radio network planning(revised)
DESCRIPTION
RMPTRANSCRIPT
Wireless Network Planning
Mobile Research Institute Network
Planning & Optimization Department
Objective
After taking this course, you will be able to : know the planning details and what to collect
know how to make capacity planning
know how to make coverage planning
know steps to take and notice to be observed during site survey
know coverage emulation and frequency planning
Category
Network Planning Information Gathering
Capacity Planning
Coverage Planning
Site Distribution & Survey
Coverage Emulation
Frequency Planning
Network Planning Information Gathering
Material of mobile service forecast
Information Gathering
Wave transmitting environment survey
Diagnosis
demand analysis
Existing network equipment & operator profile
City planning material
Analysis of network traffic distribution
Network coverage and quality analysis
Interference diagnosis
●forecast of all kinds of phone users●user distribution, such as ratio of urban users to suburban users●opinion of operators towards user number forseen●comparison of user numbers among similar cities
●existing mobile user number and annual growth rate●ratio of urban user number to suburban user number ●configuration and distributing status of existing mobile network MSC, BSC and BTS.●recent traffic statistics report and drive test report of mobile network●operators’ appraisal towards existing network and also suggestions toward network development
●city: provincial & industrial cities, and seaport●city populace and agricultural populace●existing and future coverage of cities and suburbs●distribution of urban industrial zone, commercial zone, residential zone and traveling zone●construction and development plan of economic zone●status and developing plan of roads and transportation●maps including district maps and city planning maps
●terrain, plain, hilly terrain and hills●height and density of land building and high building distribution● road path, width and wood distribution
●urban industrial zone, commercial zone, residential zone, traveling zone and high tech park●distribution of high traffic density, medium traffic density and low traffic density
●investigation of coverage range, coverage quality and voice quality (DT)● statistics analysis of interface of A, Abis cobra and OMC
●distributing and using status of existing frequency ●whether channel to be used is occupied or interfered (clear frequency)
Network Planning Information Collection
Demand analysis
Frequency OtherTraffic ModelCapacityCoverage
limited
frequency
used
usable
bandwidth
and
frequency
band
frequency
resources
KPI
traffic
distributing
ratio
planning
area size
redundancy
and other
requirements
traffic
distributing
ratio
traffic
demand and
system
capacity
data traffic
model
User type
and rate of
data traffic
voice traffic
model
scheme of
operators/
existing
website
number and
site
configuration
transmitting
ambience
electronic
map exists
or bought?
Network Planning Information Collection
Network planning information collecting template
Microsoft Excel ¹¤×÷±í
Inadequate info
1. What is necessary information? 2. What is supplementary info?
?
Catalog
Network planning information collection
Capacity planning
Coverage planning
Site distribution and survey
Coverage emulation
Frequency planning
Capacity Planning
...
Defines the relation between call loss, channel number and traffic volume.
...
Call loss refers to calls dropped when the channels in one mobile telecommunication system are exhausted, then call can’t be put through and thus got lost. It’s also called blocked call. Radio call loss rate GOS is call block rate. According to the rules in Public Mobile Telephone Network Technology System, radio channel loss rate is less than 5% and less than 2% in traffic-dense area.
Traffic model is the fundamental of radio network planning that defines the value of important parameters that may affect system capacity including average busy-hour traffic of each user and call loss rate).
One Erlang refers to the traffic load either when a circuit is fully occupied for a hour or when two circuits are fully occupied for half an hour.
Traffic volume
Traffic is the total of telephone calls on one group of lines or trunk. Busy-hour traffic A is the maximum traffic on the busiest hour of system or line. A= a * b * t. Of which, a is everyday call times (originating and terminating) per user , b is busy-hour to day ratio( busy-hour traffic divided by daytime traffic), and t is average call duration. Suppose one user has calls for 6 times per day, each time lasts 2 minutes and b is 0.15. therefore, A=0.03Erl
Basic concepts
Erland
Call loss rate
Erlang B table
Traffic model
Capacity Planning Procedures
Set parameter value Get number of estimated site configured
Get capacity distributing rate
Get site distributing status and their latitude and longitude
Reach target in accordance with capacity planning
1 2 3 4 5Network sizeCapacity information
gatheringSite distributionTraffic distributing
analysisSite model and nu
mber
Capacity Planning
1 Capacity Info Gathering
Network type: GSM900, DCS1800, dual-band network or WLL network ? System capacity demand. That is, how many users in the system and how heavy the traffic is? Traffic model of the voice service? Equipment type: V2/V3? Model? Indoor or outdoor? DPCT applied in V3 or not? Rate of adopting
DPCT? Is data service required? EDG frequency? Data service penetration rate? Traffic model of data se
rvice? What is frequency resource range ? Is there frequency that are prohibited? Maximum site configu
ration is? Make forecast and investigation of traffic density distribution and define capacity distributing rate.
