lEE亡TRA､NSACrl0NSONVEHlCULARTECHNOLOGYVOL48NOLJANUARYl999

Co汀elationBandwidthCharacteristicsfわrPaths

BetweenBaseStationandBuildingRoofsShln'lChrchltsubo,AklraAkeyama.andShuJISakagaml

AbsdacE-Correlation(Coherence)bandwidthsforthepathsbe-tweenbaseslationandbtJjJdlngroofantennaswereobtalnedfromtheampLittlde･frequeJICyCharacLeristiesmeasuredonther00rsoH lbui)dlngSinTokyo,Japan,inthe900･MfTzband.FortJlecaseswherethebase-stationanteltnaWasinJine10トslgtltfrom(hcbulLdlTLgr00fantennaandthepropagallOnlosswas2-9dlilargerthanthefree-spacepropagatIOnloss,thecorrelatlOnbandwldthdecreasedastheexcesslossfrom rree･spacepropilgat)Onlossincreased･Forout-of-slghtcases,correlationbaTldwidthsraf)監edFrom38to320klIzandweresimi一artothoseestlmatedforon

road.ThecorreJat10nbandwjdlhmeasuredusmga12-elementYaglarLteTlnaWasdoublethatmeasuredwithahalf-wavedIPOleantertna.

Ⅰ INTRODUCTION

R :,ceEd慧 慧 adligTaFzs'.egcneal..LUnTscshy;:Tssr::e.ie_ebnand.evaen)i

w]de-band tlme-dlVISionmultIPleaccess(TDMA)]formoblle

radlosystems lndlgltalmobllecellularsystems,muIllPath

de)ayllmtStheperformaJICeOfd】gltalslgna】LransmlSSIOn

TodeslgndlgltaJmobllecellularsystems,multlpathdelay

charactenstlCSOrCOrTelat10n (COherence)bandwldthshave

beenmeasuredonpathsbetweenbasestaUonsandmoblle

vehlC)esonroadsll]110]

However,multlPathdelaycharactenst]Cshavenotbeen

clanfiedsufficlentlyforvar]ouspropagationCOndlt10nSFor

exarnple,1日SnotClearhowmultlPathpropagationChaTaCtenS-

tlCSChangeasthemobllerecelVlngSltemovesfromtheground

tohlBherposltLOnSOnbu)ldlngroofsThesechaTaCtenStICSate

usefulforclarifylngthemulLIPathpropagat10mmeChanlSm tnurbanareas

LnordertoclaTlfythemulttPathpropaga【10nmechanismOn

pathsbetweenthebasesta110nandbulJdlngroofs,Wemeasured

山eamplltUde-frequencycharactenStlCSlnthefrequencyband

from 915to920MHzonpathsbetweenabasestatlOnand

bulldlngroofsThlSPaperPresentstyPICaJexamplesofthe

measuredamplltude-frequencychaTaCtenSt]CS,therelationshlP

betweenthecorTelatlOnbaLldwldth and theexcesstosses,

compansonsofco汀elatlOnbandwldthsmeasuredonroofsto

thoseestlmatedforonroad,andthere]atlOnShlPSbetweenthecorTelauOnbaLldwldthand3-dBbeamwldthofthemoblle

recelVlngantenr)a

TherearefewreportsoncorT'elattonbandwldth,OrmultlPath

propagatlOnOnpathsbetweenthebasestatlOnandbulLdlng

ManLISCnPtreCelVedApn17.L996,revISedJanuary22J997SIchltSUtX)1SW】LhtheWITdessCommunlCat10nSystemsLabora10neS

m .JapaLIAAkeyamatswILhELleNTTAdvancedTechnologyCorporatlonJapanSSakagamllSWILhHokbldolnforTnatlOnUmverslty,Hokkaldo069,

JapanPubllSherItemldentlflerS0018-9545(99)(氾720-3

ANT ANT

Transmltler Rec

eNerF唱 1 Bl∝kdlagramOfmeasurementsystem

TABLEIMEASUREMErTrFE〟rU

RESFrequency

91ト920ullSTeeP5te【l 9.7klL

zsTeePYe)0Ly

Z仙1エ/ILinpOYer8asesLali anLenFlaEhsesLaLi

rourLdea87maboveLhe

earllennaar)tenr)aalllennaTCCeiveT

OdBFLroofsTherefore,thisPaperElvesgoodh

mtsforclanfylngthemultlPaLhpropagatJOnmeChanlSmS

Lnurbanareasll_DESCRIFT10NOFMEASUREMENT

SA MeasuremenlsofAmpLLtLLde-FrequencyCharacTenSTECSln t

hlS eXpenment,amPlltude-frequency chaTaClerlStlCSwere

measuredbysweeplngaCOntlnuOuSWavefrom 915to920MHzlnS

tepsOf9-7ktlzbycontrolllngaSynthes]zerwl【hade

sktopcomputerl=lg lshowsablockdlagram Ofthemeas

urementsystem,andTableIshowsmeasurementfeaturesThe frequency-Sweptslgna)(vertlCa】polanzation)wastransm】tted from a base-stauon antenna (o

