965303006

Inter Cell Interference mitigation

in OFDMA cellular system

(98 4 )

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: 965303006

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99 6 24

1. 15 3

http://thesis.lib.ncu.edu.tw/

2.

3.

4.

i

OFDMA

(Inter cell interference)

ii

Inter Cell Interference mitigation in

OFDMA cellular system

AdvisorDr. Yung-Fang Chen StudentChin-Ming Hu

Abstract

With the fast development of the wireless communications, the requirement

of faster transmission rate has also increased rapidly. The OFDMA technology

is considered as a promising candidate for the downlink interface of the next

generation wireless systems. However, inter cell interference is an impediment

of the throughput performance in the system, especially for Cell Edge

Users(CEUs).The main goal is to improve the CEU throughput as well as

overall cell throughput.

In this thesis, we propose a flexible softer frequency reuse scheme. Several

schemes on inter cell interference coordination have been suggested for

OFDMA systems. Our algorithm is designed to improve the CEU throughput by

optimizing the reuse factorpower factor and packet scheduler priority. From the

simulation result, the proposed algorithm can increase the CEU throughput

effectively.

iv

................................................................................................................ i

Abstract ................................................................................................................. ii

..................................................................................................................... ii

.................................................................................................................. iv

.......................................................................................................... vi

.......................................................................................................... ix

....................................................................................................... 1

1-1 ................................................................................................. 1

1-2 ................................................................................................. 1

1-3 ................................................................................................. 3

OFDMA LTE .................................................................... 4

2-1 OFDM ..................................................................................... 4

2-2 OFDMA .................................................................................. 6

2-3 LTE ................................................................................................. 8

2-3-1 LTE ............................................................................... 8

2-3-2 LTE ............................................................................. 10

................................................................................... 13

3-1 PFR (Partial Frequency Reuse) ................................... 15

v

3-2 SFR (Soft Frequency Reuse) ....................................... 17

3-3 SerFR (Softer Frequency Reuse) ................................. 18

3-4 Flexible Softer Frequency Reuse ..................... 21

................................................................................... 27

4-1 ................................................................................... 27

4-2 ....................................................................... 28

................................................................................... 37

5-1 ............................................................................ 37

5-1-1 ................................................................. 37

5-1-2 ..................................................................................... 39

5-2 ........................................................................................ 40

5-2-1 ............................................................................. 40

5-2-2 Outage rate Forced termination rate .............................. 43

5-2-3 Residual PER ...................................................................... 47

5-2-4 Throughput ......................................................................... 48

................................................................................... 54

............................................................................................................. 55

vi

1-1 Reuse 1 scheme .......................................................................................... 2

1-2 Reuse 3 scheme .......................................................................................... 3

2-1 .................................................................................. 4

2-2 ................................................................................................... 5

2-3 OFDMA ................................................................................ 6

2-4 OFDMA ................................................................................ 7

2-5 OFDMA .................................................................................... 7

2-6 OFDMA SC-FDMA QPSK (Data symbol) ..... 8

2-7 UTRAN ............................................................................... 10

2-8 LTE ..................................................................................... 11

3-1 The cell-specific interleaving ................................................................... 14

3-2 Partial Frequency Reuse Cell Layout ...................................................... 15

3-3 Spectrum for Partial Frequency Reuse .................................................... 16

3-4 Frequency-Power arrangement for Soft Frequency Reuse ...................... 18

3-5 Frequency Planning for SerFR (frequency reuse 1) ................................ 19

3-6 Power profile for SerFR ........................................................................... 19

3-7 Priority Tables for SerFR ......................................................................... 21

vii

3-8 A seven cell hexagonal cell layout .......................................................... 22

3-9 ............................................................................ 23

3-10 ................................................................................... 25

3-11 A band .................................................................................................... 25

3-11 B band .................................................................................................... 26

4-1 RRC Connection .................................................................... 30

4-2 Re-allocation ............................................................... 33

4-3 Subcarrier opportunistic proportional fair .................................. 34

4-4 .................................................................... 36

5-1 ..................................................................................... 37

5-2 ............................................................................ 39

5-3 ................................................................................ 41

5-4 (10~60) ........................................... 42

5-5 (10~30) ........................................... 43

5-6 Outage rate user number ........................................................ 44

