5G New Radio (NR) : Physical Layer Overview and PerformanceIEEE Communication Theory Workshop - 2018Amitabha GhoshNokia Fellow and Head, Radio Interface GroupNokia Bell LabsMay 15th, 20181

5G New Radio : Key FeaturesFeatureBenefitFeatureBenefitUsage of sub 6GHz andmmWave spectrum10x.100x more capacityAdvanced ChannelCodingLarge data block supportwith low complecxityUE agnostic MassiveMIMO and beamformingHigher Capacity andCoverageAggregation of LTE 5G carriersHigher data rate withsmooth migrationLean carrier designLow power consumption,less interferenceIntegrated Access andBackhaulGreater coverage @mmWave with lower costFlexible frame structureLow latency, highefficiencyFlexible connectivity,mobility and sessionsOptimized end-to-end forany servicesScalable OFDM basedair-interfaceAddress diverse spectrumand servicesBeamformed Controland Access ChannelsGreater CoverageScalable numerologySupport of multiplebandwidths and spectrumHigher Spectral UsageEnhanced Efficiency2 Nokia 2017

Potential 5G Bands in (Early) 5G DeploymentsMacroAuction2019Auction20193600 MHzLTE/5GNorth America700 MHzLTE/5GAPAC, EMEA, LatAm3.3-3.4LTE/5GAPAC, Africa, urope4.55GJapanChina285GUS, KoreaJapan395GUS24.25-27.55GWRC-19 band31.8-33.45GWRC-19 band (Fra, UK) 40, 50, 705GWRC-19 bandsFull coverage with 1GHzDense urban high dataratesat 3.5 – 4.5 GHzsmall CellHotspot 10 Gbps at28/39 GHzFuture mmwaveoptionsMostof the 3.5Ghz already awarded – Spectrum re arrangement to happen to Nokia 2017Ultrasmall Cell

5G Coverage Footprint – Combination of Low and High BandsLet’s make 3.7-4.2 GHz available5G mmwaves5G 3500mMIMOLTE-AWSLTE7005G6004 Nokia 20171000x localcapacity High bands for capacity Low band for IoT and lowlatency critical communication20 Gbps / 1000 MHz10x capacity withLTE grid withmassive MIMO2 Gbps / 100 MHzIoT and criticalcommunicationwith full coverage200 Mbps/ 10 MHz

5G Enhances Spectral UtilizationLTE 5x20 MHz100 MHz18 MHz18 MHz18 MHz5G 100 MHz100 MHzUp to 98 MHz5 Nokia 201718 MHz 18 MHz Wideband 5G carrier is more efficient thanmulticarrier LTE Faster load balancing Less common channel overhead No unnecessary guard bands betweencarriers. LTE uses 10% for guard bands.

5G Lean Carrier for Enhanced Efficiency Primary synchronization Secondary synchronization Broadcast channel LTE cell reference signalsLTE Cell specific reference signaltransmission 4x every millisecond Synchronization every 5 ms Broadcast every 10 msVery limited capability for base station power savings due tocontinuous transmission of cell reference signals5G20 ms5G enables advanced base station power savings6 Nokia 2017 No cell specific reference signals Synchronization every 20 ms Broadcast every 20 ms

Physical Channels & Physical SignalsPDSCHGNodeBDL shared channelPBCHPUSCHBroadcast channelUL shared channelPDCCHPUCCHDL control channelUL control channelPRACHDL Physical SignalsDemodulation Ref (DMRS)Phase-tracking Ref (PT-RS)Ch State Inf Ref (CSI-RS)Primary Sync (PSS)Secondary Sync (SSS)7 Nokia 2017Random access channelUL Physical SignalsUser EquipmentDemodulation Ref (DMRS)Phase-tracking Ref (PTRS)Sounding Ref (SRS)

Scalable NR NumerologyMacroCoverage15 kHz SCS NR supports scalablenumerology to addressdifferent spectrum,bandwidth, deployment andservices Sub-carrier spacing (SCS) of15, 30, 60, 120 kHz issupported for data channelsBW (e.g. 10, 20 MHz)MacroCoverage /Small Cell30 kHz SCSBW (e.g. 100 MHz)Indoor 60 kHz SCSBW (e.g. 200 MHz)mmWave120 kHz SCSBW (e.g. 400 MHz)8 Nokia 20172n scaling of SCS allows forefficient FFT processing

