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for CommunicationNetworks

Fundamentals of Radio Network Planning

Objectives

The participant is able to

explain the basic steps during radio network planning

Contents

1 Mobile Radio Network Planning Tasks1.1 Collection of Basic Planning Data1. Terrain Data !c"uisition1.# Coarse Co$erage Prediction1.% Network Con&guration

1.' (ite (election1.) *ield Measure+ents1., Tool Tuning1.- Network Design1. Data Base /ngineering1.10 Perfor+ance /$aluation and pti+i2ation

Repetition

# Radio 3a$e Propagation#.1 Path 4oss

#. (hadowing 5 4ong Ter+ *ading#.# Multi Path Propagation 5 (hort Ter+ *ading#.% Maxi+u+ Path 4oss and 4ink Budget

% Cellular Networks and *re"uenc6 !llocation

' Tra7c Models

) /xercises

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Objectives of Radio Network Planning

To provide service

to +an6 subscribers with high ser$ice "ualit6 at low costs

Capacit6 for a tra7c +odel

ser$ice t6pes

call rate

+obilit6

9ualit6 of ser$ice

low blocking

low wait ti+e

high speech "ualit6

low call drop rate

/7cienc6

low nu+ber of B( sites

high fre"uenc6 re5use

Boundary conditions

Pysics! fre"uenc6 spectru+: radio propagation co$erage ; fre"uenc6 planning

"ystem! recei$er characteristics: trans+it power

channel configuration

cell design & network structure

link quality improvement

focal point of this course !

algorithms and parameter setting

*ig. 1

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!s shown in the &gure below: the +ain topic of this course is ad as part of the radio networkplanning process.

Before going into the details of the s6ste+ features and control para+eters: thisintroduction chapter su++ari2es so+e basics on radio network planning?

@n the &rst and second section of this chapter the steps within the radio networkplanning process are explained. @n sections # 5 ' si+ple +odels concerning radiopropagation: fre"uenc6 re5use and teletra7c are presented.

!s each +odel the6 are onl6 an approxi+ation of realit6. Ne$ertheless

the6 reAect the +ain ph6sical eects:

the6 help to understand the +eaning of para+eters and the wa6 of working thealgorith+s:

the6 allow to esti+ate para+eter $alues.

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# $obile Radio Network Planning Tasks

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The +obile radio network is the connecting ele+ent between the +obile telephoneusers and the &xed network.

@n this network the base transceiver station e%uipment=BT(/> is the direct interfaceto the subscriber. @t has to +ake radio co++unication channels a$ailable to the usersand to care for a satisfactor6 signal "ualit6 within a certain area around the base station.This area +a6 be split into dierent sectors =cells> which belong to one BT(/.

Planning a +obile radio network is a co+plex task: because radio propagation along theearth surface is sub+itted to +an6 inAuences due to the local en$iron+ent. *urther+orethe perfor+ance re"uire+ents to a radio network co$er a wide &eld of applicationswhich depend on the operators potentialities and goals. To respond to all these sub.

The network ele+ents de&ned up to this +o+ent ha$e been found on a +ore or lesstheoretical basis. Now it has to be checked if the en$isaged radio site locations +a6

reall6 be kept. ! site sur$e6 ca+paign in accordance with the custo+er: who isresponsible for the site ac"uisition: +ust clarif6 all proble+s concerning theinfrastructure and technical as well as &nancial issues of the BT(/ i+ple+entation.@nside a tolerable search area the opti+u+ site +eeting all these issues has to beselected.

This site selectionshould also take into account particular properties of the area: e.g.big obstacles which are not recogni2able in the digital +aps.

Field measurements: to be carried out in t6pical and in co+plex areas +ust gi$edetailed infor+ations about the radio characteristics of the planning region. The+easure+ent results will then help to align the radio prediction tool for the actual t6pe

of land usage =tool tuning>.

Now: &xed site positions and an area5adapted tool being a$ailable: it is possible to startthe detailed radio planning. The &nal network designhas to care for both su7cientco$erage and proper radio fre"uenc6 assign+ent in respecting the tra7c load and theinterference re"uire+ents.

The last planning step is the generation of a set of control parameters: necessar6 to+aintain a co++unication while a subscriber is +o$ing around. These para+eters ha$eto co+pl6 with the existing cell structure and the needs to handle the tra7c loadexpected in each cell.

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!fter co++issioning of the network: the perfor+ance +ust be checked b6 the networkoperator b6 e$aluation of statistical data collected in the operation and +aintenancecenter. (ituations of congestion or fre"uent call re

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#'# Collection of Basic Planning (ata

The re"uire+ents of the network operator concerning tra7c load and ser$ice areaextension are basic data for the design of a +obile network . ! coarse network structureco+pl6ing with these re"uire+ents can be created on this basis.

Two funda+ental cell t6pes are possible their properties +a6 be deter+ined

a> b6 the +axi+u+ radio range of the in$ol$ed transcei$er stations and +obileter+inals the range is li+ited b6 the a$ailable trans+it power and the noise &gure ofthe recei$ers. This t6pe is called a noise li+ited cell it is t6pical for rural regions.

b> or it +a6 be deter+ined b6 the li+ited tra7c capacit6 of a cell in the case of highsubscriber concentration. This leads to the i+ple+entation of s+all cells: +ainl6 inurban areas where interference will beco+e the +a

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#'+ Coarse Coverage Prediction

n the basis of the digital terrain data base and b6 using standard propagation +odels:

which ha$e been preselected to &t for special terrain t6pes: it is possible to +ake &eldstrength predictions without ha$ing a $er6 detailed knowledge of the particular localconditions.

B6 $ariation and +odi&cation of the site positions and antenna orientations: co$eragepredictions of rather good "ualit6 +a6 be attained.

Fet: the de&niti$e site locations are sub

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#'. "ite "election

The site positions found in the coarse planning process on a theoretical basis: +ust now

be $eri&ed in a ha$e also to be regarded. Thebest &tting site should be selected.

!nother i+portant task of this ca+paign is to declare a certain nu+ber of the radio sitesbe suitable to ser$e as Hsur$e6 sitesG. This +eans that radio &eld +easure+ents shall bedone with these stations as trans+itters. The resulting +easure+ents will be used forthe align+ent of radio propagation +odels.

The en$iron+ent of the sur$e6 sites should be t6pical for a considerable nu+ber of otherradio sites.

#'/ Field $easurements

Digital terrain data bases =DTDB> as deri$ed fro+ topographical +aps or satellite

pictures do not contain all details and particularities of the existing en$iron+ent./speciall6 in fast de$eloping urban areas +aps cannot keep pace with realit6 and thusreAect an obsolete status. Ieeping +aps on this "ualit6 le$el would be $er6 expensi$e.

The characteristics of built up 2ones and $egetation areas with respect to radiopropagation dier in a wide range if we regard dierent countries. /$en cli+aticconditions +a6 inAuence the signal le$el. Inowledge about this speci&c beha$ior +ustbe ac"uired b6 +easure+ents.

The sur$e6 +easure+ents ha$e to be carried out in t6pical areas. /$aluation of these+easure+ents will result in +odels that can be applied in co+parable areas as well.

(pecial +easure+ents +ust be carried out in $er6 co+plex topographical regions where

standardi2ed propagation +odels will fail. The resulting +odels are $alid exclusi$el6 forthis +easure+ent 2one.

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#'0 Tool Tuning

The +easure+ent results ha$e to be co+pared with the predictions of pro$en standard

+odels. The standard para+eters will be slightl6 +odi&ed to achie$e +ini+u+discrepancies with the +easure+ents: i.e. to keep the +ean error and r+s5error as lowas possible. !s the signal le$el is sub

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#'2 (ata Base 3ngineering

! cellular network is a li$ing s6ste+ with +o$ing subscribers. The ser$ice +ust be

+aintained while +obiles change radio cells and superior organi2ation units: calledlocation areas. !ll control para+eters: necessar6 to support this task: ha$e to bead+inistered and super$ised in central data bases.

There is a per+anent signaling infor+ation exchange between +obiles: base stationsand control centers.

This signaling co++unication occurs on prede&ned ti+e slots: called control channelswhich are assigned to one of the R*5carriers of each radio cell.

@+portant control infor+ations for each radio cell are ?

cell identi&cation within the network

control carrier fre"uenc6

potential neighbor cells

+ini+u+ recei$ed signal le$el

+axi+u+ trans+it power of a +obile

power reduction factor to perfor+ power control

power +argin for hando$er to neighbor cells

#'#4 Performance 3valuation and Optimi&ation

Regular perfor+ance checks +ust be carried out after co++issioning of the network.These checks co+prise the e$aluation of statistical data collected in the Goperations and+aintenance centerG =MC> as well as +easure+ents b6 +eans of test +obile stationsto explore e.g. hando$er e$ents under realistic conditions unwanted hando$er +a6 leadto tra7c congestions in certain cells: or +a6 drain o tra7c fro+ other cells.

Detection of +ultipath propagation proble+s caused b6 big reAecting ob

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) Repetition

$obile Radio Network Planning Tasks

Collection of basic planning data

Terrain data ac"uisition

Coarse co$erage prediction

Network con&guration

(ite selection and &eld +easure+ents

Tool tuning

Network design

Data base engineering

Perfor+ance e$aluation and opti+i2ation

Collection of basic planning data

Custo+er +ust de&ne basic network perfor+ance goals ?

(i2e of ser$ice area and area t6pes

Tra7c load and distribution

Mobile classes and ser$ice "ualit6

*uture de$elop+ent =forecast>

!$ailable R* 5 bandwidth

The resulting no+inal cell plan is a &rst planning approach

to deter+ine the re"uired nu+ber of radio stations

to &gure out the approxi+ate e"uip+ent con&guration

to get an idea of the &nancial $olu+e of the pro

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Network con-guration

@nternal con&guration of indi$idual radio station ?

/"uip+ent to be installed

Con&guration of the radio network = network structure > ?

Nu+ber of base station controllers B(C

Nu+ber of location areas

De&nition of data lines between the network ele+ents

"ite selection and -eld measurements

(election of de&niti$e radio site locations

Radio +easure+ents in t6pical areas

Radio +easure+ents in co+plex topographical regions

Tool tuning

Radio +easure+ents are exploited to adapt standard propagation +odels to speci&cen$iron+ental conditions

Resulting +odels +a6 be applied in si+ilar en$iron+ent

or are restricted to the special +easure+ent area

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Network design

The &nal radio planning is perfor+ed b6 +eans of the area 5 adapted +odels

Planning goals?

(u7cient signal le$el throughout the planning region

(u7cient tra7c capacit6 according to subscriber distribution

!ssign+ent of radio carriers to all cells

4ow interference le$el for co5channels and ad

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+ Radio 5ave Propagation

There are three +ain co+ponents of radio propagation which are discussed in the next

section?

+ean path loss =loss due to the distance between M(5B(>:

shadowing =long ter+ fading>:

+ulti path propagation short ter+ =Ra6leigh> fading.

+'# Pat 6oss

(tandard path loss +odels are of the for+?

4+LdB ! O B log d Lk+

where 4+ is the +ean propagation path loss between the base station =B(> and the+obile station =M(> at a distance d.

!? unit loss at 1 k+:

B? propagation index or loss per decade.

The propagation coe7cients ! and B depend upon?

the trans+it fre"uenc6:

the M( and B( antenna heights:

the topograph6 and +orpholog6 of the propagation area.

/xa+ples are?

#' Free space loss!

40 #.% O 0 log f LMJ2 O 0 log d Lk+

or +ore i+portant propagation in real en$iron+ent 5 the fa+ous Jata +odel?

)' 7ata model

The Jata +odel describes the +ean propagation eects for large cells and distances d 1 I+. *or urban en$iron+ent one has?