Capacity Planning
return
Traffic are mostly in big and medium-sized cities and especially in the downtown of the city. Even in this area, there are denser traffic areas. So if these factor are not taken into consideration during network construction, it will lead to the waste of equipment resource in mean-traffic area and inadequacy of dense-traffic capacity and thus affects network investment profit and service quality.Traffic distributing analysis is to categorize the planning area into areas of different service levels based on forecast and survey of traffic density distribution and use it as the foundation in site distributing planning.
2
Traffic distributing analysis
扇面 141%
扇面 226%
扇面 315%
扇面 411%
扇面 57%
●how many phases and what is the ratio of users in
each phase
●what is the planning area range and the traffic
distributing ratio in DU/MU/SU/RU.
●Provide existing sites and their configuration and
performance statistics report data
Capacity planning
2
Traffic distributing analysis
Service level : by radio transmitting environmentⅠ
Area Topographic features
Denseurban
Average height of surrounding buildings is more than 30 metres (over 10 storey) and average distance between buildings is 10-20 metres. Usually the buildings are crowded around the site with the height of 10-20 stories and the ambient roads are not considerablly wide.
urbanAverage height of surrounding buildings is about 15-30 metres (5-9 storey) and average distance between buildings is 10-20 metres. The buildings are evenly distributed around the site. Mostly are below 9 stories and some are over 9 stories and the ambient roads are not considerably wide.
suburb
Average height of surrounding buildings is about 10-15 metres (3-5 storey) and average distance between buildings is 30-50 metres. The buildings are evenly distributed around the site. Mostly are 3-4 stories and some are over 4 stories. Roads around are wide.
ruralAverage height of surrounding buildings is below 10 metres. They are dispersed and mainly are 1-2 storey high. There are spacious space between.
Capacity planning
2
Traffic Distributing AnalysisService level : by service distributing areaⅡ
Area Distribution Features
Dense urbanTraffic is heavy and rate shall be high,
which is the focus of data service development
Mean urbanTraffic is relatively heavy and rate should
be comparatively high. Data service is required
suburbTraffic is low and only low-speed and data
service are provided
ruralTraffic is quite low. Site is for coverage
purpose and consequently data service quality are not ensured.
Radio transmitting
environment and service
distributing factors should all
be taken into consideration.
Capacity Planning
return
3Site Model & Number Estimate maximum configuration and capacity of each site based on frequency resources
and frequency reusing mode. Total traffic volume divided by site capacity is site number. Number of sites configured in different areas of each phase. Channel number (service channel number and control channel number) of a cell or site
as well as their traffic volume and user number. Totaling of sites capacity. Also called network capacity.
Total Traffic
Traffic per site
Start
Frequency resources
Capacity of each cell
Capacity per siteSite configuration
& number
Frequency reuse method
Maximum configuration
Channel planning & data service
ERL B table
Traffic model
Model configuration
Traffic volume & distributing ratio
Network Scale Coverage Planning
Capacity Planning
3Model & Site Nu
mber
Coverage Planning
Capacity Planning
Network Scale
Capacity planning is to
add or reduce sites based
on radio coverage
planning and analysis.
Capacity planning is a
repeated, gradual process
helping to decide site
number and model
distribution.
Capacity Planning
Catalog
Network Planning Information Gathering
Capacity Planning
Coverage Planning
Site Distribution & Survey
Coverage Emulation
Frequency Planning
Coverage Planning
Process
Set parameter Get estimated
coverage radius of each site
Get allowable max path loss
Get information of distribution as well as latitude & longitude of sites
Target the goal of coverage planning
1 2 3 4 5
Network scaleSet network parameter
Site distribu-tion & coverage e
mulationLink budget Coverage radius
estimate
1
Set network parameter
Network category: GSM900,DCS1800, dual-band or WLL network? Equipment type: V2 or V3? Model? Indoor or outdoor? Apply DPCT in V3? DPCT ratio? Carrier Transmission power is 40W , 60W , 80W? Are data service required? EDGE carrier fr
equency ? Antenna model: antenna gains, horizontal and vertical beam width, antenna downtilt, polariz
ation mode and electrical downtilt etc. Antenna parameter: antenna available height, directional angle and downtile. Apply tower top amplifier? Feeder type: 7/8 feeder or 15/8 feeder? Maximum site configuration is? Are there special requirements toward configuration of comb
ining and distribution unit? What is KPI? What is level and area coverage rate? Which new technology will be adopted in V
3 site, DDT? IRC? or FWDR?
Coverage Planning
return
2
Link Budget
Definition: analyze the factors that may affect uplink and downlink signaling transmission, evaluate the coverage capacity of the system and get maximum transmission loss allowed by the link with call quality ensured.
Object: Purpose of analysis and computing of both uplink and downlink power is to get maximum available power of the site, avoid invalid downlink coverage, reduce interference and system noise, which lays a foundation for quality service.
Get allowable maximum indoor & outdoor path loss of uplink and downlink according to budget of uplink and downlink.
The smaller of allowable maximum indoor & outdoor path loss of uplink and downlink is considered to be the allowed maximum indoor & outdoor path loss of the same efficiency and set it to be the loss when estimating radius coverage.
