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BTS Cell PlanningSection OneTraffic and Coverage
Planning
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Slide 2
Customer and Operator Requirements Cell Planning Process
Traffic and Coverage Analysis
Nominal Cell Planning (Macrocells)
Radio Link Budget Cell Plans, Splitting, Sectorisation
Number of Cells
Initial Cell Site Positioning
Predictions
Traffic Planning Frequency Planning
Outputs of Frequency Planning Process
Presentation OutlinePresentation Outline
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Slide 3
At the end of this course, attendees will: Have an appreciation of traffic forecasting,traffic dimensioning and cell planning principles
ObjectivesObjectives
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Slide 4
Guaranteed Access Coverage / Capacity
Choice of Services BW and Demand
Affordability Implementation and
Maintenance at Low Cost
Quality Cell Optimisation
Customer Network Operator
Customer and OperatorCustomer and Operator
RequirementsRequirements
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Slide 5
Traffic & Coverage
Analysis
Nominal
CellPlan
SurveysSystemDesign
Implementation
System
Optimisation
Cell Planning ProcessCell Planning Process
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Slide 6
Traffic and Coverage Analysis The purpose of this analysis is to prove there is aneed for coverage in an area and to estimate theamount of resources required to meet thecustomers requirements
Nominal Cell Plan (NCP) A nominal cell plan can be produced from the data
compiled in the traffic and coverage analysis. Thisplan provides the theoretical basis for furtherplanning. Normally the formulation of this planinvolves using measurement techniques and radioplanning tools.
Cell Planning ProcessCell Planning Process
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Slide 7
Surveys
Site surveys are carried out for all proposed site locationsand will include checks for space, facilities, etc.
Systems Design
Once the planning parameters have been adjusted to meetthe results of the surveys, the system can be fully designed.
This will involve the production of a final cell and equipmentplan to meet the coverage and capacity requirements
Implementation & Optimisation
After the system has been installed, it is continuouslymonitored to ensure that it meets the demand
Cell Planning ProcessCell Planning Process
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Slide 8
Analysis produces information aboutgeographical area and expected trafficdemand
Information includes:
Capacity Coverage
Grade-of-service
Available frequencies
Speech quality
System growth capability
Traffic Coverage and AnalysisTraffic Coverage and Analysis
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Slide 9
Geographical distribution of traffic demandcan be calculated from data such as:
Population distribution
Transport infrastructure and usage
Income level distribution Land usage data
Telephone usage statistics
Subscription and call charges and the price of
MSs Type of MSs subscribers use
Traffic and Coverage AnalysisTraffic and Coverage Analysis
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Slide 10
Portable
In-Car
In-Building
TrainSea
Oil Refinery
Areas and MobileTypes Coverage
Intended Depth ofIntended Depth of
PenetrationPenetration
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Slide 11
Intended Depth of Penetration
On-street at start-up
In-building coverage in subsequent roll-out years or fromday 1 e.g. Orange, UK. The radio engineer must knowwhen the operator intends to introduce in-buildingcoverage. The provision of superior quality communications in-building requires a
very dense network at start-up. In urban areas, sites can be as closeas 1.5 - 2 km
Usually operators rely on into-building coverage with the BTS deployedoutside and coverage being provided inside. This approach requiresthe availability of a good on-street propagation model for prediction
outside and penetration loss figures for different buildings e.g. glassfrontage buildings in business areas such as Sharq, buildings inresidential areas such as Qurain, Yarmouk, Khaldiya and Faiha.
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Slide 12
Intended Depth of Penetration Some buildings are considered to be very important andwill require the deployment of within-building transmitterse.g. microcell or picocell. Usually this deployment requiresa preliminary survey. For example, Holiday Inn inFarwaniya, MTC building in Shuwaikh.
The choice of in-building coverage will also determinewhich mobile classes are supported e.g. 0.8Whandportable or 2W mobiles.
Traffic and Coverage AnalysisTraffic and Coverage Analysis
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Slide 13
Train station platform, airports, sea ports and oil
refineries coverage in subsequent roll-out years. For underground train station platforms, the deployment of a
single base station is not enough. Usually special techniquessuch as leaky feeders are used.
Sea ports are usually covered with low base antenna sites to
prevent interference across the sea e.g. a site in Doha which ismounted at a high elevation, can still provide coverage to theArabian Gulf road in Sharq. Therefore it must be of a low height.
In oil refineries and petrochemical plants, there areconsiderable and sometimes severe restrictions on where basestations can be placed for very good reasons. Therefore sitepositioning in these areas must be done carefully.
Traffic and Coverage AnalysisTraffic and Coverage Analysis
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Slide 14
Traffic Coverage and AnalysisTraffic Coverage and Analysis
Coverage may be
provided in Sharq,Dasman and all areas
within the first ring roadfrom year 1
Coverage may beprovided in Farwaniya,
Khaldiya, Cordoba in year2
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Slide 15
Intended Geographical ExtentIntended Geographical Extent
Phase 1 may be the provision of coverage:
in the business areas e.g. Sharq, Dasman and other areas within theFirst Ring Road. Operators will usually begin with good coverage inbusiness and urban districts e.g. Orange UK in the M25 orbital.
in some important residential areas based upon the income levels ofthe inhabitants e.g. Yarmouk, Khaldiya, Faiha, Mishrif
Phase 2 may be the provision of coverage:
along important highways and in other dense residential areas where alarge proportion of subscribers will be expected to be e.g. Jabriya, andSalmiya, Salwa, on the outskirts of the main city e.g. Andalous,Firdous, Abu Halifa
in areas where there is an inadequacy of PSTN service and mobile
traffic will be expected to be higher e.g. Qurain
Phase 3 may be the provision of coverage: Along the desert roads, in the oil refineries, in sea ports
Traffic and Coverage AnalysisTraffic and Coverage Analysis
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Slide 16
Intended Market Penetration and Service ProvisionIntended Market Penetration and Service Provision
Based upon estimated population in different regions and throughmarket surveys, the determination of the number of subscribers tomake the operators business plans feasible.
Intended service at start-up and in subsequent roll-outs
All operators start out providing speech services only. In subsequent years (year 2onwards for example), operators introduce short message service and features of
GSM phase 1 such as call barring, forwarding. In subsequent years, operators will provide almost all GSM phase 1 and phase 2
service associated with speech e.g. calling line identification, call waiting, callhold. In subsequent years, support may be made available for bearer servicescontained in both GSM Phase 1 e.g. transmission of fax and computer data atbetween 2400 and 9600 bps
Traffic and Coverage AnalysisTraffic and Coverage Analysis
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Slide 17
Intended business and private traffic mixThis helps the radio engineer to quantify the volume of
traffic given the number of subscribers and estimatedusage for business and consumer users.