! ).'' O ).1) log f 5 1#.- log Jb 5 a=J+>

B %%. 5 ).'' log Jb

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*re"uenc6? f LMh2 1'0...1000 5Mh2

B( antenna height? JbL+ #0...00 +

M( antenna height?J+L+ a=J+> 0 for J+ 1.' +

/xa+ple? J+ 1.' + Jb '0 + f00 Mh2

! 1#.# B ##.-

Pat 6oss for 6argeCells 8 7ata $odel 9:"$ 244;

B( height '0 +M( height 1.' +

90

100

110

120

130

140

150

10

1!0

1"0

190

200

210

220

1 10 100

Cell radius [km]

Path

Loss[d #r$an

#r$an %ndoor

&u$ur$an

'ural (quasi open)

'ural (open)

*ig.

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*or other en$iron+ents =suburban: rural5"uasi5open> the path loss per decade re+ainsthe sa+e: but the unit loss is reduced b6 a certain a+ount. The free space loss and theJata +odel are illustrated in the &gure abo$e.

Models of this t6pe are ade"uate for esti+ating the recei$ed le$el for large cells.Jowe$er for a real network planning: re&ne+ents of the +odel and adaptations ofpara+eters to +orphological and topographical data and to +easure+ent $alues arenecessar6 =refer to section 1>.

The s+aller the cells: the +ore i+portant are the details of e.g. the building structurewithin the cell.

+') "adowing 8 6ong Term Fading

@n larger cells where the B( antenna is installed abo$e the roof top le$el: details of theen$iron+ent near the M( are responsible for a $ariation of the recei$ed le$el around the+ean le$el calculated b6 the +odels discussed abo$e.

Qsuall6 this $ariation of le$el 5 caused b6 obstacles near the M( =e.g. buildings or trees> 5is described b6 the statistical +odel: i.e. the total path loss 4 totis gi$en b6 the +eanHdistanceG path loss plus a rando+ shadowing

4totLdB 4+ O (

(0? free line of sight:

(0? strong shadowing b6 e.g. a high building near the M(.

( has a Kaussian distribution =see &gure below> with +ean $alue 0 and a standardde$iation s which t6picall6 lies in the range s %...10 dB.

5# 5 #51 10

0.1

0.

0.#

0.'

0.%

(hadowing (s LdB

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*ig. # Kaussian distribution of (hadowing (

The length scale for $ariation of the long ter+ fading is in the range ' ... 100 +: i.e. thet6pical si2e of shadowing obstacles.

+'+ $ulti Pat Propagation 8 "ort Term Fading

The superposition of se$eral reAected wa$es arri$ing at the recei$er on dierent pathsand therefore with dierent a+plitudes and phases causes peaks =constructi$esuperposition> and deep fading dips = destructi$e superposition> of the recei$ed le$el.

The length scale for $ariation =e.g. peak to peak> is gi$en b6 the half of the trans+issionwa$e length: i.e. about 1' c+ for K(M00 or ,.' c+ for DC(1-00. !n exa+ple for the$ariation of the recei$ed le$el due to short ter+ fading is shown in the &gure below.

! co+parison with the length scale for shadowing explains the na+es for these fading

t6pes.

The statistics of the Ra6leigh fading is described in the following wa6?

Consider the recei$ed le$el due the path loss and long ter+ fading which is called local+ean? 44CLdB+. The recei$ed local +ean power is then gi$en b6

PlocL+3 104lC10

Qsing this for+ula the probabilit6 densit6 function for the recei$ed power P is gi$en b6?

f=P> 1PlocS exp=5PPloc>

which +eans that the probabilit6 function for the signal a+plitude P !is gi$en b6 aRa6leigh distribution.

Qsing these for+ulas and so+e +athe+atics: one can calculate the probabilit6 that therecei$ed le$el 4 =aected b6 Ra6leigh fading> is x dB below the local +ean le$el 4 loc?

Prob =4 5 4loc x dB> 1 5 exp = 5 10 x10>

3

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Coerence Bandwidt and (elay "pread

BTcoh

=1

i.e. the higher the dela6 spread the lower is the coherence bandwidth.