Uplink Downlink
Coverage Planning
2
Link budget
PAPA
Feeder loss Transmission loss
Antenna gain
Penetration loss
Site sensitivity
Fading margin
Body loss
MS power
Put it in a simple way, link budget is the computing of loss and gains on one telecommunication link.
Coverage Planning
2
Link Budget
template
Losses
Margin reservation
Gains
Network Type & Equipment
Link Budget
Transmission power and reception sensitivity of MS/BTS
Maximum site configuration affect the selection of combining and distribution unit
Fast fading margin Slow fading margin Interference magin
Site antenna gain MS antenna gain TMA gain
Path loss Body loss Apartmen
t loss Vegetatio
n loss
Building penetration loss
Feeder and connector loss
Combiner and splitter loss
Microsoft Excel ¹¤×÷±í
Coverage Planning
Complying with GSM protocol , transmission power are showed as follows :
losses
margin reservation
gains
equipment
link budget
2
Link Budget
Power class GSM 900 Nominal
Maximum output p
ower
DCS 1800 Nomin
al Maximum output
power
PCS 1900 Nomina
l Maximum output
power
1 1 W (30 dBm) 1 W (30 dBm)
2 8 W (39 dBm) 0.25 W (24 dBm) 0.25 W (24 dBm)
3 5 W (37 dBm) 4 W (36 dBm) 2 W (33 dBm)
4 2 W (33 dBm)
5 0.8 W (29 dBm)
Coverage Planning
2
Link Budget Transmission power, Reception sensibility and biggest site configuration of GSM BTS V2 and V3 are as follows:
Series Moduling mode Transmission power Reception sensibility Biggest site config
BTS V3
B8018GMSK 60 W 47.78 dBm
‑112 dBm S18/18/188PSK 31 W 45 dBm
B8112GMSK 60 W 47.78 dBm
‑112 dBm S12/12/128PSK 31 W 45 dBm
M8202GMSK 30 W 44.78 dBm
-110 dBm S2/2/2 or O6 8PSK 20 W 43 dBm
BTS V2
GMSK 40W 46 dBm -110 dBm S12/12/12
GMSK 80W 49 dBm -110 dBm S6/6/6
8PSK 30W 44.78 dBm -110 dBm S12/12/12
(EDGE)
GMSK 60W 47.7 dBm -110 dBm S12/12/12
OB06 GMSK 40W 46 dBm -110 dBm S6/6/6
BS30 GMSK 40W 46 dBm -110 dBm S2/2/2
BS21GMSK 40W 46 dBm -110 dBm S2/2/2
GMSK 80W 49 dBm ‑112 dBm S1/1/1
Equipment
Coverage Planning
losses
Margin resservation
gains
equipmentbudget
2
Link Budget
●Path loss
●Body loss
●Compartment loss
●Vegetation loss
●Building penetration loss
●Feeder and connector loss
●Combining and distributing unit loss
Coverage Planning
Path lossRadio wave loss caused by the transmission distance.
Body lossWhen the phone is at waist or shoulder, the signaling is lower than when antenna is several wavelength far from body. As for voice service, body is supposed to be 3 Db; for data service, 0dB.
Compartment lossUsually it is 8~10dB.
Vegetation loss
Vegetation loss is related to density of the forest, leaf shape (conifer and board leave), forest height and the distance between forest and antenna. Inside the forest, the loss of 900MHz is 0.2dB/m; the loss of 1800MHz is 0.3dB/m; Through forest or diffraction, the loss is 20dB/dec; For there are forest around the antenna and the antenna is lower than the forest, around 10dB
Building penetration lossBuilding penetration loss is the loss caused when wave passing through the construction. It equals to the difference between average signaling level inside and outside the construction. Averagely it’s 10 – 20 dB , relying on building material and thickness.
