Course RF200
Wireless Wireless CDMA CDMA RF RF Performance Performance Optimization Optimization
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Contents Chapter 1. Introduction 2. Foundation Topics Layer-3 Messaging Call Processing Performance Indicators and Problem Signatures PN Planning and Search Windows 2. Analyzing System Performance System Data and Analysis Techniques 3. Mobile Field Tools and Data Analysis Autonomous Mobile Mobile Data Collection Collection Conventional Field Data Collection Tools 4. Multiple Carrier Systems: Operating Principles and Analysis 5. Applied Optimization 6. 1xRTT Optimization Issues Appendix I. Cell Loading Loading Example Appendix II. CDMA/3g1x CDMA/3g1x Books, Publications, Publications, Web Resources Resources August, 2007 2007
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Contents Chapter 1. Introduction 2. Foundation Topics Layer-3 Messaging Call Processing Performance Indicators and Problem Signatures PN Planning and Search Windows 2. Analyzing System Performance System Data and Analysis Techniques 3. Mobile Field Tools and Data Analysis Autonomous Mobile Mobile Data Collection Collection Conventional Field Data Collection Tools 4. Multiple Carrier Systems: Operating Principles and Analysis 5. Applied Optimization 6. 1xRTT Optimization Issues Appendix I. Cell Loading Loading Example Appendix II. CDMA/3g1x CDMA/3g1x Books, Publications, Publications, Web Resources Resources August, 2007 2007
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Course RF200
Introduction Introduction to to Performance Performance Optimization Optimization
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Welcome to Course RF200
Course RF100 is an introduction to RF and CDMA principles. After completing it, you should be familiar with: • General RF system design principles • CDMA technolo technology gy - princi principles, ples, channels channels,, network basics basics • key fundamentals of Messaging and Call Processing Course RF200 covers how to recognize and deal with system performance problems • key performance indicators and what they mean • what tools are available for discovering and analyzing problems • mechanisms and situations that cause trouble • how to solve many of the problems you’ll see
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A
Good Performance is so Simple!! BTS
BTS
BTS
o I / c E
A S T B
B S T B
FORWARD LINK
One, Two, or Three good signals in handoff • Composite Ec/Io > -10 db Enough capacity • No resource resource probl problems ems – I’ve got got what what I need
C -10 S T B available power Traffic Channels In use Paging Sync Pilot
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Good Performance is so Simple!! BTS
BTS
BTS
o I / c E
A S T B
B S T B
One, Two, or Three good signals in handoff • Composite Ec/Io > -10 db Enough capacity • No resource resource probl problems ems – I’ve got got what what I need
C -10 S T B
In principle, a COW next door can solve almost any CDMA problem!
Reality Check: FORWARD LINK
available power Traffic Channels In use Paging Sync Pilot
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1. But who has enough regular cells OR cows or money to fix every problem location?!! 2. Problems Problems occur in the areas between cells’ cells’ dominant dominant coverage. Adding a cow only pushes the problems out to its own boundary with other cells. Conclusion: We need to design better, and to use our existing cells more effectively. We need to provide one, two, or three dominant signals everