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3G Network Planning Study with Monte-CarloSimulation
3G Network PlanningStudy with Monte-Carlo Simulation
Nuno Daniel Cardoso
Portugal Telecom Inovação S.A.
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3G Network Planning Study with Monte-CarloSimulation
Overviewn Objectives.n Simulation scenario description.n Load impact on coverage probability.n Noise rise limit.n Handover margin.n BS Antenna tilt angle.n BS Antenna height.n Downlink handover gain.n Pilot power.n BS sector aperture.n Voice vs. video impact.
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3G Network Planning Study with Monte-CarloSimulation
Objectives of the Performed Workn Study UMTS cellular planning via Monte-
Carlo simulation using real terraindatabase information.
n Understand the impact of some WCDMAparameters in the system performance.
n Evaluate the effects of using differentservices in the same cell.
n Gain experience in this new technology tobetter predict and understand the systembehavior during the deployment phase.
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3G Network Planning Study with Monte-CarloSimulation
Terrain Morphology and Cells Layout
Jersey Island – irregular terrain leads to dissimilarcell sizes.
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3G Network Planning Study with Monte-CarloSimulation
Parameters Assessed by Simulation
Parameter Default Other values
Noise rise limit (dB) - limit of the noise rise allowed in the system
6 3 None
Handover margin (dB) - margin related to the highest signal strength
6 3 9
BS antenna tilt (º) - angle of the antenna down tilting
0 3 6
BS antenna height (m) - height of the antenna from the ground
25 10 40
Downlink soft handover gain (dB) - soft handover gain in the downlink
2 -2 0
Pilot power (dBm) - power of the pilot channel
30 27 33
BS antenna aperture (º) - angle of the half power beam width
85 60
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3G Network Planning Study with Monte-CarloSimulation
Input Simulation Parameters
Other simulation parameters needed for thesimulator.
Parameter Value
Maximum BS Tx power (dBm) 43
Maximum Tx power per connection (dBm) 35
Common channels power (dBm) 30
Simulation geographical resolution (m) 50
Terminal background noise (dBm) -99
BS background noise (dBm) -103
Active set size 3
Orthogonality factor 0,7
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3G Network Planning Study with Monte-CarloSimulation
Services characteristics
Service/Terminal Voice/ Handheld
144 kbps/PDA video
Type of service Circuit switched
Circuit switched
Bit rate (kbps) 12 144
Mobile speed (km/h) 120 120
Downlink Eb/No required (dB) 7.9 4.5
Uplink Eb/No required (dB) 6.1 3.1
Downlink activity factor 0.5 1
Uplink activity factor 0.5 1
Maximum mobile power (dBm) 21 24
Mobile dynamic range (dB) 65 70
Power control step size (dB) 1 1
Required Ec/Io (dB) -21 -14
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Inovação
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3G Network Planning Study with Monte-CarloSimulation
Load Impact on Coverage Probability(I)
Noise rise limit = 6 dBNoise rise limit = 6 dB
Handover margin = 6 dBHandover margin = 6 dB
BS antenna tilt = 0ºBS antenna tilt = 0º
BS antenna height = 25 mBS antenna height = 25 m
DL soft handover gain = 2DL soft handover gain = 2dBdB
Pilot power = 30Pilot power = 30 dBm dBm
BS antenna aperture = 85ºBS antenna aperture = 85º
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3G Network Planning Study with Monte-CarloSimulation
Load Impact on Coverage Probability(II)n Load impacts on the coverage area (cell
“breathing” effect).n Increasing the traffic density deteriorates
the QoS.n Cell load depends of the cell captured
traffic (uniformly distributed).n Large cells experience worse coverage
probability (they serve more traffic).
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3G Network Planning Study with Monte-CarloSimulation
Noise Rise Limit Variation (I)
Uplink transmittedpower
Handover margin = 6 dBHandover margin = 6 dB
BS antenna tilt = 0ºBS antenna tilt = 0º
BS antenna height = 25 mBS antenna height = 25 m
DL soft handover gain = 2DL soft handover gain = 2dBdB
Pilot power = 30Pilot power = 30 dBm dBm
BS antenna aperture = 85ºBS antenna aperture = 85º
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Inovação
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3G Network Planning Study with Monte-CarloSimulation
Noise Rise Limit Variation (II)
n Increasing the noise rise limit increasesthe maximum allowed interference in thecell.
n More interference allowed means morecapacity, but on the other hand it alsomeans less system stability.
n The consideration of no noise rise limitleads to the exclusion of terminals due touplink and/or downlink low level of Eb/No.
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Inovação
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3G Network Planning Study with Monte-CarloSimulation
Handover Margin Variation (I)
Soft Handover Probability Noise rise limit = 6 dBNoise rise limit = 6 dB
BS antenna tilt = 0ºBS antenna tilt = 0º
BS antenna height = 25 mBS antenna height = 25 m
DL soft handover gain = 2DL soft handover gain = 2dBdB
Pilot power = 30Pilot power = 30 dBm dBm
BS antenna aperture = 85ºBS antenna aperture = 85º
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3G Network Planning Study with Monte-CarloSimulation
Handover Margin Variation (II)
n The handover margin has a direct impacton the number of terminals in soft/softerhandover.
n Larger handover regions result in lessaverage transmission power.
n Downlink soft/softer handoverconsequences:l Increases the number of connections.l Leads to a potential increase in the
interference (depending on the radio channelstatus and diversity gain).
l Leaves less power available to other channels.