Losses
2
Link Budget
Area 900M loss ( dB ) 1800M loss ( dB ) Dense urban 18 ~ 22 23 ~ 27Mean urban 15 ~ 20 20 ~ 25 Suburb & rural
10 ~ 15 15 ~ 20
Coverage Planning
Feeder loss Type loss ( dB/100m ) 900M 1800/1900M
1/2 soft jumper 7.22 11.37/8 feeder 3.89 6.1515/8 feeder 2.34 3.84
Losses
2
Link Budget
Combining & splitter loss( 1 ) CDU ( Combiner Distribution Unit )宽带合路器
LNA含分路器
收发双工器
ANT
TX1
TX2
RX1RX2RX3RX4
ERX1
ERX2
ETX
Coverage Planning
Losses
2
Link Budget
Combiner & splitter loss( 2 ) ECDU ( Duplexer & splitter )
ANTD
RX2
RXD1
RXD2
RX1
收发双工器
ITX
LNA含分路器
LNA含分路器
分集接收滤波器
ANT
( 3 ) RDU ( Receiver Distribution Unit )
Coverage Planning
TX3
RX2
RX3
RX4
分路器
分路器
RX1
合路器
合路器TX4
TX2
TX1OTX1OTX2
ERX1ERX2
Losses
2
Link Budget
Combiner & splitter loss
( 4 ) CEU ( Combiner Extension Unit )
( 5 ) CENU ( Combiner Extension Net Unit )TX3
RX2
RX3
RX4
分路器
分路器
RX1
合路器
合路器
TX4
TX2TX1
OTX1OTX2
ERX1ERX2
TX5TX6
TX3
RX5~RX8分路器
分路器
RX1~RX4
合路器
合路器
TX4
TX2TX1
OTX1OTX2
ERX1ERX2
TX5TX6
CENU CENU/2
Coverage Planning
Losses
2
Link Budget
Combiner & Splitter loss
Unit (900M) Insertion loss
CDUG 4.4dBCEUG 3.5dBCENG 5.3dB
CENG/2 5.3dBECDU 0.9-1.0dB
Unit(1800M) Insertion loss
CDUD 4.6dBCEUD 3.6dBCEND 5.5dB
CEND/2 5.5dBECDU 0.9-1.0dB
Coverage Planning
Losses2
Link Budget
Combiner & splitter loss
Configuration of Carrier number, combiner & splitter and antenna in one cell in BTS V2(80W TRX) are as follows:
TRXnumb
er
Antenna number &
configuration CDU RDU CEU
Remark
1 2 , TX/RX , RX 1 1 -CDU need special treatment:
connect TX1 interface with TX interface of
combiner and inactivate TX2
2 2 , TX/RX , TX/RX 2 - -CDU need special treatment:
connect TX1 interface with TX interface of
combiner and inactivate TX2
3~4 2 , TX/RX , TX/RX 2 - -5~6 2 , TX/RX , TX/RX 2 - 2
Coverage Planning
Losses
2
Link Budget
Combiner & splitter loss
Configuration of Carrier number, combiner & splitter and antenna in one cell in ZXG10 B8018
TRX number
Antenna number & config CDU ECDU CEU CENU Remark
14 , ( 2 TX/RX , 2 RX ) - 2 - -2 ,( 2 TX/RX ) 2 - - - CDU+TMA for extension
22 , TX/RX , TX/RX 2 - - - Combiner for easy extension
2 , TX/RX , TX/RX 2 - - - Without Combiner. TMA. large coverage
3~4 2 , TX/RX , TX/RX 2 - - -
5~62 , TX/RX , TX/RX 2 - 1 - For easy extension,
imbalance carrier frequency
2 , TX/RX , TX/RX 2 - - 1 To balance carrier frequency7~8 2 , TX/RX , TX/RX 2 - 2 -
Coverage Planning
Losses
2
Link Budget
Combiner & splitter loss
Configuration of Carrier number, combiner & splitter and antenna in one cell in ZXG10 B8112
TRX number
Antenna number & config
CDU
ECDU CEU CEN
URemark
1 2 ,( 2 TX/RX ) - 1 - -
22 , TX/RX , TX/RX 2 - - - combiner for easy extension
2 , TX/RX , TX/RX 2 - - - Without combiner. TMA. Large coverage
3~4 2 , TX/RX , TX/RX 2 - - -
5~62 , TX/RX , TX/RX 2 - 1 - For easy extension. Imbalance
carrier frequency
2 , TX/RX , TX/RX 2 - - 1 Balance carrier frequency
7~8 2 , TX/RX , TX/RX 2 - 2 -9~12 2 , TX/RX , TX/RX 2 - - 2
Coverage Planning
losses
margin reservation
gains
euipmentlink budget
2
Link Budget
Site antenna gainAntenna model selection should based on actual condition.
Area Antenna gain ( dBi )urban 15.5
suburb 15.5~17
rural 17~18
Express way or long & narrow valley
18~21
Hills and highland 17~18
MS antenna gainusually is 0
remark : special attention should be paid to antenna gain in MS in GSM WLL network Antenna may be indoor, outside door or on the roof. So antenna gain and height should be examined, which will affect coverage greatly.
TMA gain
Coverage Planning
losses
margin reservation
gains
equipmentLink budget
2
Link Budget
Fast fading & deterioration storageFast fading is due to stationary wave field because of the multi-path interference caused by the reflection on path of scatters (building) or nature obstacles (mainly forest) within 50-100 wavelength around MS. When MS goes through this station wave field, received signaling becomes fading and signaling level fluctuates greatly. fast fading & deterioration reservation is the additional received level in receiver noise condition when multi-path effect and factitious noise (car arc interference ) exists.walking : 2.0--5.0dB fast moving : 0dBIn GSM system, fast fading amount of voice and data service is supposed to be 3dB.
Interference marginIn Gsm system, there are intra-frequency interference, inter-frequency interference, intermodulation interference, and interference from vicinity to beyond. These interference will affect link budget. The interference margin is generally supposed to be 3dB.