Intended Speech CODEC e.g. full-rate, enhancedfull rate or half-rate
the type of CODEC will also determine the number ofRCUs deployed.
Traffic and Coverage AnalysisTraffic and Coverage Analysis
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Slide 18
Measurement of Traffic
Traffic Coverage and AnalysisTraffic Coverage and Analysis
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Slide 19
timeoveralldurationaverageperiodaincallsof.n=flowTraffic
ErlangFlowTrafficofUnit =
hour1foruseconstantin(timeslot)channeltraffic1=Erlang1
025.03600
901scriberErlang/Sub
e.g.
=
=
subsperErlangssubs.ofno.ErlangsTotal =
Traffic Units - ErlangsTraffic Units - Erlangs
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Slide 20
1 subscriber subscriber does not use 1 Erlang. Instead
users have a % of an Erlang allocated to them whichdepends upon the average call length.
The formula for calculating the number of Erlangs for asubscriber is given as:
where A = traffic flow, C = number of calls in a period, td= average duration of one call and T = overall time.
In Kuwait, we usually set A = 0.060 Erlangs persubscriber. Assuming that we have C = 2 calls per hour,this means that the average call duration is 108seconds.
Traffic and Coverage AnalysisTraffic and Coverage Analysis
T
tC=A
d
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Slide 21
0
20
40
60
80
100
120
Traffic
1 3 5 7 9 11 13 15 17 19 21 23
Hours
The Busy HourThe Busy Hour
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Slide 22
The uninterrupted period of 60 minutes during which
the traffic is maximum is known as the busy hour and isgenerally used as the basis for traffic calculations.
The busy hour may vary on different days withvariations of three kinds:
Long-term growth or decline of traffic
Cyclical variations, weekly or seasonal Random variations due to unpredictable factors affecting general
level of demand in a cell on a particular day
Shorter peaks can occur in special circumstances e.g.natural disasters; system design however does not
normally account for all such eventualities In MTC Kuwait there are two significant busy hour
periods - 12pm-1pm and 6pm-7pm
The Busy HourThe Busy Hour
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Slide 23
Equipment ProvisionEquipment Provision
If just sufficient equipment were provided to carry theaverage traffic flow, an unacceptably high proportionof calls would encounter blocking.
Increasing the equipment beyond a certain limit would
not produce any significant improvement in service. The grade-of-service is the probability thatThe grade-of-service is the probability that
when a call request is made, all channelswhen a call request is made, all channels
are in use.are in use.
Typically operators use 2% grade-of-service
The Erlang B model is used
Grade of ServiceGrade of Service
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Slide 24
Model AssumptionsModel Assumptions
There are no reserved traffic channels
The number of users is greater than the number ofchannels
Call requests arrive randomly (Poisson distribution)
Blocked calls are lost (not held in a queue) Blocked calls abandon the attempt immediately I.e.
subscribers do not re-attempt the call when blocked.
The Erlang B model has been convertedThe Erlang B model has been converted
into a lookup table for ease of use.into a lookup table for ease of use.
Erlang B ModelErlang B Model
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Slide 25
Extract from Erlang B TableExtract from Erlang B Table
Determine
number oftimeslots
Select theGrade-of-Service
Determine
OfferedTraffic(2.8767Erlangs)
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Slide 26
If Offered traffic = A
Blocked traffic = A x Grade of ServiceCarried Traffic = A x (1 Grade of Service)e.g.7 Channels with a Grade of Service = 2% (fromErlang B Tables)
A = 2.9354
Therefore
Blocked Traffic = 2.9354 x 0.02 = 0.0587 Erlangs
Carried Traffic = 2.9354 x (1 0.02) = 2.8767Erlangs
Offered and Carried TrafficOffered and Carried Traffic
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Slide 28
Cell 1: Area = 2km2
Subscribers = 1000
A = 0.025 Erlangs / subscriber
Total Erlangs required = No subscribers x Erlangs per subscriber
= 1000 x 0.025= 25 Erlangs
From Erlang B table @ 2% Blocking 34 TFC+ 2 Timeslots for Control (BCCH, CCCH, SDCCH)
Therefore 36 timeslots total
= 5 Transceivers
Cell 2: Area = 2km2
Subscribers = 500
Total Erlangs required = 500 x 0.025 = 12.5 ErlangsFrom Erlang B table @ 2% Blocking 20 TFC
+2 Timeslots for Control (BCCH, CCCH, SDCCH)Therefore 22 timeslots total
= 3 Transceivers
Cell Resource RequirementsCell Resource Requirements
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Slide 29
x Cells: Area = 4km2 Subscribers = 150
A = 0.025 Erlangs / Subscriber
tal Erlangs required = No. of Subscribers x Erlangs per subscri= 1500 x 0.025= 37.5 Erlangs
From Erlang B table @ 2% Blocking 48 TFC
EACH CELL SUPPORTS24 Traffic Channels
+ 2 Timeslots for Control (BCCH, CCCH, SDCCH)26 timeslot total
= 4 Transceivers / Cell
Cell Resource RequirementsCell Resource Requirements
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Slide 30
Cell Resource Requirements - FrequencyCell Resource Requirements - Frequency
DrivenDrivenArea = 4 km2 Subscribers =
1500
No ARFCNs per cell = 2A = 0.025 Erlangs / subscriber
Total Erlangs required = No subscribers x Erlangs per subscriber= 1500 x 0.025= 37.5 Erlangs
From Erlang B table @ 2% Blocking 48 TFC
Traffic Channels / cell = (16 2 Control Timeslots)= 14 TFC
No of Cells = Total No TFCNo of TFC/Cell
= 4814
= 3.43 Cells
Total = 4 Cells, 8 Transceivers
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Slide 31
Traffic ForecastingTraffic Forecasting
The determination of traffic forecastsThe determination of traffic forecasts
for a GSM/ETACS network is undertakenfor a GSM/ETACS network is undertaken
using two approaches:using two approaches:
Market Research At Startup At network startup, traffic estimates in terms of number of
subscribers is obtained by conducting a market survey. Samples are taken of the number of people who would make
use of mobile telephone services given pricing levels for themobile phone, line rental and call charges. Initial penetrationfigures in most countries are usually between 5% and 10%.
Based upon penetration and total population figures, thetotal subscriber demand which must be supported by anetwork is determined. In Kuwait, with an estimatedpopulation of 2 million and 5% penetration, an initial startupdemand will be 100,000 subscribers.
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Slide 32
Business Area 30Industrial 5 %
Tourist
Residential 50 %
Traffic ForecastingTraffic ForecastingGiven the totalsubscriber figure,an Erlang densitymap can becreated basedupon clutter
weighting
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Slide 33
Traffic ForecastingTraffic Forecasting
Traffic Measurements From the Mobile SwitchingTraffic Measurements From the Mobile Switching
CentreCentre For advanced operators such as MTC, traffic measurements in
terms of number of Erlangs per cell are available from the MSCon an hourly basis.