The dela6 spread depends upon the propagation en$iron+ent. T6pical $alues are?

10 Us for hill6 terrain =corresponding to path length between dierence of # k+>.

0.1 ... 1 Us for urban area =corresponding to path length between dierence of #0 ...#00 +>.

Ieeping in +ind that a Ra6leigh fading dip of +ore than 10 dB occurs with a probabilit6

of 10 : +easures should be pro$ided to co+bat Ra6leigh fading?

$eans to combat Rayleig fading!

!$eraging of Ra6leigh fading o$er speech fra+es =interlea$ing of - bursts>

5 Fre%uency 7oppingspacing between fre"uencies in hopping se"uence coherence bandwidth

5 $otion=speed $>/xa+ple? $'0 k+h: distance between bursts TDM! fra+e length T %.) +s

distance between M( positions at subse"uent bursts D ).% c+distance for - burstsV - S D '0 c+ # S wa$elength

Co+bining of signals recei$ed at positions of +utuall6 uncorrelated fading

5 *ntenna (iversityspacing between R8 antennas half wa$elength

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*ig. %

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"ort Term Fading

*ig. '

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+', $a at the trans+itter antenna and there"uired input power le$el =R@P4> at the recei$er antenna.

Output BT"!

/@RPBT( Power !+pli&er utput 5 Co+biner 4oss 5 Downlink Cable 4oss O !ntenna Kain

Power *mpli-er Output! ' 3att %% dB+ =K(M00>=higher power a+pli&er output power in further BT( $ersions>

Combiner 6oss

Co+biner T6pe 1?1 ?1 %?1

Duplexer ., dB ., dB '. dB

J6brid Co+biner .0 dB '. dB -.% dB

*ig. )

The ratio x?1 denotes the nu+ber of carriers which are co+bined. @n the case of h6bridco+biners the signals are fed to 1 trans+itter antenna. @n the case of duplexers thesignals are fed to antennas =on air co+bining> which are used for trans+ission as wellas for reception.

Qsing these antennas for reception: a two branch =+axi+u+ ratio> antenna di$ersit6co+bining can be reali2ed. This +eans that 5 using Duplexers 5 two antennas per cell areneeded: whereas when using J6brid Co+biners and appl6ing !ntenna Di$ersit6 tworecei$e plus one trans+it antenna is needed.

(ownlink *ntenna Cable 6oss!# dB =exa+ple>

*ntenna :ain =exa+ple>? 1) dB =t6pical $alue for )00half power bea+ width antenna>

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Output $"!

*or the M( there is no need co+bining dierent carriers and the cable loss and antenna

gain reduce to 2ero. The /@RP depends upon the power class of the M( speci&ed in K(MRec 0'.0'?

Power Class =K(M 0'.0'> Max. utput Power=K(M00>

Max. utput Power=DC(1-00>

1 55 1 3att #0 dB+

- 3att # dB+ 0.'3 % dB+

# ' 3att #, dB+ % 3att #) dB+

% 3att ## dB+

' 0.- 3att dB+

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*ig. ,

=nput BT"!

The re"uired input power le$el R@P4 at the BT( antenna is gi$en b6

R@P4BT( Recei$er (ensiti$it6 4e$el 5 !ntenna Di$ersit6 Kain O Qplink Cable 4oss 5 !ntenna

Kain

Recei$er (ensiti$it6 4e$el 5 10% dB+

The recei$er sensiti$it6 le$el is de&ned in K(M Rec. 0'.0' for scenarios where short ter+Ra6leigh fading is =at least> partl6 a$eraged either b6 +otion or b6 fre"uenc6 hopping.

The recei$er sensiti$it6 le$el has been +easured to be better than re"uired b6 K(M Rec.0'.0'.

*ntenna (iversity :ain! % dB =for a t6pical scenario>.

The gain which can be achie$ed b6 antenna di$ersit6 strongl6 depends upon thepropagation en$iron+ent: the $elocit6 of the +obile and on whether fre"uenc6 hoppingis applied or not.

