3GPP LTE Radio Physical Layer (India)-1.pdf

8/2/2019 3GPP LTE Radio Physical Layer (India)-1.pdf

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LTE R iLTE R i

Physical LayerPhysical Layer

Tetsushi Abe NTT DOCOMO

Vice-Chairman 3GPP TSG RAN WG1

3GPP Workshop 2 June, 2010, Chennai 1


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Introduction

UplinkAspectsforLTERelease8

n ancements or vance e ease an beyond)



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Releasesof3GPPspecifications

1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011

Release 99 W-CDMA

Release 4 1.28Mcps TDD

Release 6

,

HSUPA, MBMS, IMS+

Release 7 HSPA+ (MIMO, HOM etc.)

ITU-R M.1457Release 8 LTE, SAEIMT-2000 Recommendations

Release 9Small LTE/SAEenhancements

Unser process

3GPP Workshop 2 June, 2010, Chennai 3LTE-AdvancedRelease 10


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TS36.201EUTRAPhysicallayer:Generaldescription.TS36.211EUTRAPhysicalchannelsandmodulation.

TS36.212EUTRAMultiplexingandchannelcoding.

TS36.213EUTRAPhysicallayerprocedures.TS36.214EUTRAPhysicallayer Measurements

Thelatestversionofthespecificationscanbedownloaded

from:

http: www.3gpp.org ftp Specs



5/53

AccessScheme DL OFDMA

UL SCFDMA

Bandwidth 1.4,3,

5,

10,

15,

20

MHz

MinimumTTI 1ms

Cyclicprefixlength Short 4.7s.

Modulation QPSK,16QAM,64QAM

Upto4layersforDLperUE


suppor e or an


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One downlink slot, Tslot

Basicunitofresourceisthe

Physical

Resource

Block

12subcarriersx0.5msiersiers

domain)

rriers

rriers

Resource element

N

BW

subc

ar

RB

N

BW

subc

ar

RB

resourceelement(RE)

S atial domain measured

subc

N

BW

DL

subc

N

BW

DL

N

BW

DL

sourceblock,

sourceblock,

inlayers Oner

Oner

3GPP Workshop 2 June, 2010, Chennai 6OFDM symbolsDLsymbN OFDM symbolsDLsymbN


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,

SupportsbothFDDandTDD(twoRITswithinoneSRIT)

FDD

TDD



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Introduction


En ancements orLTEA vance Re ease10an beyond)



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Cellac uisitionsi nallin

Synchronisationsignalsinsubframes0and5ofeach10msradioframe

UsedininitialcellsearchP ysica roa castc anne PBCH insu rame0o eac ra io rame

CarriestheMasterInformationBlock(MIB)

Includesindicationofsystembandwidth o us es gn orce w ecoverage:

Lowrate,QPSK,robustchannelcoding(1/3ratetailbitingconvolutionalcodewithrepetition),40msTTI

40ms TTI of BCH

1 coded MIB

sd

6RB

3GPP Workshop 2 June, 2010, Chennai 9one 10 ms radio frame


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InRel8,cellspecificRSareprovidedfor1,2or4antenna

Patterndesignedforeffectivechannelestimation

S arsediamond atternsu ortsfre uenc selectivechannelsandhi hmobilitywithlowoverhead

Upto6cellspecificfrequencyshiftsareconfigurable

ower oos ngmay eapp e on e suse or

QPSKsequencewithlowPAPR

Antenna ort 0 Antenna ort 2Antenna ort 1 Antenna ort 3

R3

RR

R0

R

R0 R1

R

R1

R R

R2

requency

R3

R3R0

0

R0

R0

0

R0 R1

R1

1

R1

R1

1

R2

R2

f


time


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5R 5R

InRel8:

UE

specific

(precoded)

RS

may

be

provided

in

5R

5R

5R

5R

5R

5R

5R

5R

5R

5R

UEspecificRSextendedtoduallayertransmission

CDMbetweenRS

0=l 0=l 6=l6=l

7R7R7R7R 8R 8R8R 8R

ofthetwolayers

7R7R7R7R 8R 8R8R 8R

7R

7R

7R

7R

8R

8R

8R

8R



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Flexiblecontroldesigntoavoidunnecessaryoverhead

narrowbandwidths)

Control

region

size

(CFI:

control

channel

format

indicator)

is

d namicall variable

Downlink control channel re ion

DatatransmissiononPhysicalDownlinkSharedChannel(PDSCH)