Coverage Planning
losses
margin reservation
gains
equipmentLink budget
2
Link Budget
Slow fading margin ( fading margin )Slow fading is due to shadow effect caused by signaling interference from ambient buildings or terrain. The interference will attenuate the received signaling, which is called shadow fading.
To ensure that site signaling can cover cell edge at certain rate. It’s necessary for the site to preserve some transmission power called fading margin to counteract shadow fading. Generally shadow fading follows logarithm normal distribution. Shadow fading margin should base on operator demand of shadow fading variance and margin coverage probability.slow fading standard deviation is related to transmission condition of electromagnetic wave. In cities, it’s about 8~10 Db, while in suburbs or rural areas , 6 ~ 8dB.For instance : city : fading standard deviation is 8dB, marginal coverage probability is 90% and shadow fading margin is 10.3dB
countries: fading standard deviation is 8dB, marginal coverage probability is 75% and shadow fading margin is 5.4dB
Marginal coverage probability(%)
70 75 80 85 90 95 98
slow fading margin/dB 0.53σ 0.68σ 0.85σ 1.04σ 1.29σ 1.65σ 2.06σ
Coverage Planning
2Link Budget
Parameter Symbol
MS transmitting power ABody loss B
Building loss C MS reception sensibility D
MS antenna gain E TMA gain F
diversity gain GFeeder loss H
combiner/divider unit loss I
fast fading and deterioration reservation J
fading margin K noise margin L
path loss indoor M=A-B-C-D+E+F+G-H-I-J-K-L
path loss outdoor N=M+C
It’s normal that loss difference between uplink and downlink is 3-5dB; It’s considered to be imbalance of uplink and downlink if loss difference is over 10, when link budget should be modified.
Coverage Planning
return
3Coverage radi
us estimate
Basis to estimate coverage radius● maximum allowable path loss when uplink and downlink keep bal
ance
●propagation model Okumura-Hata model Cost231-Hata model Universal model Cost231-Walfish-Ikegami model
Coverage radiusestimate
Max allowable loss Propagation model selection
Coverage Planning
return
4Site distribution & coverage emulation
Sitedistribution
Electronic map/Mapinfo mapPlanning area sizeplanning area(Polygon) partitionPlanning site numberLink budget radius estimate
Distribution mapDistribution infoDistribution latitude & longitude
****Input Output
Coverage planning
return
4Site distribution & coverage emulation
Coverage &emulation
****Input Output
Electronic mapPlanning mapPolygonlatitude & longitude of sitesAntenna height/direction angleAntenna selectionPropagation modelLink budgetExisting network data
Site distribution mapSite coverage effect mapHeight info mapExisting network coverage mapCoverage probability statistics table
Coverage planning
return
5
Network scale
Coverage planning
Capacity planning
Network scale
Coverage planning
Catalog
Network planning info gathering
Capacity planning
Site distribution & survey
Coverage emulation
Frequency planning
Site distribution & survey
coverage planning + capacity planning =>site scale
Distribute site on Mapinfo or PLANET/EET map, set site theoretic location, and get latitude & longitude and other para of sites
Based on theoretic latitude & lon
gitude of sites, make sites surve
y. According to practical traffic di
stribution, coverage requirement,
ambient construction environme
nt, natural environment, power s
upply, propagation supply, and la
nd lease , decide site location an
d feeder design, including site lo
cation, site type & location, anten
na selection, height, direction an
gle, downtilt, combiner & splitter,
tower top amplifier and feeder et
c.
Site survey is key to site distribution including optical measurement, spectrum measurement and site location investigation.
Optical measurement
▪ Ambient construction environment and natural environment Spectrum measurement
▪ Electromagnetism environment Site survey
▪ Installation condition of antenna and equipment
▪ Power and transmission supply
Preparation●familiarize with the engineering by collecting materials relating to the project inc
luding : Engineering files, background material, existing network situation, map
and configuration list
●Get tools ready Digital cameral, GPS satellite receiver, compass, ruler and pc.
Site distribution & survey
Location selection When selecting location, take the following aspects into consideration
Previous Network condition Population distribution and habits City layout and distribution Main streets and traffic volume Natural environment such as Hills, lakes, rivers and coastline Growing trend
Select high traffic area and dense population area
populaceTraffic distribution
Customer flow trend
Principles of site selection
Surrounding environmentSignaling transmission quality
Careful select high hills, radar, radio
station, filling station, forest and power plant
Site distribution & survey
Site selection Main principles to select sites
Site should be at the best place of regular mesh with deviation less than a quarter of the site radius. Select existing facilities for cost saving and period reduction purpose on the premise that it doesn’t affe
ct site distribution. City skirt and high-elevated hills(100 m or 300 m higher than city construction) in suburbs are not suppos
ed to be sites, as first to control coverage scope, second to make construction and maintenance easier. Newly-constructed sites should better be at place where transportation is convenient, has ample power
supply, environment is safe and has less farmland. Avoid construct sites near high power radio transmitter, radar station or other interferer. Better far from forest to avoid fast fading of received signaling. Pay attention to the effect of signaling reflection and dispersion when in hills, steep slopes, dense lake ar
ea, mountainous region and high metallic buildings. When in cities, utilize the height of the building to realize division of network hiberarchy. There are less sites in the initial stage of network construction, so good coverage of key areas should be
guaranteed.