The number of milliErlangs per customer can be estimated by
considering the percentage of successful calls as recorded bythe MSC and the maximum number of Erlangs recorded duringthe busy hour.
Traffic estimates are therefore made by considering:
Current average number of Erlangs per site
Measured annual growth rates
Projected number of milliErlangs per subscriber
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Slide 34
Traffic ForecastingTraffic Forecasting
In MTCs present position, trafficIn MTCs present position, traffic
forecasting will be based upon trafficforecasting will be based upon trafficmeasurements.measurements.
Traffic forecasting is concluded byTraffic forecasting is concluded by
assigning proportions of the total numberassigning proportions of the total number
of subscribers to the major roads such asof subscribers to the major roads such asthe First-Seventh Ring Roads and thethe First-Seventh Ring Roads and the
different regions.different regions.
Given a traffic demand figure of 200KGiven a traffic demand figure of 200K
subscribers, district traffic demand maysubscribers, district traffic demand maybe estimated as shown in the table on thebe estimated as shown in the table on the
next page.next page.
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Slide 35
Traffic ForecastingTraffic Forecasting
Reg io n C urre n tAverage
Er langs
Current Shareof T otal T raffic
New E st im atesof Erlan gs for
2 0 0 K s u b s .
C entral K uwait 1500 19.58% 2349.6
Yarm ouk 100 1.31% 157.
Qortoba 100 1.31% 157.2Qura in 1000 13.05% 1566
A hmadi 60 0 .78% 93.6
Jahra 200 2.61% 313.2
A z Zawr 800 10.44% 1252.8
S alm iya 800 10.44% 1252.8
Hawali 800 10.44% 1252.8
Jabriya 100 1.31% 157.2Fourth Ring Rd. 1500 19.58% 2349.6
F ifth Ring Rd. 1500 19.58% 2349.6
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Traffic ForecastingTraffic Forecasting
The objective of traffic planning is to determine the
number of DRCUs required for each cell for a givenspectrum allocation, grade-of-service and traffic demand.
From every BTS in the network, the maximum number oferlangs can be measured on a weekly basis. It should benoted that the maximum should be selected and not theaverage over the week since in resort area such as Al-
Zawr, there is virtually no traffic throughout the week withtraffic peaks over the weekend.
To establish traffic growth rates, regression line analysisshould be done fitting the number of measured erlangs tothe number of weeks.
Utilising the projected figures, realistic estimates can thenbe made of traffic demand for 3 months, 6 months andindeed 1 year in advance.
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Slide 38
Control ChannelsControl Channels
Each cell must support BCCH, CCCH and SDCCH inEach cell must support BCCH, CCCH and SDCCH in
order that signalling and synchronisation dataorder that signalling and synchronisation datacan be transferred between the BTS and the MSscan be transferred between the BTS and the MSs
One complete control message takes fourOne complete control message takes four
consecutive burstsconsecutive bursts
Combined into 1 multiframe
Non-combined in which case 2 separate multiframes exist ondifferent timeslots
BCCH in GSM is always on timeslot 0 of oneBCCH in GSM is always on timeslot 0 of one
transceivertransceiver
Configuration of other control channels (CCCHConfiguration of other control channels (CCCHand SDCCH) is up to the system vendorand SDCCH) is up to the system vendor
Control ChannelControl Channel
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Slide 39
COMBINED CONTROL MULTI-FRAME
TIMESLOT 01 BCCH message3 CCCH messages4 DCCH messages
NON-COMBINED CONTROL MULTI-FRAMES
TIMESLOT 01 BCCH message + 9 CCCH messages
ANY REMAINING TIMESLOT (e.g. T/S 1)8 DCCH messages
Control ChannelControl Channel
ConfigurationsConfigurations
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Slide 40
Calculating CCCH RequirementsCalculating CCCH Requirements
Total Required CCCH = PCH + AGCH
One CCCH block is transmitted every 51 frame multiframe, of duration 235.65 ms.
The message capacity of each CCCH block is therefore 4.25 messages per second.
PAGING BLOCKSPaging channel capability must be the same for all cells within a location area.
TYPE 1 Page 2 MSs using either IMSI or TMSI
TYPE 2 Page 3 MSs : 1 MS using either IMSI or TMSI
2 MSs using TMSI
TYPE 3 Page a maximum of 4 MSs using TMSI
Paging Capability = (No. of MS paged per message
No. of Messages per second)
e.g. Using TYPE 3 paging request messages
Paging rate = 4 4.25= 17 MS pages/sec
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Slide 41
Mobile Paging RateMobile Paging Rate
e.g.
Subscribers in a Loc. Area = 30,000
Traffic Flow = 0.025 Erlangs / Subscriber
Average Call Duration = 90 seconds
No. of pages per call = 2
% Calls MS Terminated = 25%Type of paging message = TMSI
Total Loc. Area Traffic = 30,000 0.025
= 750 Erlangs
Loc. Area Call Rate = 750 / 90
=8.333 calls per second
Mobile Paging Rate = 8.33 2 0.25
= 4.2 MS pages / second
No. of CCCH blocks = 4.2 / 17 = 0.25
Mobile Paging Rate = Location Call Rate Number of Pages Per Call % MS Terminated calls
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Slide 42
e.g.