LEEヒTIW SACTIONSONVEHICULARTECHNOLOGY〉OL4%NOIJANUARYl999

bldB_naJLeheigrLldisl.I

tIldL1 SF J_6h Yes lOJ.Jt

dFl 8_6d且bLd8.2 5F 2,Ok■ Yes

lOJI.OdtL 6.3dBbldL3 JOY 2.7k

J Yes lO2.6d8 2_6JBbldL4 4

P 3_Ok■ YES 8_3dElLIIJg.5 8F つ+ILL No. ]24.1d8 22_l

d8bl叱 6 8P 3_Gh No. Jl5_2dB

l2_4dE)bldg.7 JF 4_2kb 〃○_ 19.

9dⅠ1bld8.8 7F 4_3ltJL rh

L12_Odl一 27.7d【IbldR.9 tip 4

_5k■ No_ )2l.GdrL ]6.8d8bldg,10 6P 4.6b Ho_ 柑_4dEl

b[JLH 7P 5.JkJ 恥 . J27.4dカ 21_6dB暮dlSLMICeTrotbaseSLatl

0nIIprol)ataLIOnJossobLJIItedrrLLLaJPhLIJdeJrcqdellCyCharJClerlStLCSIIIpropiEall0爪loss-rTeeSpacePrOP

agaLIOq事osscorporaL]On),thefrequency-sweptslgnalw

asrecelVedusuaHybyahalf-wavedlpOleantennaandafie)d

strengthmetercontrol)edbyadesktopCOmPuter.Rec

eLVedslgnalampllLudedatawere recorded on cartndge tapes

Each amplltude-frequencychaTacterlSt)CCOnSistedof512amplltudevaluesw】t

ha97-kflzlmerVal.iMeasurementsweremadeontheroofso

f11bulldlngswhlChwereupto5kmfromthebaseslal10n

inTokyo Bulld一lngsselectedasmeasureTTlentSlleSWere

Chosenasfollowsl)DIStanCefrom basestationTTluStbe

wlthlnabout5kmtomakethedynamicrangeoftherece]vedslgnalleveIsufRc】entforout-or-s

lghtmeasurements2)BU)ldlngSneednotbesohlgh,corn

paredLothebase-statlOnantennaheLght(57mabove

theground)becausevanousdegreesoHLne10f-S]ghtpropa

gatlonareneeded3)Thebut)dingroofmustallowtheequ]pme

TlttObesetTabknnotesthefeaturesofrecelVIngSites.su

chasbul】d-1nghe)ght(numberoff一oors),dlSlanCefromth

ebaseslatlOn,]lne-Of-szghtornot,andpropagatlOn一o

ss Propagat]OnLosswasobtalnedfrom theaveragevalue(compute

dinantHogvalue,notindecibels)ofTeCelVedslgnalleve

lasseenlntheamplltude-frequencycharactenstlClnthe5-

MHzbandExcesslosswasoblalnedasthedl打erencebetweenpropaga110nJos

sandfree-SpaceprOPagatlOn一ossExcesstossesarealso

llStedlnTableIIMostbuitdlngroofsusedforourmeasur

emenlSWereen-c一osedbyawIIe-netflenCe lnordertofindthea

mplitude-frequencycha,ac(erist)cswllhou(wlreneteffects･t

hereceIVlngaJltennaWasSetOnStnJC【uressuchascoo】lng

LowersSOaStOe)lmlnatetheshit)dlngbythewlre-net

fenceMeasurementsweremadetwoumesbymovlngtherecelVIng

antennaabout30cm(onewavelength)onthestructureonthe

bulldlngroofwhenr)(lsslbleWhentherewasnofenceonthebulldlngroof,measuremenlSWeremadethree

t】meS.mOVlngtherecetv】ngantennaabout30cm(onewa

ve)englh)eachtlmeYag)antennasw)th8and 12elementswereusedasthe

rece)VlngantennasOn t

桓(LLLtjP)rO^

OIPa1

8a∝

Frequency(MHz)

