi-antenna techniques to improve performance, in which spatial correlation plays the key role. Spatial correlation is a function of antenna and propagation,... Evaluate the end-user experience of the final product, e.g., in terms of data throughput, against realistic radio channel conditions in OTA environment. Data throughput is the only figure of merit. Throughput results, ILIT P3 GS4 B2 DML (UMa), ETS CE2 r01 35 Multipath 30 Good or bad? 0 deg 30 deg 60 deg 25 90 deg 120 deg Simultaneously transmits two independent, spatially-diverse data streams. 20 150 deg 180 deg 210 deg 240 deg 270 deg 300 deg 330 deg -96-95 -94-93 -92-91 -90 RS EPRE (dbm/15 khz) 13
MIMO Antenna Performance: Correlation 14
What is MIMO OTA? Test conditions (e.g. channel model) DUT = Device Under Test Channel model creates the typical radio conditions in which the DUT operates Chamber presents the test environment under which the DUT is tested 15
Multi-Probe Anechoic Chamber (MPAC) Anechoic Chamber Shielded room Microwave absorbers Turn-table Controllers Dual Polarized antennas Link /Calibration antennas Mounting Equipment Base station controller (COMM) Channel Emulator (Propsim) VNA Software Test Executive MIMO OTA Software Option 3GPP Channel Models 16
Outline Why MIMO OTA Testing Role of Spatial Channel Models MIMO OTA Test Plan Development Status (3GPP/CTIA/CCSA) Summary and Future Trends 17
What Should The Environment Mimic Dense urban environment Suburban & rural environments Indoor environments Approved 3GPP Channel models: SCME UMa/SCME UMi 18
Where The Device Performs Radio channel is the vital connection between the device and the BS Radio waves intract with objects in the propagation path resulting in It is very important to adequately model the propagation conditions with a test setup to ensure valid performance testing 19
Understanding the Channel Emulator Channel Emulator simulates wireless channel, including geometric information about the location of scatters channel behavior AOA/AOD Angular Spread PDP (power delay profile) Delay Spread Doppler Effect Frequency Spread Real World!!! 20
MIMO OTA Principles Basic Idea of Mapping of the Signals onto Probe Antennas power N v N delay 1 MS 1 BS 2 2 2 1 MS Angle of Arrival (AoA) and AoA spread are mapped onto OTA antennas in the chamber 21
What parameters are described in Space channel model? SCME Urban macro-cell (UMa) Cluster # Delay [ns] Power [db] AoD [ ] AoA [ ] 1 0 5 10-3 -5.2-7 82.0 65.7 2 360 365 370-5.2-7.4-9.2 80.5 45.6 3 255 260 265-4.7-6.9-8.7 79.6 143.2 4 1040 1045 1050-8.2-10.4-12.2 98.6 32.5 5 2730 2735 2740-12.1-14.3-16.1 102.1-91.1 6 4600 4605 4610-15.5-17.7-19.5 107.1-19.2 Delay spread [ns] 839.5 Cluster AS AoD / AS AoA [ ] 2/35 Cluster PAS shape Laplacian Total AS AoD / AS AoA [ ] 7.9/62.4 Mobile speed [km/h] / Direction of travel [ ] 30/120 XPR NOTE: V & H components based on assumed BS antennas 9 db Mid-paths Share Cluster parameter values for: AoD, AoA, AS, XPR 22
3GPP SCME Multi-Cluster Channel Models SCME Urban micro-cell ( UMi) Cluster # Delay [ns] Power [db] AoD [ ] AoA [ ] 1 0 5 10-3.0-5.2-7.0 6.6 0.7 2 285 290 295-4.3-6.5-8.3 14.1-13.2 3 205 210 215-5.7-7.9-9.7 50.8 146.1 4 660 665 670-7.3-9.5-11.3 38.4-30.5 5 805 810 815-9.0-11.2-13.0 6.7-11.4 6 925 930 935-11.4-13.6-15.4 40.3-1.1 Delay spread [ns] 294 Cluster AS AoD / AS AoA [ ] 5 / 35 Cluster PAS shape Laplacian Total AS AoD / AS AoA [ ] 18.2 / 67.8 Mobile speed [km/h] / Direction of travel [ ] 3, 30 / 120 XPR NOTE: V & H components