Site distribution and survey
AEM design
CDU
Feeder design
Function of transceiver duplex , transmission signaling combining, filtering and receiving signaling filter, low noise amplifier and splitter is encouraged. TMA feed circuit is provided. One unit uses one antenna for multiple signaling transmitting and receiving.
AntennaHeight, direction
angleFrequency range, gainPolarizationHorizontal and
vertical 3dB beam widthDown tilt
To enable sensibility of site reception system. TMA is optional, and can be selected based on system band. CDU site can use simplex TMA and triplex; combiner site. Site adopting CDU can use simplex or duplex TMA, while site adopting combiner can use duplex TMA.
TMA
Feeder
For 900MHz , 5/4″ feeder when feed length is over 80m ;For 1800MHz , 5/4″ feeder when feed length is over 50m ;
Site distribution & survey
AEM Design
Major guidelines for network planning are: Frequency Range Gain Polarization Horizontal/Vertical half-power beam width Down tilt
The following is antenna direction map of Kathrein 739649
Site distribution & survey
AEM Design
Antenna selection is vital to network quality.
Select the antenna according to the coverage of service area, service quality
demand, traffic distribution, and topography, coverage of the whole network
and interference condition should also be considered.
Environment is classified into the following based on topography and traffic. Urban area, suburb, rural area, road, mountainous area , offshore, tunnel and indoor
BTS in city
a select directional antenna with horizontal half-power of 60 ~ 65°b select medium gain antenna of about 15dBic best to select antenna with electrical downtilt of 3 ~ 6°d recommended to select dual-polarized antenna
BTS in suburb
a select direction antenna with horizontal half-power of 65°or 90°b generally select medium or high gain antennac preset downtilt or not based on actual conditiond select dual polarized or vertical polarized antenna
Site distribution & survey
Rural sites
a 、 select directional antenna of 90° 、 120°or all way antennab 、 Gain of directional antenna selected is higher than normal ( 16 ~ 18dB
i ) c 、 generally don’t select downtilt antenna. For high sites, zero filling antenn
a is the best choice. d 、 vertical polarized antenna is recommended
Road Sites
a 、 generally select narrow-beam, high-antenna directional antenna. Select 8-shape antenna, all-way antenna or deformation all-way antenna based on actual condition
b 、 generally don’t select downtilt antenna because road site has higher requirements toward coverage distance.
c 、 vertical polarized antenna is recommended.d 、 front-to-back radio ratio of selected directional antenna should not be hi
gh.
AEM Design
Site distribution & survey
AEM Design AEM design
principle Antenna of different cell of the same site can be different due to installation conveniences or cell planning requirements.
For flat rural area, valid height of antenna is generally 25m. For suburbs, antenna height can be elevated to 40m. Antenna overheight will reduce coverage level near the antenna especially for omni antenna Antenna overheight will easily cause problems affecting network quality like severe cross-area cover
age, co-channel interference or adjacent-channel interference. Design principle of Antenna direction angle
From the network’s point of view, directional angel of three-sectored area of rural sites should be the same. Adjustment of antenna directional angel can be made based on coverage target in the neighborhood of rural and suburban area, arteries and solo site in suburb.
Antenna main lobe should direct at dense traffic area to enable signaling strength and to elevate call quality.
Main lobe deviate from co-frequency cell to control interference effectively. Intersection coverage depth of rural adjacent sectored antennas should not exceed 10%. Intersection coverage of suburban and commune adjacent cells shouldn’t be too deep and
inclination of adjacent sectored antenna of the same site should not less than 90%. Antenna lobe of dense rural area should avoid opposing straight street for cross-area
coverage.
Site distribution & survey
AEM Design Design principles of antenna downtilt
Antenna beam tilt is basic technique of enhancing frequency reuse ability.
Antenna beam tilt technique can control coverage range to reduce interference in the system.
Antenna downtilt angle depends on actual condition in order to reduce interference between co-frequency cells and to
guarantee coverage requirements.