TimeCFI=1CFI=3 CFI=2

PDSCH PDSCH PDSCH

Frequency


Subframe


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thecontrolregionsize(CFI)

LocatedinfirstOFDMsymbolofeachsubframe

PCFICHisdesignedtoberobust

16QPSKsymbolstransmittedwithfullfrequencydiversity

PhysicalDownlinkControlChannel(PDCCH)carriesDownlinkControlInformation(DCI)messages:

own in resourceassignments

uplinkresourcegrants

PhysicalHybridARQIndicatorChannel(PHICH)carries



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,

broadcastsysteminformation,

pagingmessages

One subframe = 1 ms

12 subcarriers

Transmissionresourcesare

assigneddynamicallybyPDCCH

Localised(suitableforfrequencydomainscheduling)

(localised)

or

distributed(suitableforData for UE2:

(distributed)

diversity)Data for UE3:



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,

modesforPDSCHreception:

Mode 1: Sin le antenna ort ort 0

Mode2:Transmitdiversity

Mode3:LargedelayCDD

Mode4:

Closed

loop

spatial

multiplexing

Mode5:MUMIMO

o e : ose oopspa a mu p ex ng,s ng e ayer

Mode7:Singleantennaport,UEspecificRS(port5)

Mode8 newinRel9 :Sin leordualla ertransmissionwithUEspecificRS(ports7and/or8)

(ineachcase,transmitdiversityisalsoavailableasafallback)



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Introduction

DownlinkAspectsforLTERelease8


En ancements

or

LTE

A vance

Re ease

10

an

beyond)



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Sameparameterisationasdownlink

DFTprecodingtoensurelowPAPR/cubicmetric

equalisationateNodeB



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One subframe = 1 ms

SamestructureofPRBsinfrequency

domainasdownlink

on guous a oca on o eep

singlecarrierproperty

12 sub-carriers

hoppingtoincreasefrequency

diversit

NumberofallocatedPRBsfora

givenuserinagivensubframeisinmultiplesof2,3and5forlow

complexityDFTimplementation



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DemodulationRS(DMRS)

SoundingRS(SRS)

Su orts:

ULfrequencydomainscheduling Channelsoundingfordownlinktransmissions,especiallyforTDD

oca e n as sym o o asu rame

Canbeconfiguredbynetwork

provideadditionalsupportformultipleuserstransmittingSRSinthe

samebandwidth



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DatatransmissionsonPhysicalUplinkSharedChannel(PUSCH)

Minimisesoutofbandemissionsfromwidebandwidthdatatransmissions

1transportblockperTTI

0=m1=m1ULRBPRB = Nn

Samechannelcoding/ratematchingasPDSCH

ModulationQPSK,16QAM,64QAM

2=m3=m ,

controlsignallingismultiplexedwithdatatomaintainsinglecarrier

PUSCHWhennoPUSCH,controlsignalling

isonPhysicalUplinkControlChannel

PUCCH

0=m 1=m

2=m 3=m

0PRB =n

PUCCH

Usuallyatedgesofsystembandwidth

PUCCHho sfromonesideofthecarrierto

3GPP Workshop 2 June, 2010, Chennai 20One subframe

theothertomaximisefrequencydiversity


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ACK/NACKforPDSCHtransmissions

SchedulingRequest(SR)ChannelQualityInformationfeedbackcanbe

eriodic on PUCCH or a eriodic on PUSCH

CQI indicatesanindexofaModulation/CodingScheme(MCS)thatcouldbereceivedonPDSCHwithBLER 0.1

PMI indicatespreferredprecodingmatrixforPDSCH

RI indicatesnumberofusefultransmissionla ersforPDSCH



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RACHprocedurebeginswithapreamble(PRACH)

PRACHresourcesassignedbyeNBwithinPUSCHregion

PRACHpreamblefitsinto6PRBs Sufficientfortimingestimation

Invariantwithbandwidthforlowcom lexit

PUSCH

ZadoffChusequence Excellentcorrelationproperties

PRACH

cyclicshifts

Flatfrequencyspectrum

differentcyclicshifts,thenbydifferentrootsequences



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Uplinktransmissionorthogonalitybetweenusersis

maintainedbytimingadvance

SetinitiallyduringRandomAccessProcedureUpdatedasnecessarysubsequently

Supportsatleast100kmcellrange

Greaterrangesareuptotheimplementation

Uplink radio frame #i


NTATS time units


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ontro sup n powerspectra ens ty

