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1
A Three-Step Approach toCDMA2000 Network Capacity
Enhancement
Dr. Joseph ShapiraCEO
Celletra Ltd.
Presentation atCDG Technology Forum
San Francisco, October 1, 2002
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Contents
• Capacity limits and the optimization process
• Transmit Diversity
• CellShaper
• The “Smart cluster”
• 3 steps migration
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CDMA linksare not symmetrical
Expands when loadedShrinks when loadedCell boundary
Limited dynamic rangeHigh dynamic rangePower control
BTS powerUser’s powerCoverage limit
Power. Coveragematching to up link
Interference.System instability
Capacity limit
Forward linkReverse Link
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Network Optimization/Capacity Maximization Process
Improve the channel – reducerequired Eb/Io margin
– Receive diversities– Transmit diversities
Reduce SHO overhead
– beam shape and tilt– back off pilot
Balance the loads/ manage sectorresources
– Intersector balance– Intercell balance
Smart Antenna
– Optimize the channelper user
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Transmit Diversity
Rx Diversity
MS
ΣΣΣΣ TDU
Tx Diversity
MS
Transmit Diversity in IS95, and in CDMA2000, is “blind”
There is no feedback from the MS on the optimal signals’ conditioning forcombining
Tx power is split between two spaced antennas, and “colored” soas to be differentiated and optimally combined at the MS
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Transmit Diversity Techniques cdmaOne and CDMA2000
TDTD (Time Delay TD)PSTD (Phase Sweeping TD)
STTD is the preferred diversity technique for CDMA2000The diversity gain of TDTD falls short of STTD by 1.2 to 2 dB
CDMA2000 STTD (Space-Time TD) or STSOTD (Orthogonal TD)
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Celletra TDAAdd-On Transmit Diversity
! Provides Transmit Diversity to Installed BTS – IS95 /CDMA2000
! Add-On, overnight installation and commissioning! Multicarrier! No change to the antennas
Live markets proven capacity increase of 15 to 50%(environment and traffic dependent)
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Network Optimization/Capacity Maximization Process
Improve the channel – reducerequired Eb/Io margin
– Receive diversities– Transmit diversities
Reduce SHO overhead
– beam shape and tilt– Back-off pilot
Balance the loads/ manage sectorresources
– Intersector balance– Intercell balance
Smart Antenna
– Optimize the channelper user
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CellShaper add-on•Add-on to operating BTS
•Multicarrier
•A simple upgrade from TDA
•Antennas form-fit to legacyantennas
•Full remote control on-the-fly
Features•Sector width control
•Sector orientation control
•Beam tilt
•Transmit and receive spacediversity
•Capacity improvement 30%- 100% (environment andtraffic distribution dependent)
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CellShaper comparison withMultibeam Rosette Shaper
Advantage
NoneAdvantageTilt control
Performance comparisonDensity peak <400
Wider peakInter-cell balancing
No Tx diversityAngle Rx diversity
Space Tx diversitySpace Rx diversity
Diversities
ComplexOvernightInstallation
Large footprint in cabinetSplit BTS PA, or add ½PA. One-drawer interfaceand control.
Hardware
4 column multibeamForm-fit to legacyantennas
Antennas
MB ShaperCellShaperFeature
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Smart ClusterTM
IntegratedMeasurementand Control
System(IMC)
C-S
C-S
C-S
C-S
C-S - Cell-Shaper system
NMS / DBS
Dynamically Optimized Cluster ofCellShapers
Capacity increase 60% to 150%
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The Migration Path
IntegratedMeasurementand Control
System(IMC)
BTS
Existing cell site
Step 1Add-On Transmit Diversity
TD - Transmit Diversity
Step 2Add-On Cell-Shaper
Beam Width , BeamOrientation and Tilt Control
Step 3Smart Cluster
C-S
C-S
C-S
C-S
C-S - Cell-Shaper system
NMS / DBS
BTS
BTS
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Capacity Steps
Existing Cell Site
Transmit Diversity Add-On
Add-OnCell - Shaper
Smart Cluster
Step 1 >>> Step 2 >>> Step 3
Performance Improvement Capacity or Coverage
15% - 50%+ Capacity
30% - 100%+ Capacity
60% - 150%+ Capacity
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