1、The way to 5Gtechnology framework aspectsReiner Stuhlfauth5SWT,Technology Marketing Manager5GWhat can be expected22010l LTE/LTE-A gradual evolution will not be sufficient,if the number of devices(M2M)and data consumption will increase as forecasted and if latency needs to be reduced significantly.l
2、Obvious that higher bandwidth and higher frequencies will play a rolel Potential new air interface(s),which would also allow to satisfy tight latency requirementsl Integration of potential disruptive technologies with LTE/LTE-A(2G/3G/WLAN)will be key!LTE R12/13LTE R10/11LTE R8/9201320152020“Horizon2
3、020”Potential New AdapRtiAvTe NewRAT+LTE R14/15LTE R14/155G Standardization33GPP 5GWorkshopChannel modeling 6 GHzRelease 15Rel-16ITU IMT-2020SubmissionRelease 16Release 145G Work Items Phase 2Release 135G Scope and Requirements5G Phase 2Specification3GPP 5G Standardization Schedule201520162017201820
4、1920205G Work Items Phase 15G Phase 1Specification5G Study Items(Evaluation of Solutions)LTE Advanced EvolutionHigher frequencies,timeline from ITUMobile Data Traffic Growth and TrendsMobile Video/Global Forecast by Region Mobile video will grow at a CAGR of 69 percent between 2013 and 2018 Mobile v
5、ideo will generate 69.1%of the mobile traffic by 2018 Asia Pacific and North America account for 61%of mobile traffic by 2018Ref:CISCO VNI mobile 2014Vision:2000:1 billion connected places 2010:5 billion connected people 2020:50 billion connected things5Way to 5G variety in user applicationsTraffic
6、variety but also QoS and characteristics variety,e.g.sporadic versus streaming,low data vs.high data,background vs.short latency,etc.6Outlook:New applications and services with specific&diverse communication requirementsSafety Critical ServicesReal-time Media ApplicationsMission Critical ServicesInt
7、ernet of EverythingEvolution of LTE/LTE-A is not sufficient to satisfy future requirements7IMT 2020-serviceseMBBuMTCmMTC20.11.20159Worldwide Research Activities and InitiativesOverview(chronological order)NYU Wireless:US research center conducting massive work on propagation characterizationat mm-wa
8、ve frequencies since 2012 5GNOW:Non Orthogonal Waveforms(started in Sept 2012)METIS:Mobile and wireless communications Enablers for the Twenty-twenty Information Society(started in Nov 2012)MiWEBA Millimetre-Wave Evolution for Backhaul and Access(June 2013)IMT-2020/Future Forum*:China 5G organizatio
9、ns(Feb 2013)5G Forum*:Korean industry-academy-R&D cooperation system established in May 2013 2020 and Beyond Adhoc:In Japan ARIB established a new AdHoc working group in Sep 2013 5G Innovation Centre*:5G research in the UK started in Nov 2013 Horizon 2020:EU Research and Innovation program(2014-2020
10、)NGMN 5G Initiative*(started at MWC 2014)5G Lab Germany*(TU Dresden,opened in Sept 2014)10*R&S is member/activeUse cases:Much more than only Mobile BroadbandScenarios&Requirements Mobile broadband/Dense crowd of users:Mobility,high data rates,high capacity and partly limited area.Internet of Things(
11、emergency comms,robots,):Low latency,high reliability,resilience and security;user case specificdata rates/capacity.Internet of Things(sensors;leisure applications,):The volume of devices and“things”will create new requirements.Battery life time expectation years11Picture:ETH Zrich/Golem.deVery high
12、 data rateLong battery lifetimeMobilityMassive number of devicesReliability,resilience,securityVery low latencyVery high capacityMobile broadbandDense crowd of usersIoT sensor networkIoT control networkEvolution of LTE-5GNew scenarios:Broadcast+Multicast,device to device,M2MNetwork densification:Het
13、erogeneous networks,dual link radioDevice enhancements:Enhanced receiver,long standby timeSpectrum flexibilityAdditional frequencies,carrier aggregationMulti-RAT coordinationWLAN offloading,enhanced dual linkMulti Antenna techniquesEnhanced MIMO,beamforming,CoMPRel.12Rel.10Rel.1212LTERel.8From Link