Flexible NR Framework NR provides flexibleframework to supportdifferent services and QoSrequirementsV2XFrequencyeMBBURL eMBBLCURL eMBBLCBLANKBLANK Scalable slot duration, minislot and slot aggregation Self-contained slotstructure Traffic preemption forURLLC Support for differentnumerologies for differentserviceseMBBBroadcastmMTC - eMTCeMBB eMBBNR transmission is wellcontained in time andfrequencymMTC – NB-IoTTime9 Nokia 2017 Future feature can beeasily accommodated

Scalable NR Slot Duration15 kHz SCS30 kHz 78Slot12910131112Slot60 kHz SCSSlotSlotSlotSlotSlotSlot120 kHz SCS One slot is comprised of 14 symbols Slot length depends on SCS – 1ms for 15 kHz SCS to 0.125ms for 120 kHz SCS Mini-slot (2,4, or 7 symbols) can be allocated for shorter transmissions Slots can also be aggregated for longer transmissions10 Nokia 2017SlotSlot13

NR frame/subframe DL only subframeUL only subframeDataControlDLDataDLControl(entirely DL or entirely UL)ULDMRSULCTRLSelf-contained subframeDLCTRL GPULDataULCTRLGPDL dataUL dataDL controlUL control0.125ms frame with cascadedUL/DL control signals (120 KHzSC)1.0 ms user plane latencyGP 011 Nokia 2017OFDM symbolGP0.125 msSame physical layer in UL and DLScalable Slot DurationFlexible UL/DLControl channel just before dataEnergy-effective processingGPTime

Initial AccessgNB periodically transmitssynchronization signalsand broadcast channelsSS Block #1gNB responds withRAR messageUE finds a good beam duringsynchronization, decodesMIB/SIB on that beamUE attempts random accesson the configured RACHresourceUE transmits Msg3 (e.g.RRC connection request)gNB responds withMsg4 (e.g. RRCconnection setup)gNB requestsbeam/CSI reportingUE responds with beam/CSIreportSS Block #NgNB switches beam12 Nokia 2017UE switches beam

SS Burst ExampleTime2395msSS burstSS burst230104PPPSBBSSCCSSHHSubcarrier numberSS burst periodicity5msSubcarrier numberFreqSS burst mapping to slots15 kHz (L 4)015 kHz (L 8)OFDMSymbol30 kHz (L 4)30 kHz (L 8)SS block120 kHz (L 64)240 kHz (L 64)Half frame (5ms)Slot with possible SS block(s)SS blocksTRP13 Nokia 2017

Overview of NR eMBB coding schemesLDPC Data channel BG1 and BG2 Quasi-cyclic (QC) Covers a wide range of codingrates and block sizes Full IR-HARQ support Benefits High throughput (paralleldecoding in hardware) Good performance14 Nokia 2017Polar codes Control channel DL: CRC-distributed polarcodes UL: CRC-aided and PC polarcodes Benefits Best performed short codes Low algorithmic complexity No error floor

What is “Massive MIMO”Massive MIMO is the extension oftraditional MIMO technology to antennaarrays having a large number ( 8) ofcontrollable antennasTransmission signals from the antennasare adaptable by the physical layer viagain or phase controlNot limited to a particularimplementation or TX/RX strategy15 Nokia 2017Enhance Coverage:High Gain Adaptive Beamforming Path Loss Limited ( 6GHz)Enhance Capacity:High Order Spatial Multiplexing Interference-limited ( 6GHz)

MIMO in 3GPP 16 Nokia 20175G / NRMassiveMIMO 32TX

Massive MIMO: Why logyCapability3GPP SpecSupportMost MacroNetworks willbecome congestedBelow 6GHz:desire to deployLTE/NR on sitegrids sized forlower carrierfrequenciesActive Antennasare becomingtechnically andcommerciallyfeasible3GPP supportsMassive MIMO inRel-13/14 for LTEand Rel-15 forNR/5GMassive MIMOrequires ActiveAntennatechnology3GPP-New-Radiowill be a “beambased” air interfaceSpectrum 3GHzand base sites willrun out of capacityby 202017 Nokia 2017Above 6GHz:Large Bandwidthsbut poor path lossconditions