Totaluplinktransmitpowerscaleslinearlywithtransmittedbandwidth

loss

Allowstradeoffbetweenintracellfairnessandintercellinterference

MCS

specific

offsets

may

be

appliedClosedlooppowercontrolcommandscanfinetunethepower

se ng

CarriedonPDCCH

IndividualcommandsinULresourcegrants GroupcommandsforgroupsofUEs

SeparatepowercontrolforPUCCHandPUSCH



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Rel8/9supports:

Switchedantennadiversity ClosedloopantennaswitchingsupportedbyCRCmaskingon

PBCH

DifferentcyclicshiftsofDMRScanbeallocatedtodifferentUEs



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Introduction

DownlinkAspectsforLTERelease8UplinkAspectsforLTERelease8

(Release10andbeyond)

Note that discussion on Rel-10 features described in the followin slides are still on oin at 3GPP


and the specifications are not yet finalized.


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SystemPerformanceRequirementsfor

LTEAdvanced

ea atarate

1Gbpsdataratewillbeachievedby4by4MIMOandtransmission

bandwidthwiderthanapproximately70MHz

Peakspectrumefficiency

DL:Rel.8LTEsatisfiesIMTAdvancedrequirement

UL:NeedtodoublefromRelease8tosatisfyIMTAdvanced

requirement

Rel. 8 LTE LTE-Advanced IMT-Advanced

Peak data rateDL 300 Mbps 1 Gbps

1 Gbps(*)UL 75 Mbps 500 Mbps

Peak spectrum efficiency DL 15 30 15ps/ z

UL 3.75 15 6.75

*100 Mbps for high mobility and 1 Gbps for low mobility is one of the key features as written inCircular Letter (CL)



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SystemPerformanceRequirementsfor

LTEAdvanced(contd)

Capacityandcelledgeuserthroughput TargetforLTEAdvancedwassetconsideringgainof1.4to1.6fromRelease8LTE

performance

Ant. Config. Rel. 8 LTE*1 LTE-Advanced*2 IMT-Advanced*3

Capacity[bps/Hz/cell]

DL 2-by-2 1.69 2.4

- -

4-by-4 2.67 3.7 UL 1-by-2 0.74 1.2

- -

x1.4-1.6

Celledgeuser

throughput

[bps/Hz/cell/use

DL 2by2 0.05 0.07

4by2 0.06 0.09 0.06

. .

r] 4by4 0.08 0.12

UL 1by2 0.024 0.04

2by4 0.07 0.03


*1 See TR25.912(Case 1 scenario) *2 See TR36.913(Case 1 scenario)*3 See ITU-R M.2135(Base Coverage Urban scenario)


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TargetdeploymentscenariosforLTEAdvancedcoverbothhomogeneous

andheterogeneousnetworks.

High-power node

Low-power node

Homogeneous network deployment Heterogeneous network network

Evaluationmodelsforeachdeploymentscenarioin3GPPisshownin

TR36.814ver.9.0.0(Annextherein)



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CarrieraggregationforLTE

Enhanced

multi

antenna

downlink

transmission

for

LTEUplinkmultipleantennatransmissionforLTE

RelaysforLTE

Enhanced

ICIC

for

non

CA

(carrier

aggregation)

based

deploymentofheterogeneousnetworks

NetworkpositioningsupportforLTE



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CarrierAggregation(CA)

WiderbandwidthtransmissionusingcarrieraggregationforbothDLandUL

Entires stembandwidthu to,e. .,100MHz,com risesmulti lebasicfre uenc blockscalledcomponentcarriers(CCs)

Satisfyrequirementsforpeakdatarate

EachCCcanbeconfi uredinabackwardcom atiblewa withRel8LTE

MaintainbackwardcompatibilitywithRel8LTE

Carrieraggregationsupportsbothcontiguousandnoncontiguousspectrum,andasymmetricbandwidthforFDD

Achieveflexiblespectrumusage

System bandwidth, CC, e.g., 20 MHz

Frequency

. .,

Examples of

UE ca abilities 100-MHz case

40-MHz case


-(Rel. 8 LTE)


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DownlinkMultipleAccessScheme

Downlink: OFDMA with component carrier (CC) based structure

r or y g ven o reus ng e . spec ca on or ow-cos an as eve opmen

Transport Transport Transport Transportblock block block block

withinoneCC

Paralleltypetransmissionover

coding

HARQ

coding

HARQ

coding

HARQ

coding

HARQ

mu p e s

Mod. Mod. Mod. Mod.GoodaffinitytoRel.8LTE

specifications

app ng app ng app ng app ng

CC

PDCCHinoneCCcanschedulePDSCHinanotherCC



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Uplink: N-times DFT-Spread OFDM

-

Satisfy requirements for peak data rate while maintaining backward

compatibility- .