Cells Traffic capacity = 37.5 Erlangs
Traffic Flow = 0.025 Erlangs / Subscriber
Ratio Loc. Updates Calls = 2.2
Ratio SMS Calls = 0.2
Ratio Supp. Service Calls = 0.3
Ratio IMSI detach Calls = 0.2
Cell Call Rate = 37.5 / 0.025
= 1,500 Calls / Busy Hour
Loc. Updates = 1,500 2.2 = 3,300
SMS messages = 1,500 0.2 = 300
Supp. Services = 1,500 0.3 = 450
IMSI Detaches = 1,500 0.2 = 300
TOTAL = 4,350
Total Access Grant = 1,500 + 4,350
Events in Busy Hour = 5,850 / Hour 1.63/secNo. of CCCH blocks = 1.63 / 8.5 0.19
No. of CCCH Blocks = Total Access Grant Events
One CCCH Block access granting capability
Access GrantingAccess Granting
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Slide 43
SDCCHSDCCH
COMBINED CONTROL MULTI-FRAME
1 BCCH + 3 CCCH messages
4 SDCCH messages
NON-COMBINED CONTROL MULTI-FRAMES
1 BCCH message + 9 CCCH messagesAny Timeslot(s): 8 SDCCH messages
Call set-up probability of SDCCH blocking will be less than that for traffic channelsLocation updating automatic & periodically
IMSI attach/detach SMS point to point messages Supplementary Services
COMBINATIONS OF CONTROL MULTI-FRAMES
COMBINED CONTROL MULTI-FRAME
SDCCH NON-COMBINED CONTROL MULTI-FRAME
(T/S 0)
(T/S 1)
SMS CELL BROADCASTCBCH replaces 1 SDCCH message
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Slide 44
Calculating SDCCH Traffic FlowCalculating SDCCH Traffic Flow
Traffic Flow = No. of Calls DurationTime
e.g.Cells Traffic capacity = 37.5 Erlangs
Traffic flow = 0.025 Erlangs/Subscriber
Ratio Loc. Updates Calls = 2.2
Ratio SMS Calls = 0.2
Duration of Call Set-up = 3 seconds
Duration of Loc. Set-up = 4 seconds
Duration ofSMS = 6 seconds
Cell Call Rate = 37.5 / 0.25 = 1,500 Calls/Busy Hour
SDCCH Traffic Flow = (No. of SDCCH Calls Duration)Time
Loc. Updates = 1,500 2.2 = 3,300
SMS messages = 1,500 0.2 = 300
Call Set-up = 1,500 3 = 4,500
Loc. Updates = 3,300 4 = 13,200
SMS messages = 300 6 = 1,800TOTAL = 19,500
Erlangs = 19,500 / 3600 = 5.4167
No. of SDCCH Channels @ 1% = 12
ontro anne son ro anne s
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Slide 45
ontro anne son ro anne sDimensioningDimensioning
The control channel (BCCH, CCCH andThe control channel (BCCH, CCCH and
SDCCH) dimensioning is usually doneSDCCH) dimensioning is usually done
entirely by the systems vendorentirely by the systems vendor
(Motorola or Nokia)(Motorola or Nokia)
MTC however can dimension trafficMTC however can dimension traffic For GSM systems, the channel to carriermapping used by Motorola gives an indication ofthe number of carriers to be deployed in thecell.Number of Carriers Number of available Traffic TCH Timeslots or channels
1 6 (1 BCCH + 1 SDCCH)
2 14 (1 BCCH + 1 SDCCH)
3 22 (1 BCCH + 1 SDCCH)
4 29 (1 BCCH + 2 SDCCH)
5 37 (1 BCCH + 2 SDCCH)
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Slide 46
Traffic And Coverage AnalysisTraffic And Coverage Analysis
Coverage CriteriaCoverage Criteria
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Slide 47
Coverage ReliabilityCoverage Reliability
Coverage reliability must be specified for:Coverage reliability must be specified for:
on-street in urban, dense-urban, rural and businessdistricts e.g. 95%
in-car in urban, dense-urban, rural and business districts
e.g. 94% in-building in urban, dense-urban, sub-urban and
business e.g. 90%
Link budget calculations for both uplink andLink budget calculations for both uplink and
downlink enable the determination of thedownlink enable the determination of therequired signal levels at the mobile torequired signal levels at the mobile to
guarantee the selected coverage criteriaguarantee the selected coverage criteria
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Slide 48
Cell Planning ProcessCell Planning Process
Nominal Cell PlanNominal Cell Plan
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Slide 49
Nominal Cell PlanningNominal Cell Planning
The nominal cell planning process involves the creation of aThe nominal cell planning process involves the creation of a
plan of base station structures/cells modelled on a cellular grid.plan of base station structures/cells modelled on a cellular grid. Key factors in designing an NCP are:Key factors in designing an NCP are:
Location of cell sites
Antenna parameters
Base station output power
Propagation models
Cellular grids adopted Channel distribution and group allocation
Coverage CriteriaCoverage Criteria
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Slide 50
Input InformationInput Information
Defined service areas and roll-out plans e.g. intending to cover First Ring Road, Second Ring Road,
Fahaheel Expressway
e.g. provision of in-building coverage
Handportable and mobile role Projection of number of customers and
approximate geographical location
System usage per customer in the busy hour
obtaining the number of milliErlangs per subscriber Acceptable grade of service (blocking)
e.g. 2% excluding blocking on the PSTN
NCP InputsNCP Inputs
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NCP N k Pl i T l
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Slide 52
NCP - Network Planning ToolsNCP - Network Planning Tools
i h d lNCP D i M th d l
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Slide 53
Determine radio link budgetDetermine radio link budget
Calculate the maximum pathloss for different mobile units
Calculate required level of service.
Use radio propagation models to determineUse radio propagation models to determine
the maximum cell radius for different terrainthe maximum cell radius for different terrain
environments within the service area fromenvironments within the service area fromcoverage point-of-view.coverage point-of-view.
Evaluate traffic projections to determine theEvaluate traffic projections to determine the
optimum number of cells to support theoptimum number of cells to support the
number of subscribers.number of subscribers.
Based upon the figure obtained from coverageBased upon the figure obtained from coverageand traffic determine cell radius for bothand traffic determine cell radius for both
coverage and capacity.coverage and capacity.
NCP Design MethodologyNCP Design Methodology
NCP D i M h d lNCP D i M th d l
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Slide 54
Establish initial radio site locations and aEstablish initial radio site locations and a
cellular grid.cellular grid. Perform network wide propagation predictionsPerform network wide propagation predictions
and statistical coverage analysis.and statistical coverage analysis.