(a)

(iV)d

u

olteI

aJ

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FreqLLenCySeParat10nAf(MHz)

(b)

Flg3 Examp)esofampIJtudc-frequencycharaelensIICSandfrequencycoトrelaLzOnP(△I)(a)Ampl机.de･frequerLCyChaTaeLenStlCS(b)Envelopecorre-tat10nP(△J)

-40

(d) -7

0-

100915 920FIB4 Examplesolamplltude-frequer)cycharactensLICSforllne-Of-slghtpropaga110nPatLl(a)Llne-Of-slghtcasewllhlargeClearance(♭)CntlCal

I)ne･of-S唱hlcase(C)Mor

ecntlCaHlne･Of-S唱htcase(d)L】rLe-Or-Slghtthroughw trenetaresmallnppleslnaJnPlttude-frequencycharactenstlCSFromthe

excesslossvaluesofthesethreecases,ltCanbesaJdthatdelayedwaveswlth smauamplitudeappearattherecelVLng 望4

｡70(uJ皿P)1a心一POfG)3atj -40(d) イ0-100915 920FIB5 Exarnplesoramplllude･rrcquen

cycharactensLICSforout-of-slgh【propagal10nPath(a)LJne-Of-slghllSObstructedbybulldlngS farfromre-rrOmre-moved30celYlr)g

POlnt(b)Samecaseasabovebutrecelvlnga爪Lertnawascm(C)Llne-Of-51ghLISObs(rlJCtedbynearbylaTgebulldLJlgS(d)Sa

mecaseasabo ve.butreCelVlllganteTmaWasrnOVedlmaTLtenna,

aSthedlreCtWaveSuffersSmallattenuatlOnFlg4(d)show

sabasellnemeaSuremenHhEOughthewLre-netfenceontheroof

ofbulldlng4Theaverages】gnal]evellnthe51MHzbandlSab

out10dBlowerthanthatlnFig4(C),andnpplesare)ar

gerthanthoselnFIB4(C),duetotheshleldlngeffectofthew

irenetTheradioChannelswerestableand

didnotshowanytunevarlat10nThlSISduetothefact

thattherecelV]ngPOlntSWereonbulldlngroofs.Itseemsthatwavesscatteredorreaec【edfrom vehiclesaresuffic

ientlyattenuatedatthebulldtngrooflevel2)Out-of-SLgh

tCase-Flg 5(a)and(b)Showsexamplesofthemeasuredamp

lltUde-frequencycharacLenstLCSforbulldlng5(elghtfloors)Fortheouトof-sLghtcase,theLlnel0f-slghtwasobsm ct

edbybulldlngSHowever,uptoseveralhundredmetersfro

mtherecelVlngPOlnt,therewerenobulldlngShigherthanb

tEEETRANSACnONSONVEHtCULARTECHNOLOGYVOL4%NOIJANUARY)999

0

0

0

0

0

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9

6

3

人Z王

).A

.quO竜一OJJ00

0 5 10Excesslossfromfreespacepropa

galionloss(dB)F)A6 Relatl0nShlPtXtWeenCOrTelaLlOnbandwldthandexcesslossfTOTT)free･SpacepropagaLJOJIlossonb

ulldlngloors(Ilne-Or-STght亡aSe)valuesaTnVedaHhereceivln

gantennaslnce山erewerenohlghbujldl

ngSaroundthereceJVlngPOlnt.Flg5(C)and (d)shows exam

ples orthe nleaSuredamp]ltude-frequency chaTaCtenSt]CS

forbut)dlng 8 (sevenfloors)fortheouトOf-slghLCase Th

erece)vlngPOlnLwassurrounded by htgh bulldJngS

,SO the )lne-Of-slghtwascompleleJyobsITllC【ed_Excesslosswasabout2

8dBTheamplltude-frequencycharaclehstjc)nFlg5(C)]ss)m)-

1arto山alinFlg5(d),whlchwasmeasuredaftermoving

山erecelV)ngaJltenna)m szdewaysR]ppleswlthIongpeTIOds

aleSeenlnbolh伝guresTheaveragepath-一engthdlffere

ncebetweendirectWaveaJlddelayedwaveslsestlmatedto

beabout6(泊 m (2JJSdelay)Orlessfrom theaveragenpplepenodlnFig.5(C)and(d).Ttseemsthatmu一tiplewaves