Will also support non-contiguous resource allocation

Enhanced flexibility and efficiency of resource allocation

Simultaneous PUCCH and PUSCH transmission will be supported.Independent power control will be provided per CC

- -

CC CCPUCCH region

Freq.Parallel Rel. 8 LTE

3GPP Workshop 2 June, 2010, Chennai 33(Physical uplink shared channel)


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EnhancedDownlinkMultiantenna

Extensionupto8layertransmission

Increasedfrom4la ersinRel8 9

Satisfytherequirementforpeakspectrumefficiency,

i.e.,30bps/Hz

Additionalreferencesi nals RS s ecified:

Max. 8 streams

ChannelstateinformationRS(CSIRS)

Fordownlinkchannelsounding

Sparse,lowoverhead(configurable)

Density:1resourceelement(RE)perantennaportperPRB

UEspecificdemodulationRS(DMRS)

,

precoding,

applied 18layer transmission, and enhanced

, DM RS pattern for higher numbers of layers is

extended from 2layer format for transmission

mode 8 in Rel9


DMRS pattern


35/53

EnhancedDownlinkMultiantenna

ransm ss on

on

n ance u user

CSIfeedback

Maximumspatial4layers

Maximum2layersperuserEnhancedMU-MIMO

CSIfeedbackenhancementusingtwomatrix(W1,W2)feedbackframeworkisnowbeingstudied

W1targetswideband/longtermchannelproperties

W2targetsfrequencyselective/shorttermtimechannelproperties

.



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EnhancedUplinkMultiantenna

Transmission-

Orthogonal resource transmit diversity is supported for PUCCH format 1 (Schedulingrequest) 1a/1b (HARQ-Ack) when UE has two Tx antennas

antenna ports, on two separate orthogonal resources.

- -

spectrum efficiency, i.e., 15 bps/Hz Closed-loop codebook based precoding supported

SU-MIMO up to 4 streams

Max. 4 streams



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RelayingforLTE

RelaydesigntargetforRel10iscoverageextension

Supportscelldeploymentsinareaswherewiredbackhaulisnotavailableorveryexpensive

Type1relay

Inbandrelaying:samecarrierfrequencyforbackhaulandaccesslinks

Relaynode(RN)createsaseparatecelldistinctfromthedonorcell

UEreceives/transmitscontrolsignalsforschedulingandHARQfrom/toRN

RNa earsasaRel8LTEeNBtoRel8LTEUEs

Type

1a

relay Outbandrelaying:differentcarrierfrequencyforbackhaulfromaccesslink

Relay node (RN)Macro (eNB)

UE

Backhaul link Access link



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LTEAdvancedisaveryflexibleandadvancedsystem

BuiltontheestablishedcapabilitiesoftheLTERel8andRel9physicallayer

Furtherenhancementstoexploitspectrumavailabilityan a vance mu t antennatec n ques



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CoMP reception scheme in uplink

ys ca up n s are c anne s rece ve a mu p e ce s Scheduling is coordinated among the cells

Improve especially cell-edge user throughput Note that CoMP reception in uplink is an implementation matter and

does not require any change to radio interface

Receiver signal processing atcentral eNB (e.g., MRC, MMSEC)



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LTERelease8UserEquipment

Categories

Category 1 2 3 4 5

Peakrate

Mbps

DL 10 50 100 150 300

UL 5 25 50 50 75

Capabilityforphysicalfunctionalities

RFbandwidth 20MHz

Modulation DL QPSK,16QAM,64QAM

UL QPSK,16QAM QPSK,

16QAM,

Multiantenna

2

Rx

diversity Assumed

in

performance

requirements.2x2MIMO Not

supported

Mandatory

4x4MIMO Notsu orted Mandator



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Mode2:

SFBCfor2antennaports

SFBC/FSTDfor4antennaports

LargedelayCDD increasesfrequencyselectivity

Allowsopenloopspatialmultiplexing

Uptorank2withoutclosedloopprecodingfeedbackfromUE

Mode4:

Preco ingusingspeci ie co e oo ort ere evantnum ero antennaports

Supports

up

to

4

layers Max2codewordstolimitsignallingoverhead

ClosedloopprecodingfeedbackfromUE



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DetailsofPDSCHtransmissionmodes(2)