Re-evaluate traffic performance and considerRe-evaluate traffic performance and consider
the suitability of the initial cellular structure.the suitability of the initial cellular structure. Evaluate growth plans and cell splitEvaluate growth plans and cell split
requirements for each siterequirements for each site
Define cell reuse strategy and undertake initialDefine cell reuse strategy and undertake initial
frequency planningfrequency planning
Optimise frequency planOptimise frequency plan
NCP Design MethodologyNCP Design Methodology
R di Li k B dR di Li k B d t
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Slide 55
Radio Link BudgetRadio Link Budget
Parameter Example ValueStandard deviation of received signal on-street 7 dBStandard deviation of received signal in-building 7dB, overall std. 9.9 dBStandard deviation of received signal in-car 3 dB, overall std 7.6 dB
Urban in-building penetration loss 15 dBSub-urban and rural in-building penetration loss 10 dB
In car penetration loss 5 dBTri-sector base station antenna
Type 60 degree sector
Gain 18 dBiBeamwidth 65 H/ 6.5VMobile station antennaType OmniGain -2dBi
Transmitter Feeder Loss - 2dB
Transmitter Combiner Loss 2.5 dBReceiver Sensitivity -102 dBm (mobile end)
-107 dBm (base end)
Body Loss 3 dBDiversity Gain 3 dB
Mobile Output Power 0.8 WNominal Transmitter Power 44 dBm (25 W)
R di Li k B d tR di Li k B d t
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Slide 56
Radio Link BudgetRadio Link BudgetOn-street Coverage @ 95 %
Area probability
In-car coverage @ 94 % Area
probability
Urban In-building Coverage
@ 90% Area Probability
Downlink Uplink Downlink Uplink Downlink Uplink
TransmitterTX Peak Power (A) 43 dBm 29 dBm 43dBm 29 dBm 43 dBm 29 dBm
Combiner Loss (B) -4.5 dB 0 dB -4.5 dB 0 dB -4.5 dB 0
Feeder Loss (C) -2.5 dB 0 dB -2.5 dB 0 dB -2.5 dB 0
TX Antenna Gain (D) 18 dBi -2 dBi 18 dBi -2 dB 18 dBi -2dBi
Body Loss (E) 0 dB 3 dB 0 dB 3 dB 0 dB 3 dB
TX EIRP (F) 54 dBm 24 dBm 54 dBm 24 dBm 54 dBm 24 dBm
Receiver
Receiver Sensitivity (G) -102 dBm -107 dBm -102 dBm -107 dBm -102 dBm -107 dBmDiversity Gain (H) 0 dB 4 dB 0 dB 4 dB 0 dB 4 dB
RX Antenna Gain (J) -2dBi 18 dBi -2 dBi 18 dBi -2dBi 18 dBi
Body Loss (K) 3 dB 0 dB 3 dB 0 dB 3 dB 0 dB
Feeder Loss (L) 0 dB 2.5 dB 0 dB 2.5 dB 0 dB 2.5 dB
Penetration Loss 0 dB 0 dB 5 dB 5 dB 15 dB 15 dB
Overall std Deviation 7 dB 7 dB 7.6 dB 7.6 dB 9.9 dB 9.9 dB
Fading Margin,
n=3.314 (M)
7.4 dB 7.4 dB 7.5 dB 7.5 dB 7.8 dB 7.8 dB
Isotropic Required RXSignal Level (N)
-89.6 dBm -119.1 dBm -84.5 dBm -114 dBm -74.2 dBm -103.7 dBm
Maximum Pathloss (P) 143.6 dB 143.1 dB 138.5 dB 138 dB 128.2 dB 127.7 dB
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Slide 57
ggCalculationsCalculations
Procedure:Procedure:
Calculate the EiRP for the uplink F = A + B + C + D
Calculate the expected isotropic received signallevel for uplink:
N = G - H - J + K + L + N + M
Calculate the maximum pathloss as perceived inthe uplink
P = F - N
Calculate the expected isotropic received signallevel for the downlink N = G - H - J + K + L + N + M
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Slide 58
ggCalculationsCalculations
Procedure:Procedure:
Calculate the required downlink EIRP F = P+N
Calculate the required downlink transmitterpower
A = F - B - C - D
Select the most appropriate transmitter level assupplied by the manufacturer
Reproduce link budget table using the readily
available transmitter and BTS antenna.
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Slide 59
ggCalculationsCalculations
Note:Note:
Overall in-building and in-car standard deviation are calculated as:
in-building
in-car
overall on street in building
=
+
2 2
overall on street in building
=
+
2 2
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Slide 60
Cell Link BalancingCell Link Balancing
Both up- and downlinks must be balanced to exclude the
possibility of having regions where the base is able toprovide coverage, but the mobile cannot transmitsufficient power in the uplink or detect sufficient signal inthe downlink. An example is when a subscriber connectedto the PSTN cannot clearly hear what the mobile user issaying but the mobile user can hear what is being said on
the PSTN.
Since the uplink is usually the limiting link, cell balancingusually requires the adjustment of BTS transmit power orthe selection of different antenna type.
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Slide 61
Cell Link BalancingCell Link Balancing
Signal enhancing techniques such as antenna
diversity, increased receiver sensitivity andmasthead amplifiers are also used at the basestation to improve the uplink.
Co- and Adjacent ChannelCo- and Adjacent Channel
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Slide 62
To achieve high network capacity and high
quality interference free service, a relativelyhigh carrier-to-interference ratio is required.
Theoretical predictions indicate that a C/Imargin of 9 dB is suitable for acceptable speech
quality. In a practical network, operators should design
systems for no less than 15 dB over 90% oflocations !
jj
InterferenceInterference
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Slide 64
C/I Cumulative DistributionC/I Cumulative Distribution
A
C C
A 80% of calls must have a C/I better
than C/I80 where C/I80 =9 dB
0.8
0.9
1
0.3
0.4
0.5
0.6
0.7
0.2
0.1
0
50403020100-10
Pr
ob
abi
lity
C/I (dB)
C
A
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Slide 65
p gp gSectorisationSectorisation
Reuse PatternsReuse Patterns
In cellular, frequencies are reused to maximise traffic handlingcapability of a network with limited frequency allocation.
Cell plans can be based upon
7/7 i.e. seven cell repeat with omni-directional base stations
7/21 i.e. seven cell repeat with each site divided into three sectors served by threedirectional antennas
4/4 i.e. four site repeat with omni-directional base stations
4/12 i.e. four site repeat with tri-sector cell base stations (also called 4/3)
3/3 i.e. three site repeat with omni-directional base stations
3/9 i.e. three site repeat with tri-sector cell base stations (also called 3/3)
The appropriate cell reuse pattern must be selected to match thetraffic and co-channel interference requirements.
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Slide 66
p gp gSectorisationSectorisation
Omni cell siteOmni cell site
Tri-sector cell siteTri-sector cell site
Cell Site
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Slide 67
p gp gSectorisationSectorisation
1
45
36
7 2
7 Site Repeat, Omni-cells (Also called7 Site Repeat, Omni-cells (Also called
7/7)7/7)
1
4536
7 2
1
45
36
7 2
5
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12 Cell Reuse Pattern12 Cell Reuse Pattern
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Slide 69
C G
B
H
I
D
K
LJ
E
F
A
5
19
7
G
20
8
H
21
9
I
22
10
J
23
11
K
24
12
L
15
3
C
16
4
D
17
5
E
18
6
F
1413
21
Channels
BAGroup
Channels Available
1 -24
12 Cell Reuse Pattern12 Cell Reuse Pattern
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Slide 70
SectorisationSectorisation
Traditional analog systems such asTraditional analog systems such as
ETACS and TACS employ the 7/21ETACS and TACS employ the 7/21reuse pattern for control channels andreuse pattern for control channels and
the 4/12 reuse pattern for voicethe 4/12 reuse pattern for voice
channels.channels.
GSM systems employ 3/9 and 4/12GSM systems employ 3/9 and 4/12
depending upon the spectrumdepending upon the spectrum
allocation.allocation.
