ETSI GR RIS -Reconfigurable Intelligent Surfaces (RIS) -Use Cases,Deployment Scenarios and Requirements-此为英文文档

ETSIGRRIS001V1.1.1(2023-04)

GROUPREPORT

ReconfigurableIntelligentSurfaces(RIS);

UseCases,DeploymentScenariosandRequirements

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2ETSIGRRIS001V1.1.1(2023-04)

Reference

DGR/RIS-001

Keywords

3GPP,architecture,MIMO,radio

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3ETSIGRRIS001V1.1.1(2023-04)

Contents

IntellectualPropertyRights

5

Foreword

5

Modalverbsterminology

5

1Scope

6

2References

6

2.1

Normativereferences 6

2.2

Informativereferences 6

3Definitionofterms,symbolsandabbreviations

6

3.1

Terms 6

3.2

Symbols 6

3.3

Abbreviations 6

4Definition

7

4.0

RISdefinition 7

4.1

Structure 8

4.1.0

Generaloverview 8

4.1.1

Metamaterials 8

4.1.2

Reflectarray 8

4.2

Hardwaredesign 9

4.2.0

Typesofhardwaredesign 9

4.2.1

ActiveRIS 9

4.2.2

PassiveRIS 9

4.2.3

HybridRIS 9

4.3

Operatingmode 10

4.3.1

Reflectionmode 10

4.3.2

Refractionmode 10

4.3.3

Absorptionmode 10

4.3.4

Backscatteringmode 10

4.3.5

Transmittingmode 11

4.3.6

Receivingmode 11

4.4

Operatingfrequency 11

4.4.0

Description 11

4.4.1

RISbandwidthofinfluence 12

4.4.2

Sub-6GHzband(FR1) 12

4.4.3

mmWaveband(FR2) 12

4.4.4

Terahertzband 12

4.4.5

Unlicensedbands 13

4.5

Communicationduplexmode 13

4.5.1

TDD 13

4.5.2

FDD 14

4.5.3

Fullduplex 14

5

Descriptionofusecases 15

5.0

Generaldescription 15

5.1

Coverageenhancement 15

5.2

Spectralefficiency 17

5.3

Beammanagement 18

5.4

Physicallayersecurity 18

5.5

Localizationaccuracy 19

5.6Sensingcapabilitie

s 19

5.7

Energyefficiency 19

5.7.1

Wirelesspowertransfer 19

5.7.2

Energyharvesting 20

5.7.3

Powersaving 20

5.7.4

EMFexposureminimization 20

5.8

LinkManagement 21

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4ETSIGRRIS001V1.1.1(2023-04)

5.8.1

ProgrammableWirelessDataCenters 21

6

Deploymentscenarios 21

6.0

Generaldescription 21

6.1

Operatingenvironment 22

6.1.1

Indoorscenarios 22

6.1.2

Outdoorscenarios 22

6.1.3

Hybridscenarios 22

6.2

RISdeployment 22

6.2.1

StaticRIS 22

6.2.2

NomadicRIS 22

Description 22

PersonalRISscenario 23

UE-integratedRISscenario 23

Vehicle-integratedRISscenario 23

6.3

RIScontrolplane 23

6.3.0

Description 23

6.3.1

Centralizedmanagement 24

6.3.2

Distributedmanagement 24

6.3.3

AutonomousRIS 24

6.3.4

UE-controlledRIS 25

7

Requirements 25

7.1

HardwareCost 25

7.2

EaseofDeploymentandMaintenance 26

7.3

SignalPowerBoosting 26

7.4

Reconfigurability 26

7.5

Interoperability 27

7.6

Regulatoryrequirements 28

History 29

ETSI

5ETSIGRRIS001V1.1.1(2023-04)

IntellectualPropertyRights

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Trademarks

Thepresentdocumentmayincludetrademarksand/ortradenameswhichareassertedand/orregisteredbytheirowners.ETSIclaimsnoownershipoftheseexceptforanywhichareindicatedasbeingthepropertyofETSI,andconveysnorighttouseorreproduceanytrademarkand/ortradename.MentionofthosetrademarksinthepresentdocumentdoesnotconstituteanendorsementbyETSIofproducts,servicesororganizationsassociatedwiththosetrademarks.

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Foreword

ThisGroupReport(GR)hasbeenproducedbyETSIIndustrySpecificationGroup(ISG)ReconfigurableIntelligentSurfaces(RIS).

Modalverbsterminology

Inthepresentdocument"should","shouldnot","may","neednot","will","willnot","can"and"cannot"aretobeinterpretedasdescribedinclause3.2ofthe

ETSIDraftingRules

(Verbalformsfortheexpressionofprovisions).

"must"and"mustnot"areNOTallowedinETSIdeliverablesexceptwhenusedindirectcitation.

ETSI

6ETSIGRRIS001V1.1.1(2023-04)

1Scope

ThepresentdocumentidentifiesReconfigurableIntelligentSurfaces(RIS)relevantusecaseswithcorresponding

generalKeyPerformanceIndicators(KPIs),deploymentscenariosoperationalrequirementsforeachidentifiedusecase.KPIsandoperationalrequirementswillincludesystem/linkperformance,spectrum,co-existence,andsecurity.

2References

2.1Normativereferences

Normativereferencesarenotapplicableinthepresentdocument.

2.2Informativereferences

Referencesareeitherspecific(identifiedbydateofpublicationand/oreditionnumberorversionnumber)or

non-specific.Forspecificreferences,onlythecitedversionapplies.Fornon-specificreferences,thelatestversionofthereferenceddocument(includinganyamendments)applies.

NOTE:Whileanyhyperlinksincludedinthisclausewerevalidatthetimeofpublication,ETSIcannotguarantee

theirlong-termvalidity.

Thefollowingreferenceddocumentsarenotnecessaryfortheapplicationofthepresentdocument,buttheyassisttheuserwithregardtoaparticularsubjectarea.

[i.1]3GPPTR22.858(V18.2.0):"Studyofenhancementsforresidential5G(Release18)".

[i.2]3GPPTR22.859(V18.2.0):"StudyonPersonalInternetofThings(PIoT)networks(Release18)".

[i.3]3GPPTS38.104(V18.0.0):"NR;BaseStation(BS)radiotransmissionandreception

(Release18)".

3Definitionofterms,symbolsandabbreviations

3.1Terms

Void.

3.2Symbols

Void.

3.3Abbreviations

Forthepurposesofthepresentdocument,thefollowingabbreviationsapply:

BSBaseStation

CPNCustomerPremisesNetwork

DCDirectCurrent

DLDownlink

DMADynamicMetasurfaceAntenna

EIRPEquivalentIsotropicallyRadiatedPower

EMElectroMagnetic

EMFElectroMagneticField

ETSI

eRG

FDD

FR

IoT

ISAC

KPI

LBT

LoS

LTE

M2M

MIMO

NLoS

NR

O2I

OFDM

PIN

QoS

RAT

RF

RIS

SNR

TDD

TRP

UAV

UE

UL

7

evolvedResidentialGateway

FrequencyDivisionDuplex

FrequencyRange

InternetofThings

IntegratedSensingAndCommunication

KeyPerformanceIndicator

ListenBeforeTalk

LineofSight

Long-TermEvolution

MachinetoMachine

Multi-InputMulti-Output

Non-LineofSight

NewRadio

OutdoortoIndoor

OrthogonalFrequencyDivisionMultiplexing

PersonalInternetofThingsNetwork

QualityofService

RadioAccessTechnology

RadioFrequency

ReconfigurableIntelligentSurfaces

SignaltoNoiseRatio

TimeDivisionDuplex

TransmissionandReceptionPoint

UnmannedAerialVehicle

UserEquipment

Uplink

ETSIGRRIS001V1.1.1(2023-04)

4Definition

4.0RISdefinition

RISisconsideredakeycandidatewirelesstechnologytrendforfuturenetworks.RIScorrespondstoanewnetwork nodecomposedofanarrangementofscatteringelementscalledunit-cells,whosepropertiescanbedynamically

controlledtochangeitselectromagneticbehaviour.TheresponseofRIScanbecontrolleddynamicallyand/or

semi-staticallythroughcontrolsignallingsuchastotunetheincidentwirelesssignalsthroughreflection,refraction,

focusing,collimation,modulation,absorptionoranycombinationofthese.AnillustrativediagramofRISisprovidedinFigure4.0-1,asanewnetworknodedynamicallyand/orsemi-staticallyconfiguredbytheRIScontroller,turningthe

wirelessenvironmentfromapassivetoanintelligentactorsuchthatthechannelbecomesprogrammable.Thistrend

willexpandbasicwirelesssystemdesignparadigms,creatinginnovationopportunitieswhichwillprogressivelyimpacttheevolutionofwirelesssystemarchitecture,accesstechnologies,andnetworkingprotocols.