Mode5:

BasedonsameprecodingcodebooksandfeedbackasMode4

PDCCHindicates

power

offset

for

PDSCH

Mode6:

Basedonmode4butforsinglelayeronly

o e :

UEspecificRS SuitableforUEspecificbeamforming,e.g.basedonangleofarrival

(noclosedloopprecodingfeedbackfromUE)

Mode8:

ua ayer spec c

Closedloopprecodingfeedbackmayormaynotbeused

SupportsduallayerSUMIMOandsinglelayerMUMIMO



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SupportsSingleFrequency

Networkoperationforhigh

R4

R4

4

R4

subframes

Ph sicalMulticastChannel PMCH R4

4

R4

R4

4

isusedinsteadofPDSCH

SpecialRSpatternwithhigherR4

R4

4

R4

supportslongerdelayspread

frommulticelltransmission R4

R4

R4

R4

4

even-numbered slots odd-numbered slots



45/53

Introduction

DownlinkAspectsUplinkAspects

SpecificsupportforhalfduplexFDD

UEcategoriesinRel8



46/53

opera on

Specialtimeslotfordownlinkuplinkswitching:

DL UL

DwPTS

subframe #0

SSS PSS

subframe #2

UpPTSRS/ControlData

TDD

operation

is

also

supported

by: AnincreasednumberofHARQprocesses

ACK/NACKbundling/multiplexingconfigurationstoenablecontrolsi nallin tobetransmitted



47/53

Introduction

DownlinkAspectsUplinkAspects

SpecificsupportforhalfduplexFDD

UEcategoriesinRel8



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,

ForDLULswitchingtime,UEignoresendofDLsubframe

canbeappliedtotheULtransmissions

1 ms subframe

UL-to-DL switch time created

by timing advance

DL-to-UL switch time created by the UE

ignoring the last part of the DL subframe



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Downlink:OFDMA

Highspectralefficiency

Intersymbolinterferencecontainedwithincyclicprefix

Supportsflexiblebandwidthdeployment

Facilitatesfrequencydomainscheduling

WellsuitedtoadvancedMIMOtechniques

Uplink:SCFDMA

BasedonOFDMAwithDFTprecoding

ommons ruc ureo ransm ss onresourcescompare o own n

Cyclicprefixsupportsfrequencydomainequalization

Low Cubic Metric for efficient transmitter desi n



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Synchronisationsignalsandbroadcastchannel:

Fixed

bandwidth Centrallylocated

Allowsstraightforwardbandwidthagnosticcellsearch

Synchronisation signalsand physical broadcastchannel


requency

PDSCH physical layer processing


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PDSCHphysicallayerprocessing

Each TTI,1or2transportblocksare110 ,...,, Aaaa

Channelcodingisbasedon1/3rateturbo

codewithtrellisterminationtoa roach

110 ,...,, Bbbb

Shannoncapacity

Circularbufferratematching( )110 ,...,, rKrrr ccc

ModulationQPSK,16QAM,64QAM

Layermappingandprecodingforsupportof( ))(

1

)(1

)(0 ,...,,

i

Dr

i

r

i

rr

ddd

( )110 ,...,, rErrr eee

110 ,...,, Gfff



52/53

Carrierindicatorfield(CIF)canbesemistaticallyconfiguredtoenable

crosscarrierULandDLassignments

DL/UL Data

freq.CC2CC1

Use PDCCH in CC1 toschedule PDSCH in CC2

Possibleapplication iscontrolchannelintercellinterferencecoordination

(ICIC)onheterogeneousnetworks

Macrocell

Pico/femto cell Macrolayer

Freq.

Pico/femtolayer


CC1

Control channel design for relay


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Controlchanneldesignforrelay

RPDCCH isdesignedtodynamicallyorsemiersistentl assi nresourcesforthedownlinkbackhaul

data(correspondingtotheRPDSCHandRPUSCH

physical

channel).

DLgrantsarealwaystransmittedinthefirstslotofasubframe

IfaDLgrantistransmittedinthefirstPRBofagivenPRBpair,t enan grantmay etransm tte nt esecon o t e

PRBpair

pair

ULgrantsareonlytransmittedinthesecondslot Nodatatransmissioninthefirstslot

Ongoingdiscussionsoninterleaving.


OnlyRank1issupportedforRPDCCHforagivenRN

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3GPP LTE Radio Physical Layer (India)-1.pdf