wlthlongdelaydldnotaTrjveattherecelVlngantennadue

tothesuJTOundlnghlgh bulldlngs8 CorreLotJOnBondwLdt

hCorTelatjonbandwldth)SoneofthemeasureswlthwhlCh

wecanevaluatedlg)La]SlgnallraT)SmlSSioncapaclty)nmuI

叩alhenvironmentsl2],[3],[JI] TnlhISPaper,thefreque

ncysepara110na(WhJChtheenvelope corTelatloncoefRclent)s

05lSChosenasthecorre)at10nbandw】dLh.asmenl10nedlnSecLJOntIIB ThecorrelaL)OnbandwldthlSObtainedfroman

amplltt)de-frequencychaTaCterisucbyusmg(1)･))LJne-0/-SLg/zTCase･General)y,itlSexpectedthatthecorTe)aLlon

bandwidLhforllne-Of-slghtpathstendstodecreasewl山 lnCreaS

lngarlenuatlOnOrthedlreClwavebecause山ere)atlVeamPll

njdesofmu)tlPLewaveswithlargede)aybecome)atgeasthedlTeCtWaveattenu

atesDLreCtWaveattenual10nlSrelatedtoexcesslosswhich

meansrecelVeds)gnaHeve)atten-uatjonfromthefree-spac

elevelforllne-Of-S)ghtpropagationFlg.6Showsthere)atLOnShlPbetweencorTe)atlOnbaJldwldthandexcesslossT

henumberofdatalnFIg6ISSma)Ibecauseofthedlf鮎ul

rylnCOnduc【lngmeaSUremenlSOnmanybulld-1ngroofsHoweve

r.ltSeemsthaHhecorTelat10nbandwldthdo郎 dependontheexc

esslossAn)ncreaselnexcesslosscorrespondstoanlnCreaSelndlreCtWaveaLlenuatlOnThlsatlenuationcausesanIncreasein山ere)atlveamp)ltUdeof multlplewavesreflecLed､scattered.ord

)fFractedfrom theupperpaJISOfbul)d]ngs2)Out-of-SLgh1-ccseIForout-of-stgh(cases,ltlSanlnter-estlngqueSt10naStOWhetherornotcorTelal10nbandwldlhsrrLeasuredonbul

ldlngTOOfsarelargerthanthoseforonroadHowever.nodala

ro√lhlSWasrecordedAnernplncaJfomulaforesLJrnallngthecorTe)atlOnbaJld-w

∧U

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EstJrrLateSlo10n-roado measuredonbulklLn9rCOIs

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hb=創m

2 3 4 5 6

Distancefrombasestat10n(km)

lユl

(ZHq)･Md

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2 3 4 5 6Distancefrombasestation(km)(b)Flg7 CorrelaL10rLbandwJdlh(aW)measuredonbuLldlngroofscompaLredtothoseesllmatedforonroad(ouトOf-slghtcase)(a)Forbase･SLaLlOtlar-(ennaheightfrom47to6lm (b)Forbase-sLaLJOnaJltennaheLghtrrorn77to84m

ZLisexpectedfrom Flg7(a)and(b)thattheexLenLorthe

scattenngareaproducingmulllplewavesforon-roofmeasure-mentsisnotsodlfferentfromLhalforOn-roadmeasure

men【slnthecaseofout-of-sLghtpropagatlon.mu)tIPlewaves

aLmVeaLthebulldJngroofSuffenngreLlectlOnOrdlffra

cL10mfrom otherbulJdingsNext,tJleSeWavesamVeaHheroa

dssuFFenngdlffracttonbytheedgeofthebulldlngroofarLdreflectlOnfromnelghborlngbuL]dlngSTherefore,lLSeemsthat

muLllPathdelaysatthebutld)ngroofarecomparabletoth

oseatroadlevelThlSmeChanlSm explainsWhythecoTTe)al10nbandwtdthvaluesonbuildlngroofsarecomparableto山ose

onroadsC CoTreLatLOnBandw,dt/zwtLhDLreCtio/ialAn

tennaJtwasreportedthaHhecoTTelatlOnbandwld山 lnCreaSeSaS

山ehearnwldthdecreaseslntheihorlZOntaJplaneformo

blleantennasonroadsl811norderloclari中 山edependenceofcorrelatjonbaJldwldthonantennat妃am WldthonbuiJdl

