November 4, 2015 5G Waveform & Multiple Access Techniques

1 2015 qualcomm Technologies, Inc. All rights Waveform & Multiple Access TechniquesNovember 4, 20151 2015 qualcomm Technologies, Inc. All rights summaryWaveform & multi- Access Techniques evaluations and recommendations Key Waveform and Multiple - Access design targets Physical layer waveforms comparison Multiple Access Techniques comparison RecommendationsAdditional information on physical layer waveforms Single carrier Waveform Multi-carrier OFDM-based waveformAdditional information on Multiple Access Techniques Orthogonal and non-orthogonal Multiple accessAppendix References List of abbreviations 2015 qualcomm Technologies, Inc. All rights summary 2015 qualcomm Technologies, Inc. All rights Summary4 5G will support diverse use cases-Enhanced mobile broadband, wide area IoT.

2 And high-reliability services OFDM family is well suited for mobile broadband and beyond-Efficient MIMO spatial multiplexing for higher spectral efficiency-Scalable to wide bandwidth with lower complexity receivers CP-OFDM/OFDMA for 5G downlink-CP-OFDM with windowing/filtering delivers higher spectral efficiency with comparable out-of-band emission performance and lower complexity than alternative multi-carrier waveforms under realistic implementations-Co-exist with other Waveform & Multiple Access options for additional use cases and deployment scenarios SC-FDM/SC-FDMA for scenarios requiring high energy efficiency ( macro uplink) Resource Spread Multiple Access (RSMA) for use cases requiring asynchronous and grant-less Access ( IoT) 2015 qualcomm Technologies, Inc.

3 All rights Waveform & Multiple Access are recommended for 5G5eMBBfor Sub-6 GHz Licensed macro uplink Waveform : OFDM, SC-FDM Multiple Access : OFDMA, SC-FDMA, RSMA Unlicensed and small cell uplink Waveform : OFDM Multiple Access : OFDMAWide Area IoT Uplink:- Waveform : SC-FDE- Multiple Access : RSMAmmWave Uplink:- Waveform : OFDM, SC-FDM- Multiple Access : OFDMA, SC-FDMAHigh-Reliability Services2 Uplink- Waveform : OFDM, SC-FDM- Multiple Access : OFDMA, SC-FDMA, RSMAD ownlink recommendation(for all use cases): Waveform : OFDM1 Multiple Access : OFDMA Additional Waveform & Multiple Access options are included to support specific scenarios1. OFDM Waveform in this slide refers to OFDM with cyclic prefix and windowing.

4 2. with scaled frame numerology to meet tighter timeline for high-reliability services 2015 qualcomm Technologies, Inc. All rights & Multiple Access Techniques evaluation and recommendations 2015 qualcomm Technologies, Inc. All rights design across services7eMBB Lower latency scalable numerology Self-Contained TDD subframestructure for licensed & unlicensed spectrum New TDD fast SRS for massive MIMO Integrated Access /backhaul, Area IoT Lower energy Waveform Optimized link budget Decreased overheads Managed meshmmWave Sub6 GHz & mmWave Common MAC Access and backhaul mmWavebeam trackingHigh-Reliability Lower packet loss rate Lower latency bounded delay Optimized PHY/pilot/ HARQ Efficient multiplexingMotivations of Waveform & multi- Access design Support wide range of use cases:-eMBB: higher throughput / higher spectral efficiency -Wide area IoT.

5 Massive number of low-power small-data-burst devices with limited link budget-Higher-reliability: services with extremely lower latency and higher reliability requirements Accommodate different numerologies optimized for specific deployment scenarios and use cases Minimize signaling and control overhead to improve efficiencyEnhanced Mobile Broadband (eMBB) is the anchor technology on to which other 5G services are derived 2015 qualcomm Technologies, Inc. All rights design targets for physical layer waveform8 Keydesign targets Additional detailsHigher spectral efficiency Ability to efficiently support MIMO Multipath robustnessLower in-band and out-of-band emissions Reduce interference among users within allocated band Reduce interference among neighbor operators.

6 Achieve low ACLRE nables asynchronous Multiple Access Support a higher number of smallcell data burst devices with minimal scheduling overheadthrough asynchronous operations Enableslower power operationLower power consumption Requires low PA backoffleading to high PA efficiencyLower implementation complexity Reasonable transmitter and receiver complexity Additional complexity must be justified by significant performance improvements 2015 qualcomm Technologies, Inc. All rights design targets for Multiple Access technique9 Keydesign targetsAdditional detailsHigher network spectral efficiency Maximize spectralefficiency across users and base stations Enable MU-MIMOLink budget and capacity trade off Maximize link budget and capacity taking into consideration their trade off as well as the target use case requirementsLower overhead Minimize protocol overhead to improve scalability, reduce power consumption, and increase capacity Lower control overhead 2015 qualcomm Technologies, Inc.