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Slide 71
SectorisationSectorisation
With a 7/21 reuse pattern, the total spectrum allocation
must be divided into 21 groups With a 4/12 reuse pattern, the total spectrum allocation
must be divided into 12 groups
With a 3/9 reuse pattern, the total spectrum allocationmust be divided into 9 groups
The smaller the reuse pattern the higher theThe smaller the reuse pattern the higher thecapacity the system can support e.g. 3/9 cancapacity the system can support e.g. 3/9 can
support a higher capacity than the 7/21.support a higher capacity than the 7/21.
However, the lower the available co-channelHowever, the lower the available co-channel
interference margin e.g. 7/21 provides a C/I ininterference margin e.g. 7/21 provides a C/I in
excess of 20 dB for 90% of locations comparedexcess of 20 dB for 90% of locations comparedto 10-11 dB for 90% of locations for 3/9.to 10-11 dB for 90% of locations for 3/9.
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Slide 72
SectorisationSectorisation
Cell are split i.e. reduced in coverage area,Cell are split i.e. reduced in coverage area,
to increase the traffic handling capabilityto increase the traffic handling capabilityof the systemof the system
Usually smaller cells of radius between 1.5Usually smaller cells of radius between 1.5
km and 2km are deployed in urban areaskm and 2km are deployed in urban areas
where traffic demand is higherwhere traffic demand is higher In sub-urban areas, cell sizes typicallyIn sub-urban areas, cell sizes typically
range between 3km and 7km.range between 3km and 7km.
In rural and desert areas, cell sizes rangeIn rural and desert areas, cell sizes range
between 7km and 10-12 km.between 7km and 10-12 km. GSM has a maximum limit of 35 km radiusGSM has a maximum limit of 35 km radius
on cell size.on cell size.
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Slide 73
SectorisationSectorisation
Cell splitting can be carried out usingCell splitting can be carried out using
any one of two methods:any one of two methods: Face splitting: In face splitting, the original cell
area is divided into four equal parts, and the newcell radius after splitting is half the original size.
Corner splitting: In corner splitting, the originalcell area is divided into three equal parts and thenew cell radius after splitting is sqrt(3) x originalcell radius.
The corner splitting method is mostThe corner splitting method is mostcommonly used since it results incommonly used since it results in
fewer cells overall.fewer cells overall.
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Slide 74
SectorisationSectorisation
Corner Splitting Face Splitting
The new hexagon has
an area 1/3rd of theoriginal hexagon size
The new hexagon has
an area 1/4th of theoriginal hexagon size
cornerface
C i C ll / IUOC t i C ll / IUO
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Slide 75
Concentric Cells / IUOConcentric Cells / IUO
1 Call Set-Up2 Traffic
Under-Laid
Mini Cell
Over-Laid
Macro Cell
BCCH Carrier
Tighter Frequency ReuseTighter Frequency Reuse
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Slide 76
A2A3
A1
D2D3
D1
C2C3
C1
B2B1
B3
7
C2
8
D2
9
A3
10
B3
11
C3
12
D3
3
C1
4
D1
5
A2
6
B2
21Channels
B1A1Group
Macro Layer 4 Site 3 Cell Re-Use
A2A3
A1
D2D3
D1
C2C3
C1
B2B1
B3
9
A3
10
B3
5
A2
6
B2
21Channels
B1A1Group
Underlay Layer 2 Site 3 Sector Re-Use
Tighter Frequency ReuseTighter Frequency Reuse
Number of CellsNumber of Cells
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Slide 77
Number of CellsNumber of Cells
The number of cells to deploy to cover theThe number of cells to deploy to cover the
service area is governed by two factors:service area is governed by two factors: Size of the coverage area
Traffic Demand
The number of cells required to support theThe number of cells required to support the
expected traffic demand may exceed theexpected traffic demand may exceed thenumber of cells required for coverage andnumber of cells required for coverage and
vice versa.vice versa.
The systems designer must thereforeThe systems designer must therefore
calculate the expected number utilising bothcalculate the expected number utilising both
approaches and then select the higher value.approaches and then select the higher value.
Number of Cells (Example)Number of Cells (Example)
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Slide 78
Number of Cells (Example)Number of Cells (Example)
Given the following input parameters:Given the following input parameters:
Frequency spectrum of 15 MHz i.e. 75 GSM carriers
4/12 frequency reuse pattern and therefore 12 carriergroups
A system loading of 66-75% at roll-out
A grade-of-service of 2% blocking Erlang B traffic model
An Erlang per subscriber figure of 0.06
A uniformly distributed subscriber base of 100,000
and the GSM carriers to traffic channel mappingshown in the table
Number of Cells (Example)Number of Cells (Example)
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Slide 79
Number of Cells (Example)Number of Cells (Example)
N u m b e r o f C a r r ie r s
o r D R C U s
N u m b e r o f G S M F u l l -
R a te T r a f fic C h a n n e l s
O ffe r e d E r la n g s
a t 2 % b l o c k i n g
O f fe r e d f u ll -r a t e
s u b s c r i b e r s
1 6 2 .2 8 3 8
2 1 4 8 .2 0 3 7
3 2 1 1 4 .0 4 2 3 44 2 9 2 1 .0 4 3 5 1
5 3 6 2 7 .3 4 4 5 6
6 4 3 3 3 .7 6 5 6 3
7 5 1 4 1 .1 9 6 8 6
8 5 8 4 7 .7 6 7 9 6
Number of CellsNumber of Cells
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Slide 80
Number of CellsNumber of Cells
then the required number of cells tothen the required number of cells to
satisfy traffic can be calculated assatisfy traffic can be calculated asfollows:follows:
With 75 carriers available, between 6 and 7carriers can be used in each cell in a 4/12 reuse
pattern. Assuming a maximum of 6 with 66% loading, a
total of 4 carriers (or DRCUs) can be used.
From the carrier to channel mapping table, 4
carriers will give 29 traffic channels. 29 traffic channels will support a total of 21.04
Erlangs at a blocking probability of 2%.
Number of CellsNumber of Cells
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Slide 81
Number of CellsNumber of Cells
Therefore, assuming an Erlang per subscriber
figure of 0.06, the number of subscribers whichcan be supported in each cell on average is 351.
With a uniformly distributed traffic load of100,000 subscribers, the network will require
100,000/351 = 285 cells or 95 sites. Thus the total number of sitesThus the total number of sites
required for traffic purposes is 95.required for traffic purposes is 95.
Number of CellsNumber of Cells
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Slide 82
Number of CellsNumber of Cells
The number of cells required from aThe number of cells required from a
coverage area point of view can becoverage area point of view can bedetermined as follows:determined as follows:
Having calculated the minimum acceptablesignal level (e.g. -88 dBm) and the required BTS
transmit power to provide communications fromthe link budget, the expected cell area can bedetermined in different environments.
For example, Sharq which is a business district
area will require a cell size smaller than Ahmadior Manqaf which are low residential areas.