based on assumed BS antennas Mid-paths Share Cluster parameter values for: 9 db AoD, AoA, AS, XPR SCME Urban macro-cell (Uma) Cluster # Delay [ns] Power [db] AoD [ ] AoA [ ] 1 0 5 10-3 -5.2-7 82.0 65.7 2 360 365 370-5.2-7.4-9.2 80.5 45.6 3 255 260 265-4.7-6.9-8.7 79.6 143.2 4 1040 1045 1050-8.2-10.4-12.2 98.6 32.5 5 2730 2735 2740-12.1-14.3-16.1 102.1-91.1 6 4600 4605 4610-15.5-17.7-19.5 107.1-19.2 Delay spread [ns] 839.5 Cluster AS AoD / AS AoA [ ] 2 / 35 Cluster PAS shape Laplacian Total AS AoD / AS AoA [ ] 7.8 / 62.6 Mobile speed [km/h] / Direction of travel [ ] 3, 30 / 120 XPR NOTE: V & H components based on assumed BS antennas 9 db Mid-paths Share Cluster parameter values for: AoD, AoA, AS, XPR 23
What is the meaning of each parameter or word such as Cluster, AoA,AoD,AS and so on? 24
Six Clusters for power and delay 25
3GPP SCME Multi-Cluster Channel Models -UMA PDP 1 3 2 4 5 6 v N N 1 MS 1 BS 2 2 2 1 MS Angle of Arrival (AoA) and AoA spread are mapped onto OTA antennas in the chamber 26 26 26
Angle of Arrival (AoA) and Angle of Departure (AoD) 27
Cluster Power Angular Spectrum (PAS) Shape 28
Cluster Angular Spread (AS) AoD/AS AoA 29
Mobile Speed/Direction of Travel 30
Channel Models Radio channel is characterized in four domains Time Frequency Space Polarization polarization 31
The Role of Channel Emulator Channel Emulator creates the desired radio channel conditions into the lab. Multipath propagation (per-path delay, Doppler, AoD, AoA, polarization) Antenna effect (BS and MS side in conductive test; BS side in OTA) Noise and interference conditions when applicable Mapping of radio channel conditions onto the number of probe antennas in anechoic chamber. 32
Throughput (Mbps) Figure of Merit- SIR vs. Throughput Good Device Less Power need to achive High Tput Higher Power need to achieve same Tput Bad Device Maximum Throughput (100%) : 35.424 Mbps 35 Throughput results, ILIT P3 GS4 B2 DML (UMa), ETS CE2 r01 Throughput Assement Point 95 % of Max Tput 33.65 Mbps Throughput Axis: Measured Throughput (in Mbps) 30 25 20 0 deg 30 deg 60 deg 90 deg 120 deg 150 deg 180 deg 210 deg 240 deg 270 deg 300 deg 330 deg Throughput Assement Point 90 % of Max Tput 31.88 Mbps Throughput Assement Point 70 % of Max Tput 24.8 Mbps 24 25 26 27 28 29 30 RS EPRE (dbm/15 khz) SIR in db -96-95 -94-93 -92-91 -90 (to at least 0.5 db resolution) 33
Figure of Merit Power vs. Throughput Good Device Less Power need to achive High Tput Higher Power need to achieve same Tput Bad Device Throughput Axis: Measured Throughput (in Mbps) Performance difference between Good and Bad devices What is the cutoff limit Throughput Assement Point 70% of Max Tput Power Axis : Input Power in dbm/15khz 34
Multi-Probe Anechoic Chamber (MPAC) Integrated by: 35
Capturing Device Usage Patterns AC Results Throughput (in Mbps) RC Results Antenna designs and polarizaiton can affect performance of upto 8dB EPRE dbm/15khz Unable to distinguish between the different orientations when measured in isotropic environment Methodology should be able to validate peformance across different positions. Different devices provide different monitization models. Source: 1. MOSG131009; Update results on DUT Polarization discrimination among MIMO OTA test methods 2. MOSG140414: Measurement campaign on AC MC Boundary Array, comparing B13 devices in different mechanical modes and test methodologies 36