7 All rights refresh on OFDMO rthogonal Frequency Division Multiplexing10 DataSerial to ParallelIFFTF oundation to OFDM SynthesisCyclic Prefix (CP) InsertionWindowing/Filtering0s0sTo RFSimplified OFDM Waveform synthesis for a transmitterCoding & ModulationOFDM-based waveforms are the foundations for LTE and Wi-Fi systems todayWindowing reduces out-of-band emissionsHelps maintain orthogonality despite multipath fadingData transmitted via closely-spaced, narrowband subcarriers IFFT operation ensures subcarriers do not interfere with each otherCPBandwidthTimeTransmitted Waveformafter windowingIFFT outputCPTime 2015 qualcomm Technologies, Inc. All rights family well suited to meet the evolving requirements11 Additional Waveform & Multiple Access options can complement OFDM to enable more use casesAsynchronous multiplexingCan co-exist with other Waveform /multi- Access within the same framework to support wide area IoTMIMO zzzzzzzzzzzzHigher spectral efficiencyEfficiently support MIMO spatial multiplexing with wide bandwidths and larger array sizesLower out-of-band emissionsWindowing effectively enhances frequency localizationLower complexityLower complexity receivers even when scaling to wide bandwidths with frequency selectivityLower power consumptionSingle-carrier OFDM Waveform for scenarios with higher power efficiency requirements

8 2015 qualcomm Technologies, Inc. All rights OFDM-based waveforms consideredDifferent implementation options and optimizations12 WaveformsABIFFTCDECP-OFDM +WOLA1 CP SC-FDM + WOLA CP UFMC ZG FBMC Zero-tailSC-FDM DataSerial to ParallelZeroes at headZeroes at tailZero-tail PadDFT PrecodingOFDM Synthesis(IFFT)CP or Zero-guardWindowing(prototype filter)BandpassFilter00To RFOptional blocks1 Weighted OverLapand Add (WOLA) Windowing technique popular in 4G LTE systems todayLTE ULLTE DL 2015 qualcomm Technologies, Inc. All rights of single-carrier waveforms13 WaveformsProsConsConstant envelope( ,GMSK in GSM and BluetoothLE; MSK in Zigbee) 0dB PAPR Allow asynchronous multiplexing Good side lobe suppression (GMSK) Lower spectral efficiencySC-QAM(inEV-DO, UMTS) Low PAPR at low spectral efficiency Allow asynchronous multiplexing Simple Waveform synthesis Limited flexibility in spectral assignment Non-trivial support for MIMOSC-FDE Equivalentto SC-QAM with CP Allow FDE processing Similar as SC-QAM ACLR similar to DFT-spread OFDMSC-FDM1(inLTE uplink)

9 Flexible bandwidth assignment Allow FDE processing Higher PAPR and worse ACLR than SC-QAM Need synchronous multiplexingZero-tail SC-FDM2 Flexible bandwidth assignment No CP, but flexible inter-symbol guard Better OOB suppression than SC-FDM without WOLA Need synchronous multiplexing Need extra control signaling Lack of CP makes multiplexingwith CP-OFDM less flexible1. Also referred to as SC DFT-spread OFDM. 2. Also referred to as Zero-tail SC DFT-spread OFDM 2015 qualcomm Technologies, Inc. All rights of OFDM-based multi-carrier waveforms14 WaveformsProsConsCP-OFDM(in LTE existing implementations typically include WOLA to meet performance requirements) Flexible frequency assignment Easy integration with MIMO High ACLR side lobedecays slowly Need synchronous multiplexingCP-OFDM with WOLA(in existing LTE implementations) All pros from CP-OFDM Better OOB suppressionthen CP-OFDM Simple WOLA processingUFMC Better OOB leakage suppression than CP-OFDM (butnot better than CP-OFDM with WOLA) ISI from multipath fading(no CP) Higher Txcomplexity than CP-OFDM Higher Rx complexity (2x FFT size)

10 Than CP-OFDMFBMC Better than CP-OFDM with WOLA (but the improvement is reduced with PA nonlinearity) High Tx/Rx complexity due to OQAM ( Waveform is synthesized per RB) Integration with MIMO is nontrivial Subject to ISI under non-flat channelsGFDM Same leakage suppression as CP-OFDM with WOLA Complicated receiver to handle ISI/ICI Higher block processing latency (no pipelining) Multiplex with eMBBrequires large guard band 2015 qualcomm Technologies, Inc. All rights of Multiple Access techniques15 Multiple accessProsConsSC-FDMA(in LTE uplink) With PAPR/coverage Multiplexing with OFDMA Need synchronous multiplexing Link budget loss for large number of simultaneous usersOFDMA(in LTE downlink) No intra-cell interference higher spectral efficiency andMIMO Need synchronous multiplexing Link budget loss for large number of simultaneoususersSingle-carrierRSMA Allow asynchronous multiplexing GrantlessTx with minimal signaling overhead Link budget gain Not suitable for higherspectral efficiencyOFDM-basedRSMA GrantlessTx with minimal signaling overhead Need synchronous multiplexingLDS-CDMA/SCMA Allow lower complexityiterative message passingmultiuser detection (whenthere are small number of users)