5-7 PFR SFR Outage rate user number .............................. 45

5-8 Forced termination rate user number ..................................... 46

5-9 PFR SFR Forced termination rate user number .......... 46

5-10 Residual PER user number .................................................. 48

viii

5-11 5th percentile throughput ...................................................... 49

5-12 85th percentile throughput .................................................... 50

5-13 5th percentile throughput ............................................ 51

5-14 85th percentile throughput .......................................... 52

5-15 5th 85th percentile throughput ............................... 52

5-16 Overall throughput .......................................................... 53

ix

2-1 OFDMA .................................................................... 9

2-2 RB ......................................................................... 10

3-1 PRB ........................................................... 23

5-1 ......................................................................................... 38

5-2 ITU Multipath fading ................................................ 40

5-3 CEU Proposed FR FR ................................... 49

5-4 CCU Proposed FR FR .................................. 50

1

1-1

(Apple)iPhone

OFDMA

IEEE802.16e

3G LTE (3rd Generation Long Term Evolution)

OFDMAOFDMA

(Cell)(inter cell interference)

(cell edge)(throughput)

1-2 ICI(Inter cell interference)

(Frequency Reuse)

Reuse 1(Resource

Block)(cell throughput)

(cell edge user, CEU)(sub-carriers)

(Signal to

Interference and Noise Ratio, SINR)(Shannons theorem)

CEUthroughputReuse 33

3(Tri-sector)

2

SINR

CEU throughput

(cell center user,CCU)throughput

CEU(Cell Edge User)throughput

(system throughput)CEUthroughput

(flexible)(reuse factor)

1-1 Reuse 1 scheme

3

1-2 Reuse 3 scheme

1-3 3GPP ,OFDMA

OFDMALTE

OFDMALTE

PFR(Partial

Frequency Reuse)[1]SFR(Soft Frequency Reuse)[2]SerFR(Softer

Frequency Reuse)[3]

Matlab

4

OFDMA LTE

OFDMA(Orthogonal Frequency Division Multiple Access)

OFDMWorldwide Interoperability for Microwave Access

(WiMAX)3G Long-Term Evolution (LTE)OFDMA

OFDMA

2-1 OFDM OFDM

2-1

OFDMM

(M-PSK)(QAM)

iTstfeCtsiTstfkj

i

Nsc

k

ki

2

1 (2.1)

tstGtstGt

tf

,1

,,0 (2.2)

5

ts

fts

kkf

1,

1

(2.3)

tsGTs (2.4)

Ts

Nsc

TR

1 (2.5)

Nsc(subcarrier) kC ki

(information symbol) fk ksubcarrierTs

G (Guard Interval)ts Ts

ISI(Inter Symbol Interference)OFDM symbol

G (Guard time)(delay

spread)symbol(multipath)

symbolICI(Inter carrier Interference)

FFT(Fast Fourier Transform)subcarrier

ICI(Inter carrier Interference)OFDM symbol

(Cyclic

Prefix)symbolFFT

2-2

6

2-2 OFDMA OFDMAOFDM3GPP

LTEWiMaxOFDMA

IFFT(Inverse Fast Fourier Transform)

2-3 OFDMA

TDMA(Time division multiple access)FDMA(Frequency division

multiple access)TDMA

useruser

FDMAuserOFDMA

2-44user

4usersymbol

7

2-4 OFDMA

OFDMAmultiplex

userCQI(Channel Quality

Information)2-5

2-5 OFDMA

8

2-3 LTE

2-3-1 LTE LTE3GPP Long Term EvolutionUMTS(Universal

Mobile Telecommunications System)LTE

OFDMAQPSK16QAM64QAM

SC-FDMA(Single Carrier-Frequency Division Multiple Access)

BPSKQPSK8PSK16QAM

PAPR(Peak-to-Average Power Ratio)UE2-6

OFDMASC-FDMAQPSK(Data symbol)

2-6 OFDMASC-FDMAQPSK(Data symbol)

OFDMA15K Hzsubcarrier

66.7ssymbolQPSKsymbol

symbolCPsymbolSC-FDMA

OFDMAsymbol

4OFDMAcarriersymbol

OFDMA(multi-carrier)

9

3GPP36Specification seriesE-UTRA(Evolved Universal

Terrestrial Radio Access)OFDMAsubcarrier(spacing)