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Figure4.0-1:IllustrativediagramofRIS,anewtypeofnetworknodewhere

itsresponsecanbeadaptedtothestatusofthepropagationenvironmentthroughcontrolsignalling

4.1Structure

4.1.0Generaloverview

RIScanbeimplementedusingmostlypassivecomponentswithoutrequiringhigh-costactivecomponentssuchaspoweramplifiers,resultinginlowimplementationcostandenergyconsumption.Thisallowseasyandflexible

deploymentofRIS,withthepossibilityofRIStakinganyshapeandtobeintegratedontoobjects(e.g.walls,buildings,lampposts,etc.).RISaresupposedtorunasnearly-passivedevicesandhenceareunlikelytoincreaseexposureto

EMF,andinfact,theycanpotentiallybeusedtoreduceEMpollutioninlegacydeployments.Theseassociated

characteristicssuggestRISmaybeconsideredasasustainableenvironmentallyfriendlytechnologysolution.RISmayhavedifferentstructureswithconsiderationsofcost,formfactor,designandintegration.

4.1.1Metamaterials

Metamaterialsandmeta-surfacesisanapproachtoimplementRIS.

Metamaterialsareartificialmaterialswhosepropertiescanbeengineered.Theyaretypicallysynthesizedusingmultipleelementsmadefromcompositematerialssuchasmetalsandplastics.

Athinmetamateriallayer,alsocalledameta-surface,couldrealizeadesiredtransformationoftransmitted,received,orreflectedElectroMagneticwaves.Ameta-surfacetypicallyconsistsofperiodicallyarrangedunitcells.

TheElectroMagneticpropertiesofameta-surfacemaybeelectronicallytuneableusingvariouscomponentsintegratedinthesurfacesuchasPINdiodes,varactordiodes,liquidcrystals,etc.

4.1.2Reflectarray

Reflectarraysuseelementaryantennasasreflectingelements.

Thereflectionproperties,suchasthephase,oftheelementscanbechangedby,e.g.varyingacontrollableload

connectedtoanantennaelement.Thereflectionoftheimpingingelectromagneticwavecanbecontrolledbycreatingaphasegradientonthearraybyselectingtheappropriatephaseresponsesofthecontiguouselementsofthearray.Hence,reflectarrayscanbeusedtoimplementRISunits.

Whentheelementspacingandantennaelementsonareflectarrayarereduced,reflectarraystendtobehaveasmeta-surfaces.

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4.2Hardwaredesign

4.2.0Typesofhardwaredesign

Inthisclause,differenttypesofcircuitdesignsofRISareprovided.RIScanbeseenasagenerichardwarerangingfrommeta-surfacesabletomanipulatewavepropagationinvery-richscatteringenvironmentstothoseabletorealizedesiredanomalousreflectionbeyondthewell-knownSnell'slaw.RIScanbedesignedtooperateindifferentmodeswhileexhibitingcomparableenergyefficiencywiththeirreflectivecounterparts.

NOTE:Thedefinitioninthisclauseisdescribedfrommanufacturingperspective,notfromoperatingperspective. ThismeansthataRISdefinedinthisclausecanworkunderanoperatingmodewhichdoesnotconsume power,thoughitwouldstillbeclassifiedasanactiveRISfromcircuitdesignperspective.

4.2.1ActiveRIS

ThetermactiveRISisadoptedwhenenergy-intensiveRFcircuitsandconsecutivesignalprocessingunitsare

embeddedinRIS.Onanothernote,activeRISsystemscompriseanaturalevolutionofconventionalmassiveMIMO

systems,bypackingmoreandmoresoftware-controlledantennaelementsontoatwo-dimensionalsurfaceoffinitesize.

TheactiveRISstructurecanbeusedtotransmitandreceivesignalsacrosstheentiresurfaceorusingaportionof

elements,makingitcapableofconductingmoretasksthanpassiveRIS.ARISstructureinwhichonlyaportionoftheelementsarecapableoftransmissionand/orreceptionissometimescalledsemi-active.

ThediscretephotonicantennaarrayisanotherpracticalimplementationofactiveRIS.Itintegratesactiveoptical-electricaldetectors,converters,andmodulatorsforperformingtransmission,reception,andconversionofopticalorRFsignals.

4.2.2PassiveRIS

PassiveRISactslikeapassivemetalmirrororwavecollectorwhichcanbeprogrammedtochangeanimpingingEMfieldinacustomizableway.Comparedwithitsactivecounterpart,apassiveRISisusuallycomposedoflow-costandalmostpassiveelementsthatdonotrequirededicatedpowersources.Theircircuitryandembeddedsensorscanbe

poweredwithenergyharvestingmodules,anapproachthathasthepotentialofmakingthemtrulyenergyneutral.