*or a t6pical urban en$iron+ent: a +obile speed of # k+h and fre"uenc6 hoppingapplied the antenna di$ersit6 gain is about % dB.

>plink Cable 6oss # dB without tower +ounted prea+pli&er R8!MD

0 dB with tower +ounted prea+pli&er R8!MD

The =uplink> cable loss fro+ the antenna to the recei$er input can be co+pensated usinga tower +ounted a+pli&er called R8!MD.@t should be noted that this prea+pli&er cannot be used together with on air co+bining=Duplexers>.

*ntenna :ain =exa+ple>? 1) dB =t6pical $alue for )00half power bea+ width antenna>

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=nput $"!

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*or the M( there is neither antenna gain nor antenna di$ersit6 gain. Cable losses can beneglected. Therefore the re"uired input power le$el at the M( antenna is gi$en b6 theM( recei$er li+it sensiti$it6 as speci&ed b6 K(M 0'.0'?

10% dB+ for class and # =K(M00>: 10 dB+ for class % and ' =K(M00>: 100 dB+ for class 1 and =DC(1-00>

$a

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3: thefollowing $alues for link budget are obtained?

4uLdB 1'% dB4d LdB 1') dB

To obtain a s6++etric link budget: the power a+pli&er output power of the BT( has tobe reduced b6 dB. This is done using the ;M para+eter B(VT8P3RVR/D?

b in the ser$ing cellK(M? # dB+: 1' 1#dB+DC(? 0 #0 dB+: 1' 0dB+PC(? 0 #0 dB+: 1' 0dB+

#0 ## dB+: #1 #dB+

M(VT8P3RVM!8VCCJ M(T8PM!8CJ BT(5C 0...#1S dB

Maxi+u+ T8P3R a M( isallowed to use on the uplinkco++on control channel=Rando+ !ccess Channel:R!CJ> in the ser$ing cell?K(M? 0 %# dB+:1 'dB+DC(? 0 #0 dB+: 1' 0dB+

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*ig.

!nother eect illustrated b6 this exa+ple is the following?

(ince there is a balanced link budget 4uLdB 4dLdB: but a dierence of the recei$ersensiti$it6 le$el for the M( and BT( of dB: there is dierence between the +eandownlink and uplink recei$ed le$el R84/W of about dB?

R84/WVD4 5 R84/WVQ4 dB.

The conse"uence is that le$el threshold for e.g. the hando$er algorith+ ha$e to be set dB higher for the downlink than for the uplink.

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, Cellular Networks and Fre%uency *llocation

ne i+portant characteristic of cellular networks is the re5use of fre"uencies in dierentcells. B6 re5using fre"uencies: a high capacit6 can be achie$ed. Jowe$er: the re5usedistance has to be high enough: so that the interference caused b6 subscribers using thesa+e fre"uenc6 =or an ad.

taking the situation of the exa+ple abo$e and a path loss +odel 4 ! O B log d: onehas

C@totL3att C =@1O ... O @N@> C =N@S @1> N@? nu+ber of interferes

or in dB

C@totLdB CLdB 5 @totLdB B log D 5 B log R 5 10 log N@ B log DR 5 10 log N @ C@R+inO 4T*M =x>

B6 introducing the long ter+ fading +argin 4T*M =x> for a re"uired co$erage probabilit6of x: the eect of shadowing is taken into account.

*or ho+ogeneous hexagonal networks fre"uencies can be allocated to cells in as6++etric wa6. De&ning the cluster si2e I as group of cells in which each fre"uenc6 is

used exactl6 once: the following relations between Cluster (i2e: Cell Radius and Re5useDistance are obtained.

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@nserting the for+ula for the cluster si2e into the for+ula for the +ini+u+ C@R oneobtains?

0.' S B log # I C@R+in O 4T*M =x> O 10 log N@

which gi$es a lower bound for the cluster si2e which can be used.

*or a gi$en cluster si2e I and total nu+ber of fre"uencies Ntot: the nu+ber offre"uencies per cell Ncellis gi$en b6?

