Receiver Design for High Spectral Efficiency Communication Systems in Beyond 5G

157 Pages·2023·2.876 MB·English

by  Weijie Yuan, Nan Wu, Jingming Kuang

Weijie Yuan
Nan Wu
Jingming Kuang
Receiver Design
for High Spectral
Efficiency
Communication
Systems in Beyond
5G
Receiver Design for High Spectral Efficiency
Communication Systems in Beyond 5G
· ·
Weijie Yuan Nan Wu Jingming Kuang
Receiver Design for High
Spectral Efficiency
Communication Systems
in Beyond 5G
WeijieYuan NanWu
DepartmentofElectronicandElectrical SchoolofInformationandElectronics
Engineering BeijingInstituteofTechnology
SouthernUniversityofScience Beijing,China
andTechnology
Shenzhen,Guangdong,China
JingmingKuang
BeijingInstituteofTechnology
Beijing,China
ISBN 978-981-19-8089-3 ISBN 978-981-19-8090-9 (eBook)
https://doi.org/10.1007/978-981-19-8090-9
©TheEditor(s)(ifapplicable)andTheAuthor(s),underexclusivelicensetoSpringerNature
SingaporePteLtd.2023
Thisworkissubjecttocopyright.AllrightsaresolelyandexclusivelylicensedbythePublisher,whether
thewholeorpartofthematerialisconcerned,specificallytherightsoftranslation,reprinting,reuse
ofillustrations,recitation,broadcasting,reproductiononmicrofilmsorinanyotherphysicalway,and
transmissionorinformationstorageandretrieval,electronicadaptation,computersoftware,orbysimilar
ordissimilarmethodologynowknownorhereafterdeveloped.
Theuseofgeneraldescriptivenames,registerednames,trademarks,servicemarks,etc.inthispublication
doesnotimply,evenintheabsenceofaspecificstatement,thatsuchnamesareexemptfromtherelevant
protectivelawsandregulationsandthereforefreeforgeneraluse.
Thepublisher,theauthors,andtheeditorsaresafetoassumethattheadviceandinformationinthisbook
arebelievedtobetrueandaccurateatthedateofpublication.Neitherthepublishernortheauthorsor
theeditorsgiveawarranty,expressedorimplied,withrespecttothematerialcontainedhereinorforany
errorsoromissionsthatmayhavebeenmade.Thepublisherremainsneutralwithregardtojurisdictional
claimsinpublishedmapsandinstitutionalaffiliations.
ThisSpringerimprintispublishedbytheregisteredcompanySpringerNatureSingaporePteLtd.
The registered company address is: 152 Beach Road, #21-01/04 Gateway East, Singapore 189721,
Singapore
Foreword
Thisresearchmonographaddressesonethemostpressingissuesofwirelesscommu-
nications, namely the avoidance of the impending ‘spectrum crunch’. In the early
eraofwirelesscommunicationsonlythepoliceandmilitaryaswellastherichand
famoushavehadaccesstomobiletelephony,whichresultedinratherlimitedtele-
traffic.Hencehavinghighspectralefficiencywasmuchlesscriticalthanintheera
atthetimeofwriting,whenlow-costcommercialdevicesarereadilyavailabletothe
generalpublic.
The first digital mobile radio system supporting international roaming was the
Global System of Mobile communications known as GSM, which was designed
andstandardizedduringthelate1980sbytheEuropeanUnionandspreadtomore
than150countriesacrosstheglobe.Inthisearlyeraitadoptedthethenextremely
radical design principle of using a partial response modulation scheme referred to
as Gaussian Minimum Shift Keying (GMSK). The benefit of this partial response
scheme is that each modulating symbol’s effect is spread across multiple symbol
intervals, which hence facilitates having very smooth, slowly evolving modulated
waveforms. When combined with signaling relying on Gaussian shaping of the
waveform,itresultsinthemostcompactspectral-domainrepresentationthatmaybe
attained.Thisishoweverachievedatthecostofconsciouslyintroducingconrolled
intersymbol interference, which necessitates the employment of channel equaliza-
tion even in the absence of any channel-induced Intersymbol Interference (ISI) or
MultiuserInterference(MUI).
By contrast, the Third-Generation (3G) wireless systems opted for the employ-
ment of Code Division Multiple Access (CDMA) relying on so-called Orthog-
onal Variable Spreading Factor (OVSF) codes and a total bandwidth of 5 MHz,
whichresultedinfrequency-selectedfadingintypicalcellularscenariosandhence
sufferedfromthedeleteriouseffectsofdispersionthatrequiredsophisticatedreceiver
techniques. This realization triggered a spate of research activities on the concep-
tionofmorebandwidth-efficientnon-orthogonalCDMAandawholehostofother
non-orthogonalsignalingsolutions.