15K HzCP4.7/16.7s (short/long CP)FDDTDD

FDDframe10ms20sub-framesub-frame

0.5msOFDMA

Transmission

BW

1.25

MHz

2.5 MHz 5 MHz 10 MHz 15 MHz 20 MHz

Sub-frame

duration

0.5 ms

Sub-carrier

spacing

15 kHz

Sampling

frequency

1.92

MHz(1/

2 3.84

MHz)

3.84

MHz

7.68

MHz (2

3.84

MHz)

15.36

MHz (4

3.84

MHz)

23.04

MHz (6

3.84

MHz)

30.72

MHz (8

3.84

MHz)

FFT size 128 256 512 1024 1536 2048

Number of

occupied

sub-carriers

76 151 301 601 901 1201

Number of

OFDM

symbols per

sub frame

(Short/Long

CP)

7/6

CP

length

(s/sa

mples)

Short (4.69/9)

6,

(5.21/10

) 1*

(4.69/18)

6,

(5.21/20)

1

(4.69/36)

6,

(5.21/40)

1

(4.69/72)

6,

(5.21/80)

1

(4.69/108

) 6,

(5.21/120

) 1

(4.69/144

) 6,

(5.21/160

) 1

Long (16.67/3

2)

(16.67/64

)

(16.67/12

8)

(16.67/25

6)

(16.67/38

4)

(16.67/51

2)

2-1 OFDMA

10

LTE(Radio Resource allocation)

(Resource Block)RBRB180k Hz1215 k

Hz subcarrierRB[14]

Channel

bandwidth 1.4 3 5 10 15 20

NRB 6 15 25 50 75 100

2-2 RB

2-13.84M Hz

(3G)4G

2-3-2 LTE LTEUTRAN(UMTS Terrestrial Radio

Access Network)Node BRNCRNC

Iu-CSMGWMSCIu-PSSGSNRNCIur

IubNode BRNC2-7

2-7 UTRAN

11

3GPPRANRNC

eNode B

(Delay)2-8LTEUE

E-UTRANEPC(Evolved Packet Core Network)UuUE

eNode BeNodeBX2EPC

2-8 LTE

EPCMME(Mobility Management Entity)SAE GW(System

Architecture Evolution)PCRF(Policy and Charging Resource Function)

HSS(Home Subscription Server)MME

SAE GWtracking area(3GLAC)

(transport bearers)SAE GWeNode B

12

PCRFQosHSS

13

(Frequency reuse)Bell LAB1947

(Inter cell interference)OFDMA

(CEU)Throughputthroughput

Inter-cell interference mitigation3GPP[4]

Inter-cell-interference randomization

Inter-cell-interference cancellation

Inter-cell-interference co-ordination/avoidance

inter-cell-interference randomization

(randomizing)Cell-specific scrambling

(scrambling)(coding/interleaving)

(pseudo)

(uniform)(CEU)

UMTS(scrambling code)

(average)Cell-specific

interleavingInterleaved Division Multiple Access (IDMA)

PHYForward error correcting (FEC)Coded

bit-level (interleaving)(modulation)OFDMA

mapping3-1(frequency

hopping)

14

3-1 The cell-specific interleaving

cell-specific scrambling cell-specific interleaving (IDMA)

(Performance)

Inter-cell-interference cancellationUE

(processing gain)3GPP

TR_25.814 UE(multiple antennas)

(Spatial suppression)UE

E-UTRAIDMA based Inter-cell-interference cancellation

1 (Resource Block)cellUE

(code block)cellUE

(set)

2 NodeB(Inter-NodeB)

3 cancellationUENodeB

IDMA(interleaver pattern ID)

UE

4 interleaver pattern ID, modulation scheme, FEC

scheme coding rateUENodeB

(inter-NodeB interference)UE

NodeB(controlling channel)

UE(inter-sector

interference)

15

Inter-cell-interference co-ordination/avoidance

(downlink resource management)(common

channels)

SIRCEUInter-cell

interference co-ordination

3GPP LTE

[5]

PFR(Partial Frequency Reuse)SFR(Soft Frequency Reuse)SerFR(softer

Frequency Reuse)

3-1 PFR (Partial Frequency Reuse) (Partial Frequency Reuse)2006(Siemens)