Number of CellsNumber of Cells
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Slide 83
Number of CellsNumber of Cells
The cell area is determined using a planning
tool such as ARTEMIS or PlaNET by arbitrarilypositioning up to five sites in the intendedservice area, calculating the average coveragearea from a site at the threshold of -88 dBm.
The traditional method of calculating cell sizes
for individual clutter types using thepropagation model is not valid since clutter isnot necessarily homogeneous throughout cellarea and because mapping data used today
may consist of up to 25 categories some ofwhich will have very small coverage.
Number of CellsNumber of Cells
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Slide 84
Number of CellsNumber of Cells
Assuming tri-sectors, the theoretical area from a site
is given as:
thus the number of sites required = total area forservice / site area.
The figure obtained from this analysis should becompared with the result obtained for traffic demand.
The higher of the two values should be selected.
The expected cell radius can be determined from thesite area which is determined as:
site area = total service area / number of sites
3 3
8
2R
Initial Cell Site PositioningInitial Cell Site Positioning
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Slide 85
Initial Cell Site PositioningInitial Cell Site Positioning
Cellular radio networks are often shownCellular radio networks are often shown
as a regular pattern of hexagons withas a regular pattern of hexagons withsites nicely ordered along hexagonalsites nicely ordered along hexagonal
clutter patterns. This is very seldom theclutter patterns. This is very seldom the
case in reality where reluctant landlordscase in reality where reluctant landlords
or indeed the terrain limit the choice ofor indeed the terrain limit the choice ofsite positions. Also sites will usually besite positions. Also sites will usually be
placed in important areas for coverageplaced in important areas for coverage
reasons and where a lot of traffic isreasons and where a lot of traffic is
expected such as main road junctions,expected such as main road junctions,
shopping centres and industrial areas.shopping centres and industrial areas.
Initial Cell Site PositioningInitial Cell Site Positioning
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Slide 86
Initial Cell Site PositioningInitial Cell Site Positioning
Some of the guidelines for cell placement include:Some of the guidelines for cell placement include:
A regular grid structure should be maintained as far as possible inorder to control interference.
Site roll out should commence from the urban areas where the smallersizes will be deployed and gradually move towards the sub-urban andresidential areas where larger sizes will be deployed.
At the transition between cells in urban areas and cells in suburbanareas, a cell size mid-way between the both sizes should be used to
further improve interference. For example, in making the transitionfrom Sharq to Mansouriya, cell size change should be gradual to keepinterference low.
Initial Cell Site PositioningInitial Cell Site Positioning
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Slide 87
Initial Cell Site PositioningInitial Cell Site Positioning
For coverage around highways or linear towns where continuousFor coverage around highways or linear towns where continuous
area coverage is not required, then cells with two sectors can bearea coverage is not required, then cells with two sectors can be
used as illustrated.used as illustrated.
Two sector sites along a major roadTwo sector sites along a major road
Initial Cell Site PositioningInitial Cell Site Positioning
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Slide 88
Initial Cell Site PositioningInitial Cell Site Positioning
Coverage in some isolated populationCoverage in some isolated population
centres or in mountainous regionscentres or in mountainous regionsmay be easily covered by an omni sitemay be easily covered by an omni site
instead of a sectored site since theinstead of a sectored site since the
increase in range offered by sectoredincrease in range offered by sectored
sites with directional antennas willsites with directional antennas willonly result in additional unpopulatedonly result in additional unpopulated
areas being covered. An example isareas being covered. An example is
the Ab-daly area. Using sectored sitesthe Ab-daly area. Using sectored sites
will cost more per site but will notwill cost more per site but will not
result in fewer sites being used.result in fewer sites being used.
Initial Cell Site PositioningInitial Cell Site Positioning
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Slide 89
Initial Cell Site PositioningInitial Cell Site Positioning
Antenna heights above sea level should beAntenna heights above sea level should be
kept constant as far as possible i.e. Antennaskept constant as far as possible i.e. Antennason relatively high terrain locations such ason relatively high terrain locations such as
Ahmadi should be lower compared to antennaAhmadi should be lower compared to antenna
heights used in South Sabahiya or Al Zawr.heights used in South Sabahiya or Al Zawr.
Stretched out cells should be avoided e.g.Stretched out cells should be avoided e.g.
MTC Site 103 which has considerableMTC Site 103 which has considerable
coverage across the sea to the Arabian Gulfcoverage across the sea to the Arabian Gulf
causes considerable interference in Sharq.causes considerable interference in Sharq.
re ct ons an tat st care c ons an a s caAnalysisAnalysis
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Slide 90
AnalysisAnalysis
After the deployment of cells, it is necessary to predictsignal level from each of the sites.
Most radio planning tools enable the prediction of signalstrength (or pathloss) over a circular area surrounding thesite.
To examine the effects of coverage and interference, each
site should be predicted over at least a 40 km radius withincities e.g. Sharq, Yarmouk and over at least 50 km area inrural and open areas such as Ahmadi
Traffic PlanningTraffic Planning
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Slide 91
Traffic PlanningTraffic Planning
Traffic Planning is the next stage afterTraffic Planning is the next stage after
sites have been positionedsites have been positioned The objective of traffic planning is toThe objective of traffic planning is to
determine the number of DRCUsdetermine the number of DRCUs
required for each cell for a givenrequired for each cell for a given
spectrum allocation, grade-of-servicespectrum allocation, grade-of-service
and traffic demand.and traffic demand.
An Erlang density map will have beenAn Erlang density map will have been
created either from marketing surveycreated either from marketing surveydata for new networks or from livedata for new networks or from live
data imported from the OMCdata imported from the OMC
Traffic PlanningTraffic Planning
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Slide 92
Traffic PlanningTraffic Planning
The traffic spreading process also requires the use
of clutter ratios. Clutter ratios enable the systemsengineer to weight traffic demand assignment inurban areas differently from that assigned to openareas or desert areas. It therefore introduces a non-uniform distribution of traffic which is more realistic
than uniform spreading. The clutter ratio for Urban and Business District
areas will be expected to be at least 8 times as highas the factor for Mixed Barren Land areas. Similarly,to prevent spreading of traffic to sea regions, the
clutter weighting for sea, ocean, streams andcanals should be set to 0.
Traffic PlanningTraffic Planning
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Slide 93
Traffic PlanningTraffic Planning
Traffic planning also involves moving traffic from one cell to anotherthrough cell antenna re-orientation in order to reduce the loading on
a cell.
In order to allow for anticipated expansion of the network, it iscustomary not to permit any one of the cells to have the maximumconfiguration of DRCUs allowed. For example, in the present MTCGSM system, each cell can accommodate a maximum of between 6and 7 DRCUs. If system plans permit the deployment of this
maximum figure at any of the sites, then any growth in traffic mayresult in congestion from day 1 and an immediate need to introduceanother un-planned site !