Key Benefits of the Anechoic Chamber Methodology 1 2 3 4 Scalability Polarization Discrimination Active Antenna Systems Future Proof CA, 3D, UL, VDT, 5G,.. Start small and expand as the needs raise. Performance against common device usage patterns Test evolving innovations Ideal Investment protection 37
Outline Why MIMO OTA Testing Role of Spatial Channel Models MIMO OTA Test Plan Development Status (3GPP/CTIA/CCSA) Summary and Future Trends 38
CPWG Organization & Industry Relations Update 39
Certificate of Appreciation (May 2017) 40
CATLs by Testing Scope Scope Number of Labs CDMA Conformance 7 CDMA Cabled IOT 3 LTE Cabled IOT 4 LTE CA Cabled IOT 3 LTE Conformance 3 MIMO OTA Performance 21 SISO OTA Performance 75 Converged Device 50 Device Hardware Reliability 4 HAC 11 Battery Safety 27 Battery Life 5 Bluetooth Compatibility 11 41
MIMO Authorized CATL s ATMC Bureau Veritas ADT - Xindian District BV CPS ADT Korea Ltd. Suwon East Cisco Systems, Inc. CTTL Beijing BDA CTTL Shenzhen - Futian District DEKRA Testing and Certification, SAU Electro Magnetic Test Integrated Service Technology Inc. Taiwan PCTEST San Jose SEQAL - Korea 42
MIMO Authorized CATL s (Cont.) SGS Branchburg SGS Korea - Yongin SGS North America Inc. (World Trade Drive, San Diego) SGS RF Technologies Inc. SGS Taiwan Ltd. Hwaya District SGS Taiwan Ltd. NeiHu District SGS-CSTC Standards Technical Services Co., Ltd (ShenZhen) Sporton International Inc. (KunShan) Sporton International Inc. (Tao Yuan Hsien II) TTA Korea 43
Currently 109 CATLs Throughout World 37 in North America 44
Currently 109 CATLs Throughout World 7 in Europe 45
Currently 109 CATLs Throughout World 65 in Asia 46
Test Plan Download and CATL List The CTIA Test Plan for 2x2 Downlink MIMO and Transmit Diversity Over-the- Air Performance will be required for certification testing on April 1, 2017. You can find the test plan here: http://www.ctia.org/initiatives/certification/certification-test-plans A List of CTIA Authorized Test Labs for MIMO testing can be found here: http://www.ctia.org/initiatives/certification/ctia-authorized-test-labs
CTIA 2x2 DL MIMO OTA Test Plan V1.1 CTIA MIMO V1.1 was published in Aug. 2016, and enforced on April 1, 2017. LTE MIMO SIR vs T-put testing by Multi-Probe Anechoic Chamber (MPAC) method. Free space, M-channel, TM3 with 64QAM, UMa channel model and two positions (Portrait and Landscape tilt up 45 deg). Portrait tilt up 45 deg Landscape tilt up 45 deg 48
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MIMO OTA Test Frequencies 50
Example for MIMO OTA Data Table Format Device Orientation Portrait Azimuth Position (degrees) Downlink SIR @ 95% Throughput (db) Downlink SIR @ 90% Throughput (db) Downlink SIR @ 70% Throughput (db) 0 28.89332933 27.42520586 25.14332431 30 29.36221591 27.68318966 25.24059561 60 29.58321429 27.84056474 25.29147412 90 29.91335979 27.9534965 25.28167268 120 28.750251 27.34237379 25.04394439 150 28.53490991 27.12758398 24.90965395 180 28.55642145 27.17285041 24.89544092 210 28.61071429 27.2016496 24.90190495 240 29.2995283 27.62408537 25.15231565 270 29.22060811 27.68662864 25.29281116 300 29.13331025 27.73719441 25.45560854 330 29.25903263 27.84333013 25.47891313 MARSS (P Marss ) 29.11301562 27.56186704 25.17834114 51