[1](Partial Reuse)

F1F3F3(subset)(sub band)

F1F3AF3BF3C3-2

3-2 Partial Frequency Reuse Cell Layout

16

NodeB3F3AF3B

F3C(BW) 3-3F1

(cell center band)(reuse factor)1

SINR

CCU(cell center user)F3(cell edge band)

(reuse factor)3

SINRCEU(cell edge user)

CEUCCUCEU

F3CCU

3-3 Spectrum for Partial Frequency Reuse

(effective reuse factor)

(3.1)

3F3

11F

3F1F

BWBW

BWBW

BW

BWr

cell

alleff

(3.1)

1Reuse 1 effr =13Reuse

17

3 effr =31-11-2F1(3.2)F3

(3.3)

eff

eff

allreuser

rBWBW

2

31

(3.2)

eff

eff

allreuser

rBWBW

2

333 (3.3)

allBW BWreuse1 BWreuse3cell

BWreuse1BWreuse3

3-2 SFR (Soft Frequency Reuse) (Soft Frequency Reuse)2005(Huawei)

[2]CEU

3

(cell edge band)cellCEU

CCU3-4

CEUCCUCEU

(major subcarrier group)CCU(minor

subcarrier group)3-4

edge bandchunk

cell center band

(3)2

CEUCCUCEU

CCU

18

3-4 Frequency-Power arrangement for Soft Frequency Reuse

3-3 SerFR (Softer Frequency Reuse) (Softer Frequency Reuse)2008Xunyong Zhang

[3]SFR(frequency

selective scheduling gain)CEUcell edge band

CEUthroughputSerFRSerFRCCUCEU

13-5

3-671357

246

19

3-5 Frequency Planning for SerFR (frequency reuse 1)

3-6 Power profile for SerFR

CEUSerFRCEU

(Proportional Fairness)

throughput(Trade-off)

20

Round RobinRound Robin

TTI

throughputTTI

k-thnj-th RB

(3.4)

)(

)()(

,,

nR

nDRCnp

k

jkjk

(3.4)

DRCk,j(n)k-thnj-th RBthroughput

Rk(n)k-ththroughputnRk(n)

(3.5)

)()(1)1( nCDRnRnR kkk (3.5) DRCk(n)k-thnthroughput(forgetting

factor)

SerFR(3.4)(3.6)

jk

k

jkjk

nR

nDRCnp ,

,,

)(

)()(

(3.6)

k,j ,

11 ,kRBj

12 ,kRBj

21 ,kRBj

22 ,kRBj

0k,j11(3.6)0(3.7)

21

3-7 Priority Tables for SerFR

11 10121021122=1

CEURBCCURB

CEU2112

3-4 Flexible Softer Frequency

Reuse SFRSerFR[2]SFRReuse

1Reuse 3Power factortraffic

Reuse 1Reuse 3SoftSerFR

(frequency selective scheduling gain)CCU

CEUreuse1SFRCEU

[3]12=21=0.5SFR

6%sector throughputCEUthroughput32%

RRM(Radio Resource Management)k,jproportional

fairTTICEUCEU throughputFrequency

reuseCEUco subcarrier

PERCEUSINRfrequency reuse

22

SFRSerFR

SerFRSFR

SerFR(sector throughput)

SerFRcell edgeco subcarrierSFR

SFRCEUfrequency reusereuse 3SerFRreuse 1

SerFRFrequency reuse

mC CIUmPRB(Physical Resource Block)

mE CEUmPRB(Physical Resource Block)

mT mPRB(Physical Resource Block)

[7]effective reuse factor eff

EmCm

Tmeff

(3.7)

CEUcellco subcarrierCEU

chunkCCUfrequency

CEUfrequency7cell layout

3-8

3-8 A seven cell hexagonal cell layout

23

cellCEUfrequency3-9SFRCEU

frequency0.5PRBCEU

Transmission BW 10MHz3GPP[4]chunk375

kHz24chunk3-1

Bandwidth (MHz) 1.25 2.5 5.0 10.0 15.0 20.0

Physical resource block

bandwidth (kHz) 375 375 375 375 375 375

Number of available

physical resource blocks 3 6 12 24 36 48

3-1 PRB

effective reuse factor

1.6724

1624

Tm

EmCmeff

3-9

(Distance of Inter eNodeB)