14、Efficiency to System EfficiencyLink EfficiencySystem EfficiencyLegacyfocusFuturefocusOne RAT:link adaptation with coding+modulation to send as much data as possibleSystem adaptation,to select the RAT that offers the best data transmission according tothe requested quality of service for each service
15、13Neighbor cellSynchronisation and orthogonalityPhysical cell IDPhysical cell IDServing cellUE synchronizes toserving cellRessource allocation isorthogonal to other UEsNew connection situations require a re-thinking of sync+orthogonality:long standby time,MTC,heterogeneous network structures,various
16、 connection rates,simplicity of handling+re-thinking mobility aspects14New types of trafficTactile Internet High data rate and lowlatency for videos,Internet of Things(M2M)Sporadic asynchronous Machine TypeCommunications(MTC)with medium latency and energy-efficient costsSource:5GNOW,“Unified Frame S
17、tructure and Waveforms for 5G”New types of trafficClassic type:Bit pipe.Like mobile communication today:synchronisation aspects,orthogonality and scheduling rulesMETIS:Type 1,bit pipeScheduled RAT usage.Orthogonality+synchronisation neededNew types of trafficLayerd type:Bit stream is sent over sever
18、al radio link layers,even up to severalRATs.E.g.LTE and WLAN offloading or macro+pico cell in conjunction00 11 01 10 01 01 11 01.METIS:Type 2,layered bit pipeCommon buffer+dispatcherScheduled RAT usage.Complex scheduling over multiple RATsOrthogonality+synchronisation neededNew types of trafficMETIS
19、:Type 3,Machine type communication MTCMTC type:Very low latency!E.g.machine type communication or device to deviceNot necessarily full scheduling.Orthogonality+synchronisationMay not be given.Sporadic channel access,bursted trafficMulti-hop communication,ODMA:opportunity driven multiple accessNew ty
20、pes of trafficMETIS:Type 4,Sensor like communicationSensor like type:Very energie efficient!E.g.machine type communication or multi-hop.Not necessarily full scheduling.Orthogonality+synchronisation may not be given.Sporadicchannel access,bursted traffic.Long standby time,low data rate.Energy efficie
21、nt sensor like communication.Cognitive radio.e.g.Fire detectorsCognitive radio:sporadic access+spectrum efficiencyCognitive radios intelligently exploits available side information about the(a)Channel conditions(b)Activity(c)Codebooks(d)Messagesof other nodes with which they share the spectrum20Air
22、interface framework for 5GDuplexmethod FDD TDD Flexible duplex Full duplexWave-formsMultipleantennaMultipleaccessModulationcodingProtocolaspects High+low frequencies OFDMA Singlecarrier FBMC UFMC GFDM F-OFDM Massive MIMO Beamforming Centralized Distributed NxN MIMO OFDMA SCMA NOMA PDMA MUSA IDMA Pol
23、ar codes LDPC APSK Network coding Turbo codes FTN Split C/U plane AdaptiveHARQ Grant free access Low energy modeVarious combinations of above methods to fulfill multiple scenarios21Technology framework:Infrastructure trends22Heterogeneous networks:capacity increaseCloud based RAN:traffic analysisCen
24、tralized RANActive Antenna Systems(AAS)Fiber to the antennaBBUTechnology framework:5G Spectrum Outlook23f GHz6070809001020304050Available spectrumHigh bandwidth is only possible at high frequenciesLink BudgetAdditional spectrum:470 694:226 MHz694 790:96 MHz1300 1700:400 MHz2025 2100:85 MHz2200 2290:
25、80 MHz2700 3400:700 MHz3400 5000:1600 MHz5350 5470:120 MHz5850 6425:575 MHzUsed spectrum:700-900:20 100 MHz 1500/1600:40 70 MHz 1800/1900:120 MHz 2100:120 MHz 2300:100 MHz 2600:140 MHz 3600:200 MHzAdditional spectrum:Chunks of 3 7 GHz!wirelesspersonal networks WPAN using optical link In particular l
