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Slide Title,Body TextSecond Level,EUROTEL STEERING GROUP,NOKIA TELECOMMUNICATIONS,NOKIAEXPLAIN.PPT/03.03.1998/MUh page:,*,we are HERE,Cellular Planning Principles,Scope of NW Planning,Network planning team,data acquisition,site survey and selection,field measurement evaluation,NW design and analysis,transmission planning,Network design,number and configuration of BS,antenna systems specifications,BSS topology,dimensioning of transmission lines,frequency plan,network evolution strategy,Network performance,grade of service(blocking),outage calculations,interference probabilities,quality observation,Customer requirements,subscriber forecasts,coverage requirements,quality of service,recommended sites,External information sources,terrain&morphological data,population data,bandwidth available,frequency co-ordination constraints,Interactions with,external subcontractors,site hunting teams,measurement teams,operator,switch planning engineers,Cellular Planning Principle,marketing,business,plan,traffic,assumptions,initial NW,dimensioning,freq.&inter-,ference plan,transmission,plan,final NW,topology,parameter,planning,coverage,plan,Key Dimensioning Quantities,Dimensioning quantities for radio network:,#of BS needed for coverage reasons,#of BS needed for traffic reasons,outage probabilities/percentages,interference probability vs.Frequency Re-use Rate,bandwidth used,Design goals are inter-dependant:,network can only be optimised with respect to one single aspect,Design goals to be applied must be clearly agreed with customer!,Coverage Planning,external inputs:,(traffic,subs.forecast,coverage requirements.),Initial NW dimensioning,TRXs,cells,sites,bandwidth needed,NW topology,nominal cellplan,suggestions for,site locations,cell parameters,coverage achieved,coverage prediction,signal strength,multipath propagation,coverage,ok?,site inspection,site accepted?,real cellplan,field measurements,planning,criteria fulfilled?,N,N,N,create cell,data for,BSC,go to,frequency,planning,Frequency Planning,Aim:find solution with minimum interferences in total NW,Traditional approach,hexagonal cell patterns,“regular grid,“cluster sizes,“frequency re-use distance D=R*sqrt(3*clustersize),R,D,Do not use this,ancient concept!,Macro Cell Network,Cost-effective solution,Good for covering large areas,large cell ranges,high antenna positions,Cell ranges 2.20km(depends on geography!),Good with low traffic volumes,typically rural areas,road coverage,Commonly used with omnidirectional antennas,use“split beams for road coverage,2.20 km,Optimise for coverage,Small Cell Network,Capacity oriented network,additional capacity by multiple cell coverage,Good for areas with high traffic,Mostly used with sectorised cells,most cost-efficient solution,best usage of available cell sites,Typical applications,medium towns,suburbs,Typical cell ranges:0,5.2km,0,5.2km,Optimise for capacity,Transmission Planning,Cost for transmission lines account for a great portion of NW operational costs per year=design for minimum overall costs!,Fixed part design,MSC,BSC,Hub,BTS,BSS,BTS,BTS,BTS,Radio part design,BTS,BSS,BTS,BTS,BTS,Network Topology,Prefer centralised or decentralised NW architecture?,2 small BSC plus,cheap transmission,1 large BSC plus,expensive,transmission,MSC,BTS,BSC,BTS,BTS,BTS,BSC/MSC,BTS,BTS,BTS,BTS,Microwave Links,High capacity transmission links,Operating frequencies:7.38 GHz band,Contra,needs extra frequencies,weather dependant link quality(rainfall),not always available at ideal sites(LOS path),long distance hops are problematic,Pro,low operating costs,easy to install,flexible,quick&reliable solution,Terminal,station A,Terminal,station B,Repeater,station,Leased Lines,Terrestrial lines rented from“3rd party operator,Contra,high operating costs,long lead times(installation),difficult to deploy(digging,groundworks.),often not available at ideal BTS sites,Pro,reliable transmission,no extra infrastructure to buy,long distances are uncritical,Analyse cost structure of Leased Line tariffs to decide whether LL or microwave links are more economical,Traffic Planning,Estimation of traffic expected,number of subscribers in area?,traffic load per subscriber?,geographical area to cover?=traffic per sq.km =traffic per cell=number of TRX needed per BS,allow extra capacity for roamers and busy hour traffic,“Bottle-neck of the system shall,not be in transmission lines,
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