Massive MIMO at Higher Carrier Frequencies ( 6 GHz)Poor path lossconditionsCost & powerconsumptionAntenna arrayimplementationBeam basedair interfaceLarge number ofantennas needed toovercome poorpath lossFull digital solutionsrequire transceiverunits behind allelementsSmaller formfactorsSingle sector-widebeam may notprovide adequatecoverageObtaining channelknowledge perelement is difficultWide bandwidths:A/D and D/Aconverters are verypower hungry18 Nokia 2017Distributed PAsolutions Hybrid arraysBeamforming at RFwith basebanddigital Precoding Beamform allchannels! Support analogand hybridarrays

NR-MIMO in the 3GPP New RadioMain Drivers of NR-MIMO DevelopmentDeployment Supportfrequencies bothbelow and above6GHzSupport both FDDand TDD19 Nokia 2017Scalable, Flexible ImplementationgNB: support full digital arrayarchitectures ( 6GHz) hybrid/analog architectures ( 6GHz), arbitrary TXRU configurations arbitrary array sizesUE: support traditional UE antennaconfigurations higher numbers of antennas UEs operating above 6GHz(hybrid/analog architectures)Purpose Enhance capacity(interferencelimiteddeployments)Enhance coverage(coveragechallengeddeployments)

Massive MIMO in 3GPP New Radio – Beam-based air-interfaceBeamformed Control ChannelsBeam ManagementCell 1Cell 2PSS2SSS2PCI2PSS1SSS1PCI1TRP1 (Cell1)TRP1 (Cell2)BRS#0BRS#0BRS#1BRS#1TRP2 (Cell1)PSS1SSS1PCI1BRS#2BRS#2BRS#3Beam ScanningBRS#3PSS2SSS2PCI2TRP2 (Cell2)Key features for beam-based AI20 Nokia 2017 Scalable and Flexible CSI Acquisition Framework High performing CSI Acquisition Codebooks Improved UL framework

Downlink MIMO Framework: Beam ManagementP-1UEP-2UE1 22314123TRP Initial gNB BeamAcquisition SSB or CSI-RS Nokia 201734TRP21UEP-3 gNB BeamRefinement E.g., CSI-RSTRP UE BeamRefinementForming beam ports for MIMO transmission (TX and RX)43

DL-MIMO Operation – Sub-6GHzSingle CSI-RS CSI-RS may or may not bebeamformedLeverage codebook feedbackAnalogous to LTE Class AProcess: gNB transmit CSI-RS UE computes RI/PMI/CQIMaximum of 32 ports in the CSI-RS(codebooks are defined for up to 32ports)Typically intended for arrays having32 TXRUs or less with no beamselection (no CRI)gNBMultiple CSI-RS Combines beam selection withcodebook feedback (multiplebeamformed CSI-RS with CRIfeedback)Analogous to LTE Class BProcess: gNB transmits one or moreCSI-RS, each in different“directions” UE computes CRI/PMI/CQISupports arrays having arbitrarynumber of TXRUsMax 32 ports per CSI-RSgNBUESRS-Based gNBCSI-RS (8 ports)CSI-RS (8 ports)Intended for exploiting TDDreciprocitySimilar to SRS-based operation inLTESupports arrays having an arbitrarynumber of TXRUs.Process: UE transmits SRS Base computes TX weightsSRSUECSI-RS (8 ports)RI/PMI(32)/CQICSI-RS (8 ports)RI/CQICRI/RI/PMI(8)/CQI22 Nokia 2017Disclaimer: NR-MIMO is flexible enough to support many variations on what is described on this slideUE