3-8

UserUser

(Flexible)

24

CCUCEUeffective reuse factor eff

CEU mE 3-2 mC

mE (3.7)effective reuse factor eff

3-2 Flexible effective reuse factor

CEUPRB0SFR

8 mE mC 24SerFRCEUcell

PRB3-10Cell 1

Cell 246PRBCell 1Cell 357PRB

subcarriereffective reuse factor

moE PRB

coP

Em

Emoco

(3.8)

25

3-10

eff CEUPRB(3.8)

CEUSINRcellPRB

cell eff 1.33CEUA bandCEU

eff 1.33B bandCEU

A bandA bandPRBPRBCEU

eff 1.33CEUB band

3-11 A band

26

3-11 B band

CEUSINR

27

Maximum C/IRound Robin

Proportional fair[16]SOPF(Subcarrier opportunistic proportional

fair)

4-1 Maximum C/I

throughputSINR

SINRthroughput

SINR(scheduling)

TTICEU

CEU throughput

Round Robin

Maximum C/I

CEUSINR

Proportional fair

Maximum C/I Round Robin

),(R k nt tnsubcarrier

)(Tk t ktsubcarrier n

)(

),(maxarg

tT

ntR

k

k

k

(4.1)

)(Tk t ksubcarrier

28

throughput

t

Subcarrier opportunistic proportional fair

[16]proportional fair

)(

(t)))R-n)(t,(Rn)(t,(R av(n)kkmaxarg

tTkk

(4.2)

)(R av(n) t Ktsubcarrier n

),(R k nt subcarrier nk

throughput

tradeoff

4-2 tradeoffSerFRReuse 1CEU

PRBtradeoffCEUco subcarrier

Frequency Reuseco subcarrier

tradeoff[8]Dynamic Resource

AllocationTwo-Level resource allocation(TLA)

cellular system McellcellN

PRBPRBTTIuTTIPRB nTu, um

uusermcell un uusernPRB

m1Mcellular systemuser uMm m1uM n*m

29

11

2

1

1 muuu

22

2

2

1 muuu

(4.3)

n

m

nn

uuu 21

[8]Major GroupCEUCCUGroupresource

allocation algorithm

Step 1User groupCEU Group U1 CCU Group U2

Step 2PRBCEU

Step 3PRBCCU

3-4frequency reusecellCEU

PRB eff PRBCCUCEU GroupCEU

mappingPRBGroupCCUCEUPRB

(CEUPRB)CEUPRB Group

CCU

Node BAdmission Control()userRRC

ConnectionPRB

SINRSINRmincallBlock

call4-1RRC Connection

30

4-1 RRC Connection

UE(Connected mode)Node BTnSINR

thresholdCEU SINRTnSINRthreshold

reallocatereallocatePRB jn 0

If sinr un sinrmin

un outage count+1

If sinr un sinrthreshold

un = 0

nTu, = 0 (4.4)

End

End

Loop

Forced termination probability P forced

P forced OutagenumumCallsetupnForcenum

(4.5)

31

usercelloutageoutageSINRSINRmin

outage

outageP dadP sf

SINRtn

sfsh

minSINR

-AAS

1 (4.5)

AS cell

sf shadowing factor

sfshP variance 2 sf PDF

2

2

2

22

1

sf

sfsh eP

(4.6)

UE rP multipath

fadingdistance-dependentshadowing

FSRGpAPtxr )( (4.7)

Ptxcell

A

)(RGp eNodeBUER

S

F fading

SINR(4.8)

m

1i(i)(i)(i)(i)

(s)(s)(s)(s)

)(

)(SINR

PnoFSRGpAPtx

FSRGpAPtx (4.8)

(Shannon theorem)userchunk

SINR1logC 2idthchunkbandwtyhunkcapaci (4.9)

uthroughput )(PBS total B

chunk n

32

N

nnunu

U

uIN

B

PI nunu 1,2,

1,

)1(logmax,,

(4.10)

Subject to

nuI nu ,1,0, (4.11)

nunu ,0P , (4.12)

nIu nu

1U

1 , (4.13)

)(1 ,,

U

1 totalBS

N

n nunuuPPI (4.14)