ngroofs,CorTelamonbandwlddlSWeremeasuredatonepoint

Ontheroofofbuildlng6,usingt山eeantennaswlthdlfferent

dlreCtlVl【yahalf-wavedlPOleantenna,ane1ght-elementYa

g]antenna,anda121eJemenLTag)a

ntenJla_Llne-Of･slghlWasobstmcledbybulldlngSOnthe

pathF)g8showstherelal)onshlPbetweencorrelatLOnb

and-wldLhsandthe31dB beam wLdthsofthethreedu-ectIOnalarLtennaS,alongw)th山eon-roadresultsl8】.CorTe)atlOnband-

wldthsarenorTnallZedbythatmeasuredbyahalf-wavedLPOleantennaTheresultsforOnrOOfaTeSlmtartOthoseforonlo

ad,andthecorrelationbaJldwldthmeasuredbythe12-elem

entYagiantennalSaboutdoublethatofthehalf-wavedlPOleantenna,both Foron-roadandon-roofca

ses.Thjsimprovementappears【Otk Causedbytflereduct

ionlntheamplittJdeofthemuLtlP]ewavesThereductiorL

lnrnultiplewaveamplltudecanbeconhrTT)edlndlreCtlyfromthefactLhaltherecelVedleve)VanatlOnS(staJldaTddev

】alionq)with)na5-MHzbandforthe12-elementYaglantenn

aaleSma)lerthanthoseforthehalf-wavedlPOleanten

na,asshowntnFlg9MeasurementsweretakentwICebymovlngtherecelVlngPOSlhonabout1m sldeways

ontheroofofthesamebulldlng

2

LJtP!AtPueq

uOl】elaJL00PaZllE'uuON

oo1808360

3dBBeanwldth(deg.)

Flg8Re lauonofcorrelaLJOnbaJldw】dlhand3-dBbca JnWldtholmobllereceIYIngantennaforonroadalldonrtx)【

euualue

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eceivedlevelvariatJOnSe (d8)forhalf-wavedlPOIeantennaFIE9Rece)vedlevelyaLmLJOnSWlthlna5-MHヱbandfortheha一f-waved)pcLcaJllennaCOrnParCdtothosefortheL2-clcrncnlYa名川nLema

TheresultshowninFIB.81nd】catestheposslbl)ltleSOf

reduclngmultlPlewavesaJldlnCTeaStngdlgltalslgnaltrans-

mlSStOnratebyuslngdirectIOnalaJltennaS･ThereductionlnmultlPathefFec【sduetoantennadlreCtlVltyWa

IEEETTLANSACnONSONVEMCUuRTECHNOLOGY,〉OL48NO IJANUARY1999

rV.CoNCLUSTON

AmpllLude-frequencychaTaCter]StlCSWeremeasuredonthe

roofsoH 1bulldlngS)∩mull]palhenvlrOnmenlSInTokyo

by sweeplng COntlnuOUSWavesfrom 915 10 920 MHzln

9･7-kJIzstepsTlleenVelope correJatJOnWasCalculatedfrom

the amplltude-Frequency chaTaCtenSl】C, aT)d the corre)aLLOn

bandwLdthwasoblalnedfrom there)allonshjpbetweenenve-

lopecorTe)ationandfrequencyseparalion-MeasurementsweremadeforvanouscleamncecondlLIOnS

betweenbase-slat]OnantennaandbuLldlngroofs Usually,a

half-wavedlPOleantennawasusedastherecelVlngantenna

Ononebu)ldlngroof,elght-aLld 121eJementYag)arllennas

werealsousedtolnVeStlgatetJleeffec10fantennabeam wldLhoncoTTelatlOnbandwldth

ThelmPOrtaJlHeSultsobtalnedfrom theon-roofmeasure一

menLSaleaSflOl)ows

1)Forline-of-sightcasesWl山 propagadon tossesof2

to9 dB largerthanthe free-spacepropagation loss,lhecorrelatzonbaJldwlddldecreasesastheexcessloss