Regardlessoftheirspecificimplementations,whatmakesthepassiveRIStechnologyattractivefromanenergy

consumptionstandpoint,istheircapabilitytoshaperadiowavesimpinginguponthem,forwardingtheincomingsignalwithoutemployinganypoweramplifiernorRFchain,andevenwithoutapplyingsophisticatedsignalprocessing.

Moreover,inadditiontohalf-duplexmode,passiveRIScanalsoworkinfullduplexmodewithoutsignificantself

interferenceorincreasednoiselevel,andrequireonlylow-ratecontrollinkorbackhaulconnections.Finally,passiveRISstructurescanbeeasilyintegratedintothewirelesscommunicationenvironment,sincetheirextremelylowpowerconsumptionandhardwarecostsallowthemtobedeployedintobuildingfacades,roomandfactoryceilings,laptopcases,orevenhumanclothing.

4.2.3HybridRIS

AhybridRISiscapableofreflectingtheirimpingingsignal,whilesimultaneouslysensingaportionofit.HybridRISbearthepotentialofsignificantlyfacilitatingcoherentcommunicationswithoutnotablyaffectingtheenergyefficiencyandcoverageextensionadvantagesofferedbypassiveRIS.

AnexampleofanimplementationofaHybridRISisasurfacethatisloadedbyavaractor,whosecapacitancecanbechangedbyanexternalDCsignal.Thevaryingcapacitancecanchangethephaseofthereflectedwave.Inthisway,thephasevariationalongtheHybridRIScansteerthereflectedbeamtowardsdesireddirections.

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4.3Operatingmode

4.3.1Reflectionmode

TheconceptoftheRIS-empoweredsmartwirelessenvironmentsinitiallyconsideredonlypassiveRISwithalmostzeropowerconsumptionunitelements.Theirenvisionedprominentroleliesonthecapabilityofthesurfacetoreconfigurethereflectioncharacteristicsofitselements,enablingprogrammablemanipulationofincomingEMwavesinawide

varietyoffunctionalities.Itisessentialtoachieveafine-grainedcontroloverthereflectedEMfieldforquasi-freespacebeammanipulationsoastorealizeaccuratebeamforming.Meta-atomsofsub-wavelengthsizeareafavourablechoice,althoughinevitablestrongmutualcoupling,andwell-definedgrey-scale-tuneableEMpropertiesexist.

Conversely,inrichscatteringenvironments,thewaveenergyisstatisticallyequallyspreadthroughoutthewireless

medium.TheensuingraychaosimpliesthatraysimpacttheRISfromallpossible,ratherthanonewell-defined,

directions.Thegoalbecomesthemanipulationofasmanyraypathsaspossible,whichisdifferentfromthecommongoalofcreatingadirectivebeam.Thismanipulationhastwokindofaims,includingtailoringthoseraystocreate

constructivesuperpositionatatargetlocationandsteeringthefieldefficiently.ThesemanipulationscanbeefficientlyrealizedwithRISequippedwithhalf-wavelength-sizedmeta-atoms,enablingthecontrolofmorerayswithafixed

amountofelectroniccomponents(PINdiodes,etc.).Themeta-atomsareusuallyhalf-wavelength-sizedinlowerfrequencybands,whereasinhigherfrequencybandslikeFR2,theirsizesdependonmanufacturingconstraints.

RISworkinginreflectionmodecanactasareflectorintheenvironment,anditcanbeusedtoimprovecoverage,mitigateinterferenceandincreasecapacity.

4.3.2Refractionmode

TherefractionmodeallowsincidentEMwavespassingthroughtheRISandrefractthemtodifferenttargetdirectionsbyadjustingtheirphase.Themaindifferencebetweenrefractionandthereflectionmodecharacterizedinclause4.3.1isthemissingoftheshieldinglayerinsidetheRISpanel,whichenablestheEMwavestopassthroughthepanel.

Onetypicalusecaseofrefractionmodeisoutdoortoindoorscenario.Inordertoimprovethecoverageforsomecertainareasinsidethebuilding,theRISwillbeusedasthewindowglassesanditwillfocustheincidentEMwavesto

differenttargetareas.