BNsubcarrier nuI , u

nsubcarrier10

subcarrier nu ,P unsubcarrier nu , u

subcarrier nSINRsubcarrier

)(PBS total

33

N

Geometric factor

User group|U1||U2|

PRB (n) Mapping

|U1| for nEm|U2| for nCm

Un.m SINR >

SINR min

Outage

Un.m SINR <

SINR threshold

PRB (n)Searching

SINR PRB (n) >SINR threshold

Y

PRB (n) used N

4-2 Re-allocation

Y

N

Y

Accept

Allocation

34

Subcarrier opportunistic proportional fair addiC

uthroughput01

0proportional fairu

throughput

throughput

(t)R-n)(t,RC av(n)uaddi (4.15)

)(

(t)))R-n)(t,(Rn)(t,(R av(n)uu

tTu

(4.16)

4-3 Subcarrier opportunistic proportional fair

CEUCCUchunk

p

p

CCU

CEU (4.17)

3-2effective reuse factor eff 1.33CCUchunk

35

2

3

1 EmCCUpp

TTp

m

m

(4.18)

mC CIUmPRB mE CEUmPRB mT

mPRBPchunk

36

4-4

PRB (n) Mapping

|U1| for nEm|U2| for nCm

CEU Group

?)(1 ,,U

1 totalBS

N

n nunuuPPI

?1 ,,

U

1 M

N

n mnnuuUuI

Y

Input Data:

User distribution,

call duration

END

CCU Group

Allocate?

)(

(t)))R-n)(t,(Rn)(t,(R av(n)uu

tTu

N

Call

Block

Calculate

CEU throughput

Calculate

CCU throughput

37

MatLab

5-1

5-1-1 19

5-1Node Bcell

cell

user

user1060(step5)

5-1

38

UEcell 18(connected mode)UE

cell 18PRBcellPRBcell 2461014

4-12G

Hz10M Hzchunk375K Hz9M

Hzchunk24

Cellular layout Hexagonal grid, 19BSs

Site-to-site distance 1732 m

Carrier Frequency 2G Hz

Bandwidth 10 MHz

Number of Antennas 1Tx,1Rx

BS/ UE Antenna gain 14 / 0 dBi

Number of chunks 24

Chunk bandwidth 375kHz

Standard deviation 8 dB

Shadowing Lognormal

Modulation QPSK,16QAM, 64QAM

Coding 1/3,1/2,2/3,3/4

Distance-dependent path loss L=128.1+37.6log( R )

UE speed 3 Kmph

0.5

2

5-1

1. subcarrierCIUCEUGeometric factor

CEU3-9subcarrierCIUReuse 1

subcarrier

2. CCUCEUPRB(CEU

PRB)CEUPRB GroupCCU

3. (Shannon theorem)userchunk

(4.9)Ruserchunkthroughputmcell

39

CIU im,k mcellCEU em,k CIUCEU

throughput

k

iiim R

1

,R (5.1)

k

eeem R

1

,R (5.2)

cell throughputCIUCEUthroughput

emimtotalm ,,, RR R (5.2)

5-1-2 UE

)(6.371.128P RLogdBathLoss (5.3) Ruser

5-2

ITU(International Telecommunication Union)

40

(time delay)

(Path-loss)(Multipath fading)