Thistimelyresearch-orientedbookfollowsasimilarlineofinvestigationinthe
emerging 6G era. The rationale is that with the advent of Moore’s Law a whole
v
vi Foreword
suiteofsophisticatedreceivertechniquesareavailableformitigatingthedeleterious
effectsofISIandMUI.HencethebenefitsofFaster-than-Nyquist(FTN)signaling
are quantified in the presence of radically new receivers. Furthermore, the merits
of Sparse Code Multiple Access (SCMA) are discussed, which is also eminently
suitable for grant-free access in support of transmitting short messages from IoT
nodesforexample,withtheobjectiveofavoidingtheexcessivehandshakingdelays
ofIoTsystems.
Wishingyouintellectualstimulationandfun,whileconsultingthebook.
October2022 LajosHanzo
ChairofTelecommunications
UniversityofSouthampton
Southampton,UK
Preface
Withtherapiddevelopment ofmodernsociety,peoplehaveanincreasingdemand
for higher data rates. Due to the limited available bandwidth, how to improve the
spectral efficiency becomes a key issue in the beyond 5G mobile communication
system. Recent researches show that by introducing non-orthogonalties, the non-
orthogonalsystemiscapableoftransmittingmoreinformationandsupportingmore
userswithinthesameresourceelements,leadingtoimprovedspectralefficiency.In
general,thehighspectralefficiencycommunicationsystemcanbeachievedbyusing
Faster-Than-Nyquist(FTN)signalingwhichbreakstheNyquistcriteriontotransmit
moredatasymbolsinthesametimeperiod.Anothersolutionistomultiplexmore
usersovertheorthogonalresourceelementstoprovidewirelessconnectivitytomore
users,whichisknownasNon-orthogonalMultipleAccess(NOMA).Amongseveral
NOMAtechnologies,thecodedomainNOMA,e.g.,SparseCodeMultipleAccess
(SCMA)couldachievefurthershapinggain.Nevertheless,FTNsignalingwillresult
in intersymbol interference (ISI) while NOMA system will introduce interference
betweendifferentusersusingthesameresourceelements,leadingtochallengeson
receiverdesign.Thisbookfocusesonthereceiverdesignforhighspectralefficiency
communication systems in beyond 5G era. We summarize the main innovations
containedinthisbookasfollows:
Chapter2presentsanenergyminimization-basedSCMAdecodingalgorithmfor
uplinksystem.Relyingontheoptimizationtheoryandvariationalfreeenergy(VFE)
framework,theaposterioridistributionofeachtransmitteddatasymbolisderived.
Then,theconvergencebehavioroftheproposedalgorithmisfurtheranalyzed,which
provestheconvergenceoftheaposteriorivarianceofthedatasymbol.
Chapter3developsalow-complexityreceiverrelyingonareconstructedstretched
factorgraphfordownlinkMIMO-SCMAsystem.Toaddresstheconvergenceissueof
thecurrentMPA-baedreceiverontheloopyfactorgraph,aconvergenceguaranteed
messagepassingreceiverisproposedbyconvexifyingtheBethefreeenergy.Finally,
cooperative detection schemes that allow the downlink users to share information
areproposedtoachievediversitygain.
In Chap. 4, we solve the problem of FTN signaling detection over frequency
selectivechannelswithunknownchannelknowledge.Insteadofthecommonlyused
vii
viii Preface
compositeISIchannel model,weintentionallyseparatetheknownISIinduced by
FTN and the unknown ISI introduced by channel fading, which results in better
detectionperformanceandreducedcomplexity.
InChap.5,FTNtransmissionoverdoublyselectivechannelsisconsidered.Two
low-complexity receiver designs, namely Gaussian message passing (GMP)-based
andvariationalinference-basedmethodsareproposed.Inparticular,bothmeanfield
andBetheapproximationsareconsideredandcomparedintermsofdetectionperfor-
mance and complexity. The GMP-based scheme is then extended to an imperfect
channelcase.
Chapter6studiesanovelnon-orthogonalcommunicationsystembyintegrating
FTNsignalingintoSCMAsystem,whichleadstoanevenhigherspectralefficiency.
To eliminate the ISI and inter-user interference (IUI), a low-complexity receiver
is designed based on the factor graph framework for joint channel estimation and
SCMAdecoding.Then,consideringthegrant-freetransmission,thefactorgraphis
modifiedbyincludingtheuseractivitydetection.
Chapter7ofthisbookinvestigatesageneralFTN-NOMAsystemwithrandom
accessinpracticaldynamicenvironments.Jointuseractivitytracking,channelesti-
mation,anddatadetectionaredonebynovelexpectationmaximization(EM)-MPA
receiveriteratively.Allmessagesandbeliefsofunknownvariablesaredetermined
inparametricforms,resultinginlow-complexitysignalreception.
Finally, Chap. 8 summarizes this book by emphasizing the innovative results.
Then,weprovideseveralfutureresearchdirectionsforfurtherinvestigation.