Downtilt design should take sites transmission power, antenna height, cell coverage range and radio transmission env
ironment into consideration. Antenna beam tilt can either use electrical or mechanical mode. Electrical tilt is fixed relating to antenna model sele
cted and mechanical tile is adjustable but generally not beyond limited by installation component and radio signaling broadcasting features
Different surface radiation will be generated using electrical downtilt or mechanical mode. When downtile angle is small, difference is small. When angle gets bigger, difference becomes more obvious
Site distribution & survey
AEM Design Antenna isolation
There must be isolation between receiver and transmitter of the site. Antenna isolation degree: fading of signaling from one port of antenna to another when ant
ennas are installed. For GSM system, isolation degree between two transmitting antenna and between transmit
ting antenna and receiving antenna should be no less than 32 Db ▪ Lv=28+40log(k/λ)(dB) (When antenna is vertically distributed)▪ Lv=22+20log(d/λ)-(G1+G2)-(S1+S2)(dB) (When antenna is horizontal distributed)
Fulfill the spacing requirement of diversity gain Distance between two receiving antenna is 12 ~ 18λwhen antenna is diversified by space. Distance between diversity antenna shall be greater when antenna is higher. Generally distan
ce between diversity antenna is 0.11 times of available antenna height. To achieve the same effect, distance of vertical diversity must be 5 or 6 times of vertical divers
ity. To reduce the interaction of the two antennas, horizontal distance of diversity antenna should
be over 3 m with antenna at whatever available height
Site Distribution & Survey
Catalog
Network Planning Information Collection
Capacity Planning
Coverage Planning
Site Distribution & Survey
Coverage Emulation
Frequency Planning
Coverage Emulation
Coverageemulation
Electronic mapPlanning areaPolygonLatitude & longitude of sitesAntenna height & direction angelAntenna modelLink budgetExisting network data
Sites distribution mapSite coverage effect mapHeight information mapExisting network coverage mapCoverage rate statistics table
****Input Output
Coverage Emulation
Catalog
Network Planning Information Collection
Capacity Planning
Site Distribution & Survey
Coverage Emulation
Frequency Planning
GSM900Uplink 890 915 MHzDownlink 935 960 MHzduplex separation is 45MHz , carrier frequency separation is 200KHz
EGSMUplink 880 890 MHzDownlink 935 935 MHzduplex separation is 45MHz , carrier frequency separation is 200KHz
DCS1800Uplink 1710 1785 MHzDownlink 1805 1880 MHz duplex separation is 95MHz , carrier frequency separation is 200KHz
Frequency Planning
P-GSM900 Fl (n) = 890 + 0.2n MHz
Fu (n) = Fl(n) + 45 MHz 1 n 124
n stands for ARFCN
E-GSM900Fl (n) = 890 + 0.2(n-1024) 975 n 1023
Fu (n) = Fl(n) + 45 MHz 0 n 124
DCS1800Fl (n) = 1710.2 + 0.2(n-512) MHz
Fu (n) = Fl(n) + 95 MHz 512 n 885
GSM Working Frequency Band GSM Frequency Band Serial Number
Frequency Planning
Co-frequency interference C/I :C/I , is the value of interference. When different cells use the same frequency, another cell may bring interference to the serving cell. Conforming to GSM criterion, C/I >9dB. In actual engineering, C/I>12dB
Adjacent-frequency interference C/A :C/A is the rate between the two channel when adopting frequency duplex pattern, adjacent channel will bring interference to the channel of the serving cell. Conforming to GSM criterion, C/A>-9dB. In actual engineering, C/A>-6dB.
whatever method, it should meet the following requirements taking different transmission condition, different multiplex mode, multiple interfering factor into consideration.
co-channel interference protection rate C/I≥9dBadjacent channel interference protection rate C/I ≥ - 9dB adjacent channel interference protection rate(400KHz) C/I≥ - 41dB
Definition of Interference of Co-frequency & Interference of Adjacent Frequency Frequency Planning
Frequency Planning
Frequency Planning
GSM commonly-used frequency multiplex pattern
A3
D2B1
D1
D3
C1B3
C2
B2
C3
A1
A2
A3
D2B1
D1
D3
C1B3
C2
B2
C3
A1
A2
A3
B1
B3B2
A1
A2
A3
B1
A1
A2A3
D2B1
D1
D3
A1
A2
A1
A3
D2B1
D1
D3
C1B3
C2
B2
C3
A1
A2
“4×3”multiplexSuppose cellular hexagon side length is 1, intergrating interference model, we will get:
dB
dBIC
18)2.7(2)8(
2log10
)(
44
4
18dB>12dB
Frequency Planning
A3
C2B1
C1
C3
B3B2
A1
A2
A3
C2B1
C1
C3
B3B2
A1
A2A3
C2B1
C1
C3
B3B2
A1
A2
A3 C1
A1
A2
A3
C2B1
C1
C3
B3B2
A1
A2
A3 C1
A1
A2
A3
B1
B3B2
A1
A2
Frequency Planning
GSM commonly-used frequency multiplex pattern
“3×3”multiplexSuppose cellular hexagon length is 1, integrating interference model, we can get:
dB
dBIC
3.13)57.5(2)7(2
2log10
)(
44
4
13.3dB>12dB
Frequency Planning
Control channel planning
Computing of control channel numberuse M/G/N/N model as traffic model of control channel.Suppose SDCCH call average processing time is 3 second, average processing time of place upgrade is 9 second, user busy-hour call times is 2BHCA, traffic volume of users on SDCCH will be:
(3×2+9)/3600=0.0042 ErlangWhen GOS=2%, capacity of 4SDCCH is 1.092Erlang , user volume is
(1.092/0.0042=260 户 ) ×0.025 Erlang=6.5ErlangBy referring to Erlang-B table, 12 TCH(2TRX) are needed.When GOS=2%, capacity of 8SDCCH is 3.627 Erlang , user volume is
8 (3.627/0.0042=863 户 ) ×0.025 Erlang=21.6Erlang By referring to Erlang-B table, 30 TCH(2TRX) are needed.Generally, we can get the maximum site configuration according to frequency resource and selected frequency multiplex. In planning , select suitable site configuration. Control channel number can be gotten using ERL B table.