Traffic loading during planning should not exceed 90% of themaximum load carrying capability.
requency ss gnment anrequency ss gnmen anPlanningPlanning
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Slide 94
PlanningPlanning
The objective of frequency planning is to assign
carrier to cells in such a way as to ensure thatthe co-channel and adjacent interference levelsare kept below an acceptable threshold for goodcommunications.
The traditional way to allocate frequencies is todivide the available spectrum into frequencygroups. For example, MTC has access to 15 MHzof spectrum for its GSM system yielding a total of
75 channels. These have been divided into 12groups (because of the use of a 4/12 pattern)thus giving approximately 6-7 carriers per group.
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Slide 95
PlanningPlanning
Groups are usually designated A1, A2, A3 .....
D1, D2 and D3. The carriers in group A1 are atleast 12 channels apart from each other e.g.channels 51 and 63; similarly the channels ingroup A2 are also spaced apart by 12 channelse.g. 55 and 67. Groups with the same
alphabetic code such as A1, A2 and A3 have achannel separation of 4. Since these are alwaysco-sited, this guarantees that little adjacentchannel interference will occur.
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Slide 96
PlanningPlanningGroups Frequency Carriers
A1 51 63 75 87 99 111 123
A2 55 67 79 91 103 115
A3 59 71 83 95 107 119 124
B1 52 64 76 88 100 112
B2 56 68 80 92 104 116
B3 60 72 84 96 108 120
C1 53 65 77 89 101 113
C2 57 69 81 93 105 117
C3 61 73 85 97 109 121
D1 54 66 78 90 102 114D2 58 70 82 94 106 118
D3 62 74 86 98 110 122 50C3
q The channel numbering scheme is the same as that used for GSM. Note
that grouping is carried out by assigning channels in numerical order to
groups in the sequence A1, B1, C1, D1, A2, B2, C2, D2, A3, B3, C3, D3.
q The choice of A, B, C and D arises because the pattern is a 4 site repeat
pattern. The choice of 1, 2 and 3 arises because there are three cells
per site.
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Slide 97
PlanningPlanning
The 4 site / 3 cell repeat patternThe 4 site / 3 cell repeat pattern
guarantees just over 12 dB C/I (co-guarantees just over 12 dB C/I (co-channel) in 90% of locations.channel) in 90% of locations.
Two methods can be employed in theTwo methods can be employed in the
assignment of groups or carriers toassignment of groups or carriers to
the cells:the cells:
Manual or traditional frequency planning
Automatic frequency planning
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Slide 98
PlanningPlanning
With manual frequency planning, the assignment of carriersis done through a row and column approach whilst maintain aregular reuse. The systems engineer will be aided by theradio planning tool which will produce co-channel andadjacent channel interference maps. Advantage can be takenof the interference blocking of hills and mountains as well asthe antenna front-to-back ratio.
The frequency plan would also be expected to take intoaccount all carrier exceptions such as may occur at theborder of the country e.g. at the Kuwait-Saudi border, or suchas may occur due to other types of equipment in the area e.g.data link transmissions in Sharq area.
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Slide 99
PlanningPlanning
Automatic frequency planning carries out assignment
automatically without user intervention, provided acomplete set of inputs are supplied: Anticipated neighbours list
Allocated frequency spectrum
Minimum channel spacing between cells at a site
Minimum channel spacing within a cell
Minimum channel spacing between a cell and its neighbour Carrier exceptions at each cell
Number of required carriers for a cell (from traffic analysis)
Available frequency spectrum
Acceptable co-channel and adjacent channel interference thresholds
Automatic frequency planning does not make use offrequency groups. Instead carriers are assigned on anindividual basis.
utputs o t e ann ngu pu s o e ann ngProcessProcess
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Slide 100
ProcessProcess
The outputs of the radio planningThe outputs of the radio planning
process, which form part ofprocess, which form part ofmanagement reports, include themanagement reports, include the
following information:following information:
Summary roll-out coverage and subscriber
distribution for each yearThis will include:
Areas covered in each phase e.g. Sharq, Yarmouk
Percentage of total covered area in each phase
Percentage population in each phase
Overall number of sites in each phase
Overall number of cells for each phase
Overall number of transceivers required for each phase
Overall number of subscribers supported from each phase
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Slide 101
ProcessProcess
An example from a GSM networkAn example from a GSM network
planned for the Northern region ofplanned for the Northern region ofTaiwanTaiwanR o l l - O u t
P h a s eC o v e r e dA r e a
P e r c e n t a g eo f t o t a l
c o v e r e da r e a
P o p u l a t i o np e r c e n t a g e
N u m b e r o f s i t e s
N u m b e r o f t r a n s c e i v e r s
N u m b e r o f s u b s c r i b e r s
Y e a r 1 T a ip e i c ity ,C h i l ung c i t y ,
T a i p e ic o u n t y , T a o -Y u a n c o u n ty
3 2 % 8 3 % 1 9 8 1 3 8 8 2 2 5 ,0 0 0
Y e a r 3 W h o le o f N o r t he r n
R eg ion
1 0 0 % 1 0 0 % 2 5 4 1 7 6 1 3 0 0 ,0 0 0
Y e a r 5 W h o le o f
N o r t he r nR e g io n
1 0 0 % 1 0 0 % 3 2 1 2 2 9 0 4 0 0 ,0 0 0
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Slide 102
Processocess
The outputs of the planning processThe outputs of the planning process
which also form part of managementwhich also form part of managementreports include:reports include:
Detailed statistics on a city-by-city basisshowing
Number of subscribers Number of sites
Number of cells
Number of transceivers
On-street coverage area probability
In-building area probability On-street C/I performance
In-building C/I performance
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Slide 103
Process
An example from a GSM networkAn example from a GSM network
planned for the Northern region ofplanned for the Northern region ofTaiwanTaiwan
County/City Number of
Subscribers
Number of
Sites
Number of
cells
Number of
transceivers
On-street
coverage
C/I 15 dB
Taipei City 105,750 88 264 663 100% 91%
Taipei County 88,650 80 230 532 97% 87%
Chilung City 10,125 10 27 62 97% 98%
Tao-Yuan
County
20,475 20 57 131 97% 94%
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ocess
Information which will be passed to theInformation which will be passed to the
installation team on a site-by-site basis forinstallation team on a site-by-site basis forsystem roll-out includes the following:system roll-out includes the following:
Site Identification Code and name, if applicable
Number of sectors
Coordinates - easting and northing or latitude and longitude
City or county area Antenna height
Antenna tilt
Antenna orientation
Allocated frequency groups
Allocated frequency carriers
BCCH carrier