Ncell NtotI

i.e. the capacit6 of a cell can be increased b6 reducing the cluster si2e.

! reduction of cluster si2e can be achie$ed b6

reducing the nu+ber of interferers (ectorisation.

reducing the interference fro+ co5channel cells Power Control: DiscontinuedTrans+ission: ...

/xa+ples for sectori2ed network structure are shown in the &gures below. Methods forinterference reduction are discussed in chapter ).

b$iousl6 a real network does not ha$e such a regular hexagonal structure andfre"uenc6 allocation is perfor+ed b6 planning tools using co+plex algorith+s foropti+i2ing the C@R in each cell.

The ob

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+nicells 5 Cluster ,

5

3

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*ig. 1 /xa+ple for ho+ogeneous fre"uenc6 allocation

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#5(ector Clo$erleaf 5 Cluster # x #

1a

1$1c

2a

2$2c

3a

3$3c

1a

1$1c

2a

2$2c

3a

3$3c

1a

1$1c

2a

2$2c

3a

3$3c

1a

1$1c

2a

2$2c

3a

3$3c

1a

1$1c

2a

2$2c

3a

3$3c

1a

1$1c

2a

2$2c

3a

3$3c

1a

1$1c

2a

2$2c

3a

3$3c

*ig. 1# /xa+ple for ho+ogeneous fre"uenc6 allocation

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. Tra?c $odels

! tra7c +odel reAects the beha$ior of the subscribers: as their +obilit6: the +ean callrate or call duration. @t is needed e.g. for calculating the re"uired total nu+ber ofchannels within a cell and how to split the+ between tra7c and control channels.

These tra7c +odel infor+ation is alwa6s a +ixture between &eld obser$ations in si+iliarnetworks and arbitrar6 assu+ptions.

Tra7c data are $ariable in ti+e: therefore statistical characteri2ation is used.

The goal of planning is to +anage tra7c e$en in bus6 hour.

@n +obile networks we ha$e to e$aluate two +ain factors?

user +obilit6

co++unications

Qser +obilit6?

The user +o$es with a $elocit6 $.

*or exa+ple the hando$er and location update rates depend on this $elocit6.

Co++unications?

The nu+ber of subscriber in a cell: the tra7c per subscriber has to be considered.

*urther+ore: one needs infor+ation the +ean call duration: the +ean call cell rate =orbus6 hour call atte+pt BJC!>. separatel6 for +obile originating calls =MC> and +obileter+inating calls =MTC>.

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!n exa+ple for a tra7c +odel is gi$en in the table below?

nu+ber of call atte+pts =MCOMTC> per subscriber per hour 1:1

percentage of MC '-

percentage of XengagedY in the case of an MC 1:-

duration of TCJ occupation in the engaged case #s

no answer fro+ a person called b6 MC 1%:%

+ean TCJ occupation for this case #0 s

percentage of successful MC )':-

+ean ti+e for ringing =MC> 1' s

percentage of MTC %

no paging response #:'

duration of TCJ occupation in this case 0 s

no answer fro+ a +obile subscriber 1#:'

+eans TCJ occupation &r this case #0 s

successful MTC '%:0

+ean ti+e for ringing =MTC> ' s

+ean call duration =MCMTC> 11' s

+ean TCJ occupation call atte+pt -# s

TCJ load per subscriber 0:0' /rl

ti+e for MCMTC setup signaling on (DCCJ =authentications: ...> # s

ti+e for a location update ' s

nu+ber of location update per subscriber per hour :

resulting (DDCCJ load per subscriber =no TCJ "ueuing applied> 0:00% /rl

*ig. 1% (tandard tra7c +odel for K(M

The for+ula for calculating the load on the respecti$e dedicated channel are gi$en onthe next page.

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*ppendi< 3

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Jand6 sensiti$it6? 510 dB+

possible loss? 1'# dB+

1'# dB+ Z - k+ free area# k+ urban area1 k+ downtown

T6pical loss $alues?

*ading?Klass?3all?(hopping Mall?Jouse

) dB' dB

1 dB' dB1' dB

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