1nCreaSeS

2)Foroul10f-sightcaseswherePrOPagatIOnlosseswere12

1030dBlargerthanthefree-spacepropagatlOnloss,the

corTelaLlOnbandwldthrangedfrom 38to320kHz

3)Forout-oトslghtcases.corTelat]Onbandwldthsmeasuredonroofsareslmllarto山oseesumatedforon-roadcases

lnmUltlPathenvlrOnTnentS

4)Con'elatlOn bandwldth caJlbe Increased by uslng a

moblk recelVlngantennathathasanaJTOW beaLnlnthe

honzontaJp]aJle Thecorrelat】onbandwldth measured

bya12-elementYaglantennaWasdouble山almeasured

byahalf-wavedTPOleanIenna A s)rnllaTresultlSSeenlnOnイOadcases

TheseresuJISarebasedonarelatlVelysrnalIamountof

data.duetothedl用culLyorconducungexpenmentsonmany

build)ngsroofsHowever,ltCanbeexpectedthattheseresults

do provLdeusefullnformaLIOn forclarlfylng the mu)tlPath

propagatlOnmeChanlSm andforsuggestlngpropaga110nChar-

ac【ensLLCImprovements,Suchasmull)Plc-waveTeducl】OnOr

dlVerSltyreCePL]onbydZrecllonaJaTltennaS

ACKNOWLEDGMENT

Theauthorswou一dllketothan上 DrHatLon,DITeCtOrOf

theWlrelessCommunicatlOnSystemsLaboratory)∩NIrT.and

DrKawasakl.GroupLeaderoftheWlrelessCommunlCat)On

SystemsLaboratory forthetrusefulsuggest]ons

REFERENCES

ll)D CCon'●DISLTlbutl0nOfmultJPathdelayspreadandaverageexcessdelayTor910-MHzurbaLlmObllcradl0Path:'/EECTran∫AnLennaSPn?pogGl.VOIAP-23pp2061213.1975

r2】D C Colar)d氏 良 Leek."CorrelatlonbandwldLhanddelayspreadrrLultlPathpropa呈attOnSLatlStlCSrot910-MHzurbanrnoblteradIOChan･ncls/lEEETrDnSCo'TmZLLn.VOICOM-23.no H.pp 127ト1280,】975

T3]A SBa)waand∫D Parsons.lSrnal1-ueachaTaClen乙atIOnOfUHFurbanandsuburbanmoblleradlOPrOPagatl0n P仰ぐJ173tI/ectEng.vol129ptドno 2,pplO2-109 1982

[4】- I-LargeareaChanlcten乙aLIOnOfurbanUHFmu一l)pal九pTOPa-gat10nandltSrelevancelotheTXrform aLlCe tX)Undsofrnoblleradl0systems/'PTDCInsIEle亡tEng,vol132pLF.no2pp991106,1985

【5】PMelanconandJLEel.--AchaTaCtenZatJOnOfthefreqLJenCySelectJVefadJngOfthemobl】eradJOChJlnd-1EEfTro75 Veh.TecJzhOJVOJ35pp 153-16L.)986

16)A MatlhewsandD Molk血 ,l▲WidebandncasurcmenLSOftk UtlFmoblleradl0ChaTlnC]/tinIEECo'lf(/C4PJRef5C,1987pp73-76

r7JJーVRees.MeaSUre汀叱ntSOfthew)deIbaJldJldlOChalmelchancLCnS･LICSforrllT7LLrcsldenual andsuburbaJlaTejLS,JEEETmnsVth_TechIlOLyo136.pp2-i.)987

L8】SSakagaml"ExpcnmentalresullSOr日TluI叩aLhI)TOpagalIOnln900

MHZmObllecommurllCaLlOnpaul-ATTLP)llude-frequencychaTaCtenSuCSandansteofamval/.TrLZnSlnslElectronh/om Comm Engrs.vo】J70-B一日,no12､pp1522-】528.I987

(91SSakagaLrn]aJldA Akeyama,▲CorrelatLOnbandwldlhlnurbanmobllerad10Paths-DeFkndenceofdlstancc.basestatlOnantennahelghL andavcragebuLldlnghelghL●Tra,LS/nBII/EぐrnI'ZI'Z/o′m Comm EngrS.voIJ74-B-u.pp2ふ-34.1991

日0】E S Sousa,V M JovanovlC andC Dalgneault"Iklayspreadm easuremenlsfcqthedlgltaJcellulaTChaTnelinToronto/.IEEETrolIJVeJITechnoL,vo)43.pp837-S47.1994

lll1W C 一akesJr.〟lCTOttaVe lobL/CConlmLLnLCOtIOnS New YortーWIIey 1974

Shln'】ehJcllltSubowasboTlllnKagoshlrnaJapaTl,IrLa963HereccIVedtheMSdegreefromKyushuUnlVCrSl【yJapanm1988HeJolnedtheRadloComrmnlca110rLSystems

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