DL-MIMO Operation – Above 6GHzSingle Panel Array Combination of RF Beamforming and digitalprecoding at basebandRF Beamforming is typically 1RF BF weight vectorper polarization: a single “Cross-Pol Beam”2 TXRUs, Single User MIMO onlyBaseband Precoding Options: None (rank 2 all the time) CSI-RS based (RI/PMI/CQI) SRS-based (RI/CQI)23 Nokia 2017Multi-Panel Array Combination of RF beamforming and digital precoding atbasebandRF Beamforming is typically 1RF BF weight vector perpolarization per panel:One “Cross-Pol Beam” per sub-panelNumber of TXRUs 2 x # of panelsBaseband Precoding Options: CSI-RS based (RI/PMI/CQI) SRS-based (RI/CQI)SU- and MU-MIMO (typically one UE per Cross-Pol Beam)

CSI Framework: major componentsReport SettingsResource SettingsTrigger StatesWhat CSI to report and when to report itWhat signals to use to compute CSIAssociatesWhat CSI to report and when to report itwithWhat signals to use to compute the CSI Quantities to report:CSI-related or L1-RSRP-relatedTime-domain behavior: Aperiodic,semi-persistent, periodicFrequency-domain granularity:Reporting band, wideband, subbandTime-domain restrictionsfor channel and interferencemeasurementsCodebook configurationparametersType IType II24 Nokia 2017 A Resource Setting configures S 1CSI Resource SetsEach CSI Resource Set consists of:** CSI-RS Resources(Either NZP CSI-RS or CSI-IM)** SS/PBCH Block Resources(used for L1-RSRP computation)Time-domain behavior: aperiodic,periodic, semi-persistent** Periodicity and slot offsetNote: # of CSI-RS Resource Sets islimited to S 1 if CSI ResourceSetting is periodic or semipersistent. Links Report Settings withResource SettingsContains list of associated CSIReportConfig

Summary : UL MIMO Two transmit schemes are supported for NR uplink MIMO Codebook based transmission Up to 4Tx codebooks are defined for both DFT-S-OFDM and CP-OFDMNon-codebook based transmission UE Tx/Rx reciprocity based scheme to enable UE assisted precoder selection Diversity schemes are not explicitly supported in NR specification No diversity based transmission schemes are specified in Rel-15 NR UE can still use “transparent” diversity transmission scheme. 25 Nokia 2017UE may use 1Tx port procedure for specification-transparent diversity Tx schemes

Downlink Massive MIMO: NR vs LTE: 16 and 32 TXRUs, Full Buffer TrafficLTE:--Rel-13 Codebook 16 Ports and 32 Ports, Maximum Rank 8 (32 ports Rel-13 extension CB approved in Rel-14)Rel-14 codebook 16 Ports and 32 Ports, Maximum Rank 2NR:-NR Codebook Type I -16 Ports and 32 Ports, Maximum Rank 8NR Codebook Type II 16 Ports and 32 Ports, Maximum Rank 226 Nokia 2017

Gain of NR over LTE: 16 Ports – Full Buffer, 2GHz, DLCell EdgeMEAN2RX4RXUMi-200m27 Nokia 4RXUMa-750m Gain of NR over LTE is roughly 19-35% in Mean SE, 14%-30% in cell edge (Full Buffer) Gains in bursty traffic will be higher2RX4RXUMa-1500m

5x More2 – 4x–MoreEfficiency5G vs. 4G CapacityperSpectrumCell atwith2GHz16x4MIMO2GHzGHz2.6 GHz2GHz3.5 GHz20 MHz20MHz100 MHz20MHzMHz5.12 bps/Hz2 bps / Hzbps / Hz1.5 x 10-20 x 7.73 bps/Hz *102 Mbps cell-800 Mbpsthroughput5G 3500 withthroughput40 MbpsLTE2600withcell throughputmassive MIMObeamforming 2x2 MIMOLTE2GHz750m ISD16x4eNB (1,8,2) Nokia 2017155 Mbps cell400-800 Mbpsthroughputcell throughput In Full Buffer, NR Codebooks showsignificant gains over LTE Codebooks- Mean UE throughput: 26%- Cell edge: 25%284-8 bps / Hz5G 3500 withNRmassive MIMObeamforming2GHz750m ISD16x4gNB (1,8,2)* Includes 20%improvement due tolean carrier in NR

Uplink Performance: 32 Rx – Full Buffer, 2GHzISD200m, 500m, 750m0.500.450.400