4.3.3Absorptionmode

Undertheabsorptionmode,theimpingingradiowaveofacertaincenterfrequencyandacertainbandwidthcan,

ideally,betotallyabsorbedandnoreflectionwavecanbeobserved.Theabsorptionmode,thatallowsRIStohave

almostzerooutputwaves,canbebeneficialtointerferencemitigation,privacyandinformationsecurityindustry.OnetypicalusecaseistoimplementRISonthebuildingfacadetoshieldelectromagneticwave,sothattheelectromagneticwaveofindoorandoutdoorordifferentindoorroomswouldbeisolatedfromeachother.RISplanewillabsorbthe

incidentwavetopreventthemfrompenetratingbuildingwalls.TheswitchofRISbetweenabsorptionandrefractionorreflectionmodecanbecontrolledbybiasvoltage.

OneexampleofabsorptionRISisgraphenebasedRIS,whichcanreachnearly100%absorptioninsomegivenbandsaccordingtothedesign.Theperfectabsorptionisachievedbyelectricallyreconfiguringthemetaatomresponseviathechemicalpotentialofthegraphene.

4.3.4Backscatteringmode

ForaRISinbackscatteringmode,thereflectedwaveistocoveralargeareainsteadofanexactlocation.Therefore,thebalancebetweengainandeffectiveareaisnecessaryforrealizingwide-angleblindspotcoverage.BackscatteringmodecanbeusedforpassiveRIS,whicharemanufacturedtoreflectanimpingingEMsignalintoacertaindirection.

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11ETSIGRRIS001V1.1.1(2023-04)

4.3.5Transmittingmode

ARISintransmittingmodeisincorporatedinaradiotransmitterwiththeRISassistinginshapingthetransmittedradiowave.

Asanexample,DynamicMetasurfaceAntennas(DMAs)havebeenrecentlyproposedasanefficientrealizationof

extrememassiveantennaarrays.DMAshavebeamtailoringcapabilitiesandfacilitateprocessingofthetransmittedandreceivedsignalsintheanalogdomain.DMAsworkinadynamicallyconfigurablemannerwithsimplifiedtransceiver

hardware.Additionally,comparedwithconventionalantennaarrays,DMA-basedarchitecturesrequiremuchlesspowerandcost.Inthisway,eliminatingtheneedforcomplicatedcorporatefeedand/oractivephaseshiftersbecomespossible.AnotherpromisingadvantageofDMAsisthattheycancomprisemassivenumbersoftuneablemetamaterial-based

antennaelementsfittingintosmallphysicalareasandprovidingwiderangeofoperatingfrequencies.

DMAarchitecturethatconsistsofmultipleseparatewaveguide-fedelementarrayswitheachconnectedtoasingle

input/outputportisatypicalreflectingRIS.Alargenumberofradiatingelementscanbeaccommodatedinwaveguides,andthesub-wavelengthspacedcharacterallowseachinput/outputporttofeedamultitudeofpossiblycoupledradiators.For2Dwaveguides,ascatteredwavefromeachelementpropagatesinalldirections.Sincetheproposedwaveguideistypicallydesignedtobesinglemodeandthewavecanonlypropagatealongoneline,itsanalysisismucheasierthan

2Dwaveguides.Furthermore,ensuringisolationbetweendifferentportsiseasierin1Dwaveguidesthaninmultipleportsofa2Dwaveguide.

4.3.6Receivingmode

ARISinreceivingmodeiscapableofreceivingandprocessingradiosignals.ThiscanbeaccomplishedbyembeddingwaveguidesateachRISelement,orgroupofelements,todirecttheimpingingradiosignalstoreceptionhardware.Thishardwaremayinclude,forexample,alownoiseamplifier,amixerdownconvertingthesignalfromRFtobaseband,

andananalog-to-digitalconverter.

IntheexampleillustratedinFigure4.3.6-1,animpingingEMtrainingsignalattheRISelementsisreceivedintheRFdomainviaMRISphaseconfigurations,whicharerandomlyselectedthrougharandomspatialsamplingunit.This

collectionofspatiallyrandomanalogcombinedversionsoftheimpingingradiosignalsfacilitates,forexample,the

applicationofcompressed-sensing-basedchannelestimationtechniques,enablingsignalreceptionattheRISwithmuchlessreceptionRFchains(evenwithone)thanthenumberofRISelements.

Figure4.3.6-1:BlockdiagramofaRIShardwarearchitectureincluding

asingleactivereceptionRFchain,enablingthesensingoftheimpingingsignalinbaseband

4.4Operatingfrequency

4.4.0Description

ThisclausedescribespossibleoperatingfrequenciesforRIStobeintegratedintowirelessnetworks.TwoFrequencyRanges(FR