Throughput (Mbps) The EUT s Pass/Fail Performance a) The EUT must meet 70% throughput in all 12 azimuthal orientations. If the EUT fails to meet this criterion, the EUT shall fail the MIMO OTA test. b) The EUT must meet 95% throughput in at least 10 of the 12 azimuthal orientations. If the EUT fails to meet this criterion, the EUT shall fail the MIMO OTA test. Maximum Throughput (100%) : 35.424 Mbps 35 Throughput results, ILIT P3 GS4 B2 DML (UMa), ETS CE2 r01 Throughput Assement Point 95 % of Max Tput 33.65 Mbps Throughput Axis: Measured Throughput (in Mbps) 30 25 20-96 -95-94 -93-92 -91-90 RS EPRE (dbm/15 khz) 0 deg 30 deg 60 deg 90 deg 120 deg 150 deg 180 deg 210 deg 240 deg 270 deg 300 deg 330 deg 24 25 26 27 28 29 30 SIR in db (to at least 0.5 db resolution) Throughput Assement Point 90 % of Max Tput 31.88 Mbps Throughput Assement Point 70 % of Max Tput 24.8 Mbps 52
Operators start to request MIMO OTA test T-Mobile USA will add MIMO OTA test from Q4 2017. Sprint will add CTIA MIMO OTA test plan from May 2017. Verizon already request MIMO OTA test from April 2017. AT&T accept CATL to do certification test based on CTIA test plan 1.1 from April 2017. Vodafone request MIMO OTA test from 2017. One of JP carriers request MIMO OTA test from 2014. 53
MIMO Test Requirement for Operators Operator Test Method Timeline AT&T MPAC CATL can test MIMO OTA by MPAC From April, 2017 Verizon Wireless MPAC From 4/17, 2017, A-ECC is retired Sprint MPAC Will be added in May, 2017 T-Mobile USA MPAC From Q4, 2017 Vodafone MPAC From 2017 One of JP carriers MPAC and RC From 2014 Orange TBD TBD China MPAC TBD 54
Three prioritised orientations for MPAC in 3GPP Portrait tilt up 45 deg Landscape tilt up 45 deg Face up 55
Standardization Activities Addressing MIMO OTA Spring 2013 October 2008 March 2009 2009 May 2011 MOSG SWG2.2 RAN4 MIMO OTA COST 56
CTIA MIMO OTA test plan 1.1-summary 使用 SCME UMa 通道模型進行 FDD(10MHz) 或 TDD(20MHz) LTE 在 TM3 模式下的 Down Link 2x2 的 MARSS 測試系統僅可使用 MPAC,Multi-Probe Anechoic Chamber 架構, 如 ETS 或 Satimo Test Zone 為 1λ 使用控制 SIR 變化的方式進行 data throughput 測試 待測手機擺在轉檯上, 傾斜 45 度,Portrait 或 Landscape 擺法 在 Ψ 平面上每 30 度進行一次測試, 總共要進行 12 次測試, 再取平均值 測試目標為找到 (70%,90%,95%) peak throughput 時的 SIR 數值, 此為其 MARSS, MIMO Average Radiated SIR Sensitivity Portrait Landscape 57
3GPP RAN4 activities R4-1611000(Response LS to GCF), TR37.977, R4-1702934 (WF) 3GPP MIMO OTA test plan uses:: UE noise-limited environment (CTIA uses SIR) Transmission Mode 3 (TM3) Umi, Urban Micro channel model (CTIA uses Uma, Urban Macro) 3GPP RAN4 update on Rel-13 work: 1. Final harmonization cannot be successfully claimed. But potential for harmonization can be found. In this situation, a single method shall be selected according to WID, while work on improving harmonization is deemed possible and needed 2. Select MPAC methodology, and start new activity on performance requirement phase for MPAC 3. Select UMi channel model, and inverse averaging. Option C 4. Select the following KPIs: 70% and 95% 58
CCSA MIMO OTA 行標標準號 YD/T 2869.1-2015 终端 MIMO OTA 天线性能要求和测量方法 內容與架構大至上與 CTIA 的 test plan 相同, 僅有部分細節不同. 僅可使用 MPAC 系統進行測試 包括 20MHz 頻寬的 TDD(38,39,40,41) 與 FDD(1,3) LTE 兩種模式 待測手機擺在轉檯上, 傾斜 45 度,Portrait,Landscape 或 face up 擺法 使用 SCME UMa 與 UMi 兩種通道模型 使用 RS-EPRE power sweep 方式測試 TM3 的 sensitivity, 不使用 SIR 在 Ψ 平面上每 30 度進行一次測試, 總共要進行 12 次測試, 再取平均值 測試目標為找到 (70%, 90%) peak throughput 時的 RS-EPRE 數值, 此為其 sensitivity 59
Different settings between CTIA & CCSA Parameters & Settings CTIA CCSA 1 Measurement parameters TM3 TM2 SIR Power(RS-EPRE) Power(RS-EPRE) N/A 2 Outage Level 95%, 90%,70% 90%, 70% 3 Substitution method (for failing azimuthal orientations) YES NO 4 Channel Model Uma Umi 5 Minimum Number of Subframes 20000 10000 6 7 8 Bandwidth TBS index settings FDD TDD FDD TDD 10MHz 20MHz 20MHz 20MHz Subframe 0~4,6~9: 16 Subframe 5: unused Subframe 0/1/4/6/9: 16 Subframe 5: unused Other subframes are for UL. Max Power/ALL+1dB Uplink Transmit Power Control P-Max = +13dBm N/A (Class 3 UE) References: [1] CTIA, Test Plan for 2x2 Downlink MIMO and Transmit Diversity Over-the-Air Performance, Version1.1, August, 2016. [2] CCSA(China Communications Standards Association), YD/T 2869.1 Performance requirement and measurement method for MIMO antenna terminal, Part 1:LTE wireless terminal, July, 2015. 60