SISO(single-input single-output)ITU Pedestrian B Tap 2

4.8TTISINRGeometric factor

5-2 ITU Multipath fading

5-2

5-2-1 throughputuserchunk

TnSINR 4.9cell60

usercellCCUCEU

CCUCEUSINRTn

SINRCEUSINRSINR minaccess

outagechunkaccessaccess

SINRGeometric factorCCU

3-2 eff 1.501.671.83overall

throughputReuse1Reuse3PFRSFRSerFR

5-3

Reuse 1overall throughput

Reuse 3throughput

41

Proposedoverall throughput eff

SFRSerFR

PFRReuse 3

10

0.5

1

1.5

2

2.5x 10

4 Overall capacity comparison

Reuse Method

K b

ps

Reuse 1

Reuse 3

SFR-alpha=2

PFR-Refa=2

ProFR-Refa=1.50

ProFR-Refa=1.67

ProFR-Refa=1.83

SerFR

5-3

cellcell

useraverage throughput5-4throughput

useruser10355-5Reuse 3

32user()throughput45%

(4.8)Reuse 3Inter cell interference

SINRReuse 3userSINR

usercelluserchunk

user33SerFRthroughputuser

42

41Reuse 1throughputSerFR

PFRReuse 3PFR

CEUchunkSFRSerFR

CEUthroughputSFRSerFR

celluser45throughput

Reuse 3SFR

subcarrier

10 15 20 25 30 35 40 45 50 55 600

0.5

1

1.5

2

2.5x 10

4 usernum vs Throughput

usernum

Th

rou

gh

pu

t

Reuse 1

Reuse 3

SFR-alpha=2

PFR-Refa=2

ProFR-Refa=1.50

ProFR-Refa=1.67

ProFR-Refa=1.83

SerFR

5-4 (10~60)

43

10 15 20 25 30 35

-4000

-2000

0

2000

4000

6000

8000

10000

12000

14000

16000

usernum vs Throughput

usernum

Th

rou

gh

pu

t

Reuse 1

Reuse 3

SFR-alpha=2

PFR-Refa=2

ProFR-Refa=1.50

ProFR-Refa=1.67

ProFR-Refa=1.83

SerFR

5-5 (10~30)

5-2-2 Outage rate Forced termination rate outageReuse 3outage rateuser

PFRSFRReuse 1

Proposed eff mE outage rate

Reuse 3cellchunk

usercellchunkoutageuser

44

10 15 20 25 30 35 40 45 50 55 600

0.1

0.2

0.3

0.4

0.5

0.6

0.7usernum vs Outage rate

usernum

Outa

ge r

ate

Reuse 1

Reuse 3

SFR-alpha=2

PFR-Refa=2

ProFR-Refa=1.50

ProFR-Refa=1.67

ProFR-Refa=1.83

SerFR

5-6 Outage rateuser number

PFRSFRreuse factor1.51.712

5-7outage ratePFRreuse factor

1.5reuse factorcell edge bandCEU

chunkuserPFRoutage rate

SFRoutage rate0.1

45

10 15 20 25 30 35 40 45 50 55 600

0.1

0.2

0.3

0.4

0.5

0.6

0.7usernum vs Outage rate

usernum

outa

ge p

robabili

ty

Reuse 1

Reuse 3

SFR-alpha=2

SFR-alpha=1.71

SFR-alpha=1.5

PFR-Refa=1.5

PFR-Refa=1.71

PFR-Refa=2

5-7 PFRSFROutage rateuser number

5-8Forces termination rateuserReuse 3

terminateuser

chunkRRCPFR

Proposeduser450.01Reuse 3PFR

46

10 15 20 25 30 35 40 45 50 55 600

0.05

0.1

0.15

0.2

0.25

0.3

0.35usernum vs Forced termination rate

usernum

Forc

ed t

erm

ination r

ate

Reuse 1

Reuse 3

SFR-alpha=2

PFR-Refa=2

ProFR-Refa=1.50

ProFR-Refa=1.67

ProFR-Refa=1.83

SerFR

5-8 Forced termination rateuser number

10 15 20 25 30 35 40 45 50 55 600

0.05

0.1

0.15

0.2

0.25

0.3

0.35usernum vs Forced termination rate

usernum

Forc

ed t

erm

ination r

ate

Reuse 1

Reuse 3

SFR-alpha=2

SFR-alpha=1.71

SFR-alpha=1.5

PFR-Refa=1.5

PFR-Refa=1.71

PFR-Refa=2

5-9 PFRSFRForced termination rateuser number

47

PFRSFRreuse factor1.51.712

5-9Forced termination ratePFRreuse

factor2reuse factorcell edge bandCEU

chunkCIUchunkSFR

outage rate0.02

5-2-3 Residual PER HARQ(Hybrid Automatic Repeat reQuest)

3Residual PER(Packet Error Rate)