Ourhopeisthatthisbookwouldprovideagoodreferencefortheresearchersin
theareaofiterativereceiver designforsupportingnewcommunication systemsin
the era of beyond 5G. This book can also be used as a textbook for postgraduate
courses.
The authors would like to express their sincere thanks to the people who have
helped the accomplishment of this book: Lajos Hanzo, Yonghui Li, Hua Wang,
XiaojingHuang,AndrewZhang,QinghuaGuo,JinhongYuan,DerrickWingKwan
Ng, Chengwen Xing, and Chaoxing Yan. The authors also want to thank Hongjia,
Zhongjie, Xiaoqi, Jun, Buyi, Xinyuan, Xiang, and Kecheng for helping edit the
figures in this book. In the end, the author Weijie Yuan would thank Ms. Jasmine
Zhangforhercompanyandsupport.
Shenzhen,China WeijieYuan
August2022 NanWu
JingmingKuang
Contents
1 Introduction of High Spectral Efficiency Communication
Systems ....................................................... 1
1.1 Background ............................................... 1
1.2 Faster-Than-NyquistSignaling ............................... 3
1.3 SparseCodeMultipleAccess ................................ 7
1.4 TheObjectives ............................................. 10
2 UplinkMulti-userDetectionforSCMASystem ................... 13
2.1 Introduction ............................................... 13
2.2 SystemModel ............................................. 14
2.3 Low-ComplexityReceiverDesign ............................ 15
2.3.1 BayesianInference-BasedApproach .................... 15
2.3.2 ComputationalComplexity ............................ 19
2.4 ConvergenceAnalysis ....................................... 20
2.5 SimulationResults .......................................... 24
2.6 Conclusions ............................................... 26
3 DownlinkMulti-userDetectionforMIMO-SCMASystem ......... 29
3.1 Introduction ............................................... 29
3.2 MIMO-SCMAModel ....................................... 30
3.2.1 ProbabilisticModel .................................. 31
3.3 Stretched Factor Graph and Low-Complexity Message
PassingReceiver ........................................... 32
3.3.1 FactorGraphRepresentation ........................... 32
3.3.2 MessagePassingonStretchedFactorGraph ............. 32
3.3.3 AlgorithmSummary .................................. 37
3.4 Convergence-GuaranteedMessagePassingReceiver ............. 37
3.4.1 VFEandBeliefPropagation ........................... 37
3.4.2 Convergence-GuaranteedBP-EPReceiver ............... 40
3.4.3 ComplexityAnalysis ................................. 44
3.5 DistributedCooperativeDetection ............................ 45
3.5.1 BeliefConsensus-BasedMethod ....................... 46
ix
x Contents
3.5.2 BregmanADMM-BasedMethod ....................... 47
3.5.3 AlgorithmSummary .................................. 50
3.6 SimulationResults .......................................... 51
3.7 Conclusions ............................................... 56
4 FTNDataDetectionandChannelEstimationoverFrequency
SelectiveChannels .............................................. 59
4.1 Introduction ............................................... 59
4.2 FTNSignalingModel ....................................... 60
4.3 Low-ComplexityMessagePassingReceiverDesign ............. 62
4.3.1 Forney-StyleFactorGraphRepresentation ............... 63
4.3.2 GaussianMessagePassingAlgorithm ................... 65
4.3.3 ComputationofExtrinsicLLR ......................... 69
4.3.4 ComplexityAnalysis ................................. 70
4.4 SimulationResults .......................................... 71
4.5 Conclusions ............................................... 75
5 Receiver Design for FTN Signaling over Doubly Selective
Channels ...................................................... 77
5.1 Introduction ............................................... 77
5.2 SystemModel ............................................. 78
5.2.1 FDE-MMSEBasedAlgorithm ......................... 79
5.3 VFE-BasedReceiverDesign ................................. 79
5.3.1 VFE-BasedMethod .................................. 80
5.3.2 ComplexityReduction ................................ 83
5.3.3 SimulationResults ................................... 84
5.4 GMP-BasedReceiverDesign ................................ 85
5.4.1 GMP-BasedMethod .................................. 86
5.4.2 ImperfectChannelInformation ........................ 88
5.4.3 SimulationResults ................................... 89
5.5 Conclusions ............................................... 91
6 ReceiverDesignforFTN-SCMACommunicationSystem .......... 93
6.1 Introduction ............................................... 93
6.2 SystemModel ............................................. 94
6.3 ReceiverDesignforFTN-SCMASystems ..................... 96
6.3.1 ApproximationofColoredNoise ....................... 96
6.3.2 ProbabilisticModelandFactorGraphRepresentation ..... 96
6.3.3 MessagePassingReceiverDesign ...................... 98
6.4 UserActivityDetectioninGrant-FreeSystem .................. 101
6.4.1 Probability-BasedActiveUserDetection ................ 101
6.4.2 Message Passing Based Active User Detection
Algorithm ........................................... 103
6.5 SimulationResults .......................................... 107
6.6 Conclusions ............................................... 113