Outline Why MIMO OTA Testing Role of Spatial Channel Models MIMO OTA Test Plan Development Status (3GPP/CTIA/CCSA) Summary and Future Trends 61
Summary 從 2017 年 4 月 1 日開始, PTCRB 認證測試 CTIA 2x2 DL MIMO OTA. MIMO OTA 系統中通道模擬器負責在暗室中產生 SCME UMa 通道模型, 並產生 SIR 控制所需之 AWGN 訊號. MIMO OTA 測試需要有 multi-path 環境 : MIMO is all about correlation. 測試之前先作 SIR validation, 確認系統正確校驗. MPAC 是 LTE MIMO OTA 認證測試唯一被核准使用之架構. MPAC 可以升級用於未來的 CA, VDT, 3D, 5G (<6GHz) 應用. WiFi 沒有制定 MIMO OTA 規範, 只需 TIS, TRP 及 Desense 測試. 62
Summary Radio channels are a vital part of the OTA testing. Anechoic Chamber based solution: Technically most Accurate, Scalable, deterministic, Future proof. Reverberation Chamber based Solution: quick, fast, easy to down select and evaluate devices. Different methods are made for different needs. Several round-robin tests are going on at our own facility. We actively participate CTIA and 3GPP to finalize MIMO test plan. MIMO is emerging technology. We continuously work MIMO OTA solutions for future development. 63
Test Plan Development for CTIA MIMO OTA V1.2/V1.3 Finalize MIMO IL/IT test devices in 2017 and start IL/IT in 2018 Release of v1.1.1 (editorial and clarification updates) on September 30, 2017 Notebooks is not currently normative to be tested. Finalize v1.2 (Release Date of v1.2: December, 2017) TDD SIR validation procedure and other updates for TDD Additional mechanical use cases (narrow and wide hands) Orientation requirements for non-smartphone devices VRMC test (variable reference measurement channel) Addition of Band 66 Release Date of v1.3: June ~ August, 2018 2x4, 4X2 and 4X4 MIMO OTA Larger quiet zone for laptops Investigate the addition of a spatial interferer 64
Addition of Band 66 to v1.2 of the CTIA MIMO OTA Test Plan If the device supports both Band 2 and Band 25, then testing is only required in Band 25. If the device supports both Band 12 and Band 17, then testing is only required in Band 12. If the device supports both Band 4 and Band 66, then testing is only required in Band 66. If the device supports both Band 5 and Band 26, then testing is only required in Band 26. Operating Band DL Channel Bandwidth (MHz) DLChannel Number DL Center Channel Frequency (MHz) l (m) at Center DL Channel Test Volume Sphere Radius (m) 2 10 900 1960 0.153 0.076 4 10 2175 2132.5 0.141 0.070 5 10 2525 881.5 0.340 0.170 7 10 3100 2655 0.113 0.056 12 10 5095 737.5 0.406 0.203 13 10 5230 751 0.399 0.200 14 10 5330 763 0.393 0.196 17 10 5790 740 0.404 0.203 25 10 8365 1962.5 0.153 0.076 26 10 8865 876.5 0.342 0.171 30 10 9820 2355 0.127 0.064 66 10 66886 2155 0.139 0.070 65
8 Dual Polarization Probes System for 2x2, 4x2 and 4x4. Use 16 antennas to double test zone. Anechoic Chamber Shielded room 4x2 or 4x4 Equipment Base station controller (COMM) Channel Emulator (Propsim) VNA 2x2 Software Test Executive MIMO OTA Software Option 3GPP SCME Uma Channel Models Microwave absorbers Turn-table Controllers Dual Polarized antennas Link /Calibration antennas Amplifier Units. 66
Thank you very much for your attention!! Any Questions? 67