5-10Residual PERReuse 3PFRcell

edge bandcell center bandResidual

PER5-6Reuse 3 Residual PER

tradeoffoutage rate5-3throughputthroughput

Reuse 3Residual PERcell

throughputoutage rateReuse 1Residual PER

Reuse 1 UserCEUCCU

chunkaccess

cell edgeSerFRSerFRCEUCCU

CEUtransmitted powercell

(4.8)SerFRCEUReuse 1SINR

Residual PER0.40.65SFRSerFR

eff mE CEUchunkusercell

subcarrierResidual PERcell

throughput5-3

48

10 15 20 25 30 35 40 45 50 55 600

0.2

0.4

0.6

0.8

1

1.2

1.4usernum vs Residual PER

usernum

Resid

ual P

ER

Reuse 1

Reuse 3

SFR-alpha=2

PFR-Refa=2

ProFR-Refa=1.50

ProFR-Refa=1.67

ProFR-Refa=1.83

SerFR

5-10 Residual PERuser number

5-2-4 Throughput user

CEUthroughputuser

userSINRCEU

throughputthroughputuser

user5%CEUthroughput85%

CCUthroughput

49

5-11 5th percentilethroughput

5-11CEUthroughputreuse

factor 1.50SerFR3.85%SFR(power

factor=2)11.01%PFR(reuse factor=2)

5.3%Reuse 113.44%Reuse 3

8.50%reuse facto1.671.5%

reuse facto1.832.46%5-3

eff CEUcell edge bandCEU

throughput

Schemes

5th percentile

(Mbps)

ProFR_1.83

Improvement(%)

ProFR_1.67

Improvement(%)

ProFR_1.50

Improvement(%)

Reuse 1 4.1021 10.73% 11.77% 13.44%

Reuse 3 4.2890 5.90% 6.90% 8.50%

SFR,power factor = 2 4.1919 8.35% 9.38% 11.01%

PFR,reuse factor = 2 4.4192 2.78% 3.75% 5.30%

ProFR,reuse factor = 1.50 4.6536 -2.40% -1.47% 0.00%

ProFR,reuse factor = 1.67 4.5849 -0.94% 0.00% 1.50%

ProFR,reuse factor = 1.83 4.5420 0.00% 0.94% 2.46%

SerFR( 12 =21 =0.50 ) 4.4811 1.36% 2.32% 3.85%

5-3 CEUProposed FRFR

50

5-12CCUthroughputReuse 3CCU throughput

PFRreuse factor 1.83

SerFR(12=21=0.5)-0.09%Reuse 1

-1.30%Reuse 35.85%SFR(power factor=2)

0.3%PFR(reuse factor=2)5.09%

reuse factor 1.67SerFR(12=21=0.5)

-0.14%reuse factor 1.50 SerFR(12=21=0.5)

-0.61%5-4


Schemes

85th percentile

(Mbps)

ProFR_1.83

Improvement(%)

ProFR_1.67

Improvement(%)

ProFR_1.50

Improvement(%)

Reuse 1 8.0031 -1.30% -1.34% -1.80%

Reuse 3 7.4626 5.85% 5.81% 5.31%

SFR,power factor = 2 7.8758 0.30% 0.25% -0.22%

PFR,reuse factor = 2 7.5168 5.09% 5.04% 4.55%

ProFR,reuse factor = 1.50 7.8587 0.52% 0.47% 0.00%

ProFR,reuse factor = 1.67 7.8958 0.05% 0.00% -0.47%

ProFR,reuse factor = 1.83 7.8994 0.00% -0.04% -0.52%

SerFR( 12 =21 =0.50 ) 7.9069 -0.09% -0.14% -0.61% 5-4 CCUProposed FRFR

51

5-115-12 eff

CEU throughputCCUcell throughput

reuse factor1.50SerFRCEU throughput

3.85%cell throughput12.03%CCU throughput0.61%

SFRCEU throughput11.01%cell throughput

4.73%CCU0.22%

reuse factor 1.5CEU throughput

throughputCEUCCU

Subcarrier opportunistic proportional fair

addiC CCU throughput

5-14


52


CEUCCU CEU

throughputCCUOverall throughput

5-15 5th 85th percentilethroughput

53

10

0.5

1

1.5

2

2.5x 10

4 alpha VS Overall capacity

alpha value

K b

ps

alpha=1.67

alpha=2

alpha=2.5

5-16 Overall throughput

54

(Dynamic Resource Allocation)

OFDMACEU

throughputreuse factor eff CEUCCU

throughputResidual PER

userreuse factor

end userthroughputoutage rateResidual PER

CCUCEU throughputtradeoff

CEUthroughput

3GPPthroughput

Femto

Femto AP

(Hierarchical Cell

Structure)

Macro cell Micro cellFemto cellRRM

55

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