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3G Network Planning Study with Monte-CarloSimulation
BS Antenna Tilt Angle Variation (I)
Pilot Ec/Io Noise rise limit = 6 dBNoise rise limit = 6 dB
Handover margin = 6 dBHandover margin = 6 dB
BS antenna height = 25 mBS antenna height = 25 m
DL soft handover gain = 2DL soft handover gain = 2dBdB
Pilot power = 30Pilot power = 30 dBm dBm
BS antenna aperture = 85ºBS antenna aperture = 85º
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3G Network Planning Study with Monte-CarloSimulation
BS Antenna Tilt Angle Variation (II)
n The antenna tilting angle affects the signalpath loss.
n Increasing the down tilting angledecreases the interference area. It alsoleads to an average decrease on the Eclevel, resulting in an overall decrease ofEc/Io.
n The uplink transmitted power increases inaverage with the increase of the tilt angle.
n The softer handover region increases andthe soft handover region decreases.
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3G Network Planning Study with Monte-CarloSimulation
BS Antenna Height Variation (I)
Uplink transmittedpower
Noise rise limit = 6 dBNoise rise limit = 6 dB
Handover margin = 6 dBHandover margin = 6 dB
BS antenna tilt = 0ºBS antenna tilt = 0º
DL soft handover gain = 2DL soft handover gain = 2dBdB
Pilot power = 30Pilot power = 30 dBm dBm
BS antenna aperture = 85ºBS antenna aperture = 85º
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3G Network Planning Study with Monte-CarloSimulation
BS Antenna Height Variation (II)
n Similar effects as experienced for the tiltangle variations.
n The impact is more dependent on theterrain profile.
n Lower antenna heights lead to largersofter handover regions.
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3G Network Planning Study with Monte-CarloSimulation
Downlink Handover Gain Variation (I)
Downlink Eb/No failureprobability
Noise rise limit = 6 dBNoise rise limit = 6 dB
Handover margin = 6 dBHandover margin = 6 dB
BS antenna tilt = 0ºBS antenna tilt = 0º
BS antenna height = 25BS antenna height = 25mm
Pilot power = 30Pilot power = 30 dBm dBm
BS antenna aperture =BS antenna aperture =85º85º
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3G Network Planning Study with Monte-CarloSimulation
Downlink Handover Gain Variation(II)n Directly affects the downlink performance.n Higher gains allow less downlink average
transmission power, leading to moreavailable resources to other channels.
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3G Network Planning Study with Monte-CarloSimulation
Pilot Power Variation (I)
Pilot Ec/Io Noise rise limit = 6 dBNoise rise limit = 6 dB
Handover margin = 6 dBHandover margin = 6 dB
BS antenna tilt = 0ºBS antenna tilt = 0º
BS antenna height = 25 mBS antenna height = 25 m
DL soft handover gain = 2DL soft handover gain = 2dBdB
BS antenna aperture = 85ºBS antenna aperture = 85º
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3G Network Planning Study with Monte-CarloSimulation
Pilot Power Variation (II)
n The pilot power level sets cell coveragearea.
n It affects directly the Ec/Io level.n If more power is allocated to this channel
less power is available for traffic channels.n Higher pilot powers result in higher
interference levels.
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3G Network Planning Study with Monte-CarloSimulation
BS Sector Aperture Variation (I)
Softer Handover Probability Noise rise limit = 6 dBNoise rise limit = 6 dB
Handover margin = 6 dBHandover margin = 6 dB
BS antenna tilt = 0ºBS antenna tilt = 0º
BS antenna height = 25 mBS antenna height = 25 m
DL soft handover gain = 2DL soft handover gain = 2dBdB
Pilot power = 30Pilot power = 30 dBm dBm
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3G Network Planning Study with Monte-CarloSimulation
BS Sector Aperture Variation (II)
n The radiation pattern depends on theantenna type and characteristics.
n A wider sector aperture allows largersofter handover regions.
n Larger apertures increase the interferencelevel.
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3G Network Planning Study with Monte-CarloSimulation
Voice vs Video Service (I)
Uplink Transmitted Power
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3G Network Planning Study with Monte-CarloSimulation
Voice vs Video service (II)
Pilot Ec/Io
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3G Network Planning Study with Monte-CarloSimulation
Conclusions (I)
n Coverage quality depends of trafficdensity.
n Higher noise rise limit allows morecapacity but also more interference.
n Increasing the handover margin reducesthe transmission power but increasesdownlink resources utilization and theinterference.
n The antenna tilting and height define Ec/Iolevel and the interference captured.
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3G Network Planning Study with Monte-CarloSimulation
Conclusions (II)
n The cell size is defined by the pilot powerthat also causes interference.
n The downlink handover gain mirrors theadvantages of soft/softer handover.
n The antenna sector aperture sets thecaptured interference and softer handoverarea.
n For the same cell total throughput, thevideo service produces less interferencethan voice but the terminals transmittedpower is considerably higher.
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Inovação
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3G Network Planning Study with Monte-CarloSimulation
Thank you for yourattention!