$
Frequency Planning
PDCH Planning
Fix traffic model of data service
If GPRS/EDGE service are supported ,please
provide
GPRS user (%) 20%
EDGE user (%) 100%
Busy-hour throughput per user ( bps/sub ) 220Or provide : monthly traffic per user (MB/Month)
Monthly valid days ( days/Month ) busy-hour rate ( hours/day )
Penetrate percentage of data service 20%Attach percentage 10%
PDP Context Active percentage 20%Other null
User data service traffic
( user number ) X ( Penetrate percentage ) X ( Attach percentage ) X ( PDP Context Active percentage ) X ( monthly traffic per user )
Frequency Planning
PDCH Planning
Fix coding mode rate of data service
GPRS coding mode
Bear velocity of Um IP layer
Applicationrate
Average bearing velocity of Um IP layer
CS-1 (Kbps) 6.4 0.2
10.454CS-2 (Kbps) 9.41 0.3CS-3 (Kbps) 11.11 0.3CS-4 (Kbps) 15.09 0.2
Compute PDCH number of data service of each cell with different configuration.
In this way, we can get average velocity of 9 coding type of EDGE
( data service traffic of cell user ) / ( average velocity of data service )
$
Frequency Planning
Carrier chann
el SDCCH
Controlchanne
lSurpluschannel
TCH user
traffic/cell
PDCH channel TCH ERL
TCH user
1 8 SDCCH/4 1 7 117 2.0592 1 2.28 911 8 SDCCH/8 2 6 91 1.6016 1 1.66 662 16 SDCCH/8 2 14 327 5.7552 1 7.4 2963 24 SDCCH/8 2 22 595 10.472 2 13.18 527
4 322*SDCCH/
8 3 29 841 14.8016 2 19.27 770
5 402*SDCCH/
8 3 37 1130 19.888 3 25.53 1021
6 482*SDCCH/
8 3 45 1424 25.0624 4 31.92 1276
7 563*SDCCH/
8 4 52 1685 29.656 4 38.39 1535
8 643*SDCCH/
8 4 60 1985 34.936 4 45.87 1834
PDCH Planning
PDCH planning data of data service
Frequency Planning
TCH Planning
Basic Discipline Carriers configured in cells in a certain site shall not be co-channel or adjacent channel. Opposite cell should not co-channel and avoid adjacent channel. High hill shall not be considered as neighboring site while broad water shall be considered as neighboring sit
e. Concerning antenna height and complexity of transmission environment, carriers in opposite & cells of nearb
y sites should avoid co-channel. ( 含斜对 ); Focus on co-channel reuse. Avoid using the same BCCH with the same BSIC in neighboring areas. Verify and adjust frequency using planning forecast software.
Frequency Planning
□ Configuration of neighboring cells– GSM system is centered on cells and have at most two-level handover relationship externally.– For a stable GSM system, modify unreasonable handover cell in the planning according – to data in drive test.– Cells handed over shall not be co-channel.– Switch shall be mutual, not undirectional – There shalln’t be two handover cells with the same BCCH with the same BSIC. – There shalln’t be two handover cells with the same BCCH with the same BSIC– cell switch selection shalln’t be two many or too little. Two level is best especially– for cells covering road or railway.
Frequency PlanningTCH Planning
Preserve frequency. When we make the frequency planning, we seldom preserve frequency especially for frequency-lack telecom engineering. In fact, there are lots of advantages to preserve frequency such as using as frequency in the test, as replacement frequency in the interference , as cellular frequency in dense-traffic region. 28 frequency is used in phase 5 engineering of Chongqin Telecom with frequency No.98 preserved. Frequency No. 98 and No. 108 will be preserved in Phase 6. At least one frequency will be preserved in frequency planning.
Allocate BCCH frequency and TCH frequency. Generally BCCH should be allocated greater continuous frequency number.
Assign frequency to different areas. Assign frequency for sites in different areas such as urban, suburb and rural. Focus should be put on cities to avoid interference. Make planning in urban areas before in suburbs and rural areas. Divide urban area into different areas when there are many sites.
Check manually. Check manually after frequency assignment via automatic frequency planning. Modify frequency assignment condition or modify frequency manually if frequency is unsuitable.
Pay attention to the following in the process of GSM frequency planning:
Frequency Planning
GSM Network Planning
info collection
capacity planning
coverage planning
site distri- bution & survey
frequency planning
radio network
Action/reaction