26、ow latency requirements require redesign Many different use cases suggest more than a single air interface Discussed candidates comprise:UFMC:Universal Filtered Multi-CarrierFBMC:Filter-Bank Multi-CarrierGFDM:Generalized Frequency Division MultiplexingF-OFDM:Filtered/Flexible OFDM Common advantages
27、at the cost of higher complexity:Better robustness against imperfect synchronismReduced out-of-band emission24Technology framework:New waveform candidatesreduced out of band emissionstimeIdeal:waveform is fully orthogonal in time&frequency.No inter carrier interference ICI&well known localization in
28、 time&frequency But:reality is different(real world channel conditions)!no need to be synchronized+better spectral efficiency In the end the question“What is the best waveform for 5G”is not easy to answer It is a question of which scenarios are prioritized.Idea is:requested service will define which
29、 air interface candidate-possibly coexistence of various air interface waveformsLAD2DWireless BHOutdoor(outdoor)Macro/wide area High prop.delayv 50km/h doubly dispersive channelMTC/MMCMulti-site CoMP asynchronous access coexistence with other systems Short block lengthNew spectrum Higher frequencies
30、/cognitive radioMicro/small cell High throughputTechnology framework:New waveform candidates25Separation of control+user planeTechnology framework:Protocol aspects/targets Multiple radio connections in parallel Reduce signalingMesh networks:multihop and device to deviceSR/PUCCHUL Grant/PDCCHDATA/PUS
31、CH Grant free accessMultiplexing.Scheduling/Priority HandlingTransport ChannelsMACRLCPDCPSegm.ARQ etcSegm.ARQ etcLogical ChannelsROHCROHCRadio BearersSecuritySecurityHARQHARQ.CC1.CCx Light MAC and RRMfor energy saving modes26UplinkGuard bandTxDownlinkRxDown-and UplinkfrequencyRxTxtimeDuplex=how to s
32、eparate Rx and Tx?Technology framework:Duplex methodsDSUUUDSUUUDSUDDDDDDDThe classics:FDD(guard band)and TDD(guard time)The flexible:HetNet with flexible duplexThe future outlook:Full duplex to obtain higher Capacity(at costs of higher complexity)2728Example:in QAM there aremultiple amplitude values
33、 dynamic range of power amplifer+Crest factorFilter edges may curtail the constellationof the QAM symbolsTechnology framework:Modulation&CodingCompare toe.g.12+4 PSK less amplitude valuesInter-symbol Interference free in time,Pulses fulfillNyquist criterion.Pulses are no longer orthogonal.+1-1+1-1-1
34、+1-1+1-1-1Time gainTechnology framework:Modulation&CodingCoding trends:low complexity energy efficient fast decoding high data rate hardware implementation low latencyBut:there is no code supporting all the requests it looks like multiple codes will coexist depending on the service:LDPC codes,Turbo
35、codes;Polar codes etc.Pulses are no longer orthogonal,faster symbol rate Receiver has to remove ISI!Faster than Nyquist idea to shorten pulse length and send more data per spectrum2930Requirements for connection density in 5G:-ideas to enhance spectrum efficiency,but there wont be any complete new m
36、ultiple access!-it will be more like a superposition:codes+frequency channels,e.g.CDMA+OFDMA Space division multiple access and beamformingN SC B T log 21Shannons law isstill validTechnology framework:Multiple access schemesCurrent discussions to achieve 10 times capacity improvements1+C=logGoal is
37、to increase the capacityUltra dense Networks,Small cells+massiveMIMO/beamformingNxN MIMOWider bandwidthFind known“signals andapply interferencecancellation methodsreduce“noise dueto better coding&modulation schemes31Send NULLs in this directionCoordination of pencil beams to steer desired direction&
38、place NULLs in interfering“directionsSDMA=Space division multiple accessTechnology framework:Multiple access schemesBasic idea is to overlap OFDMA subcarrier principle with code division multiple access One subcarrier may contain traffic ofmultiple usersUser 1User 2Signal specific filteringDecoding
39、of user 1 signalSignal specific filteringSIC,selective interference cancellation of user 1 signalDecoding of user 2 signalNOMA32Massive MIMO/mm-Wave MIMO33Beamforming is one important aspect Massive MIMO characterized byVery large(i.e.number of Tx elements)antenna array at the base station.Large num
40、ber of users served simultaneously(choosingthe right group of antenna elements for the specific users)TDD allows channel estimation without UE feedback.Leveraging the multiplicity of(uncorrelated)propagation channels to achieve high throughput.mm-Wave MIMO/beamforming characterized byVery small(in t
41、erms of dimensions)antenna arrays possibleHighly directional transmission is needed tocompensate severe path loss(beamformingused at Tx and Rx)Dynamic beam adaptation is essentialOver the air measurements will become much more importantDynamic beamforming verification requires enhancement of the exi
42、sting test proceduresTodays situation+future splitOutdoor cellToday:one common RAT for all access scenarios:indoor,outdoor.High velocity,large and small cells,Outdoor cellFuture:various RATs for various access scenarios:indoor,outdoor,low+high velocity,large and small cell sitesi.e.low mobility,high
43、 data ratei.e.high mobility,large cell sizei.e.machine type,long standby time345G Spectrum OutlookHigh bandwidth is only possible at high frequenciesf GHzE bandV band6070809001020304050W bandAvailable spectrumLink BudgetAdditional spectrum:470 694:694 790:1300 1700:2025 2100:2200 2290:2700 3400:3400
44、 5000:5350 5470:5850 6425:226 MHz96 MHz400 MHz85 MHz80 MHz700 MHz1600 MHz120 MHz575 MHzUsed spectrum:700-900:1500/1600:1800/1900:2100:2300:2600:20 100 MHz 40 70 MHz 120 MHz 120 MHz 100 MHz 140 MHzAdditional spectrum:Junks of 3 7 GHz!freq.upconverterGeneral considerations and challenges of high frequ
45、ency test setupsmm-wave reference plane,DUT is inserted hereLOIF36GeneratorGeneratorfreq.down converterLOGeneratorScope/Analyzer(SW)RFSignal GenerationSignal AnalysisIFComplexity of the test setup is very high(many instruments,up-and down-conversion,etc.)Be careful with signal quality and the perfor
46、mance of used test instruments!Be careful with increasing sensitivity of mm-wave test setups(touching cables,handlingwaveguides,etc.)repeatability should be key!Try to simplify the setup as much as possible(avoid up-and down-conversion)Principles of Up-convertersmm-wave Up-Converter(example)fIFfLO4x
47、Typical Up-converter components:Frequency multiplier(for Local Oscillator frequency,4x or 6x or)(e.g.a 4x frequency multiplier costs 12dB phase noise;a 6x multiplier 15.5dB)MixerBand pass filters(for image suppression)Power Amplifier(to reach a suitable signal level)Up-Converters are frequency speci
48、fic(components need qualification)What is the impact on signal quality?Up-Converter Challenges38Frequency0FIFFLOFRF=FLO+FIFFimage=FLO-FIF Filtering is necessary during the up-conversion processMixing process results in image of the wanted signalBand pass filterSingle side band phase noise Multiplyin
49、g the frequency of a signal by a factor of N using an ideal frequency multiplier increases the phase noise of the multiplied signal by 20log(N)dB.Channel soundingMain idea of channel sounding is to understand the wave propagation characteristics Like attenuation,power delay profile,direction of arri
50、val,correlation aspects etc.-especially for the higher“frequency rangesChannel sounding multipath propagation MPPTxiiij t L1i0 h ,t a t eChannel impulse response CIRdelay spread|h|Minimum measurement durationSeparatibility of MPP components Identify each MPP component.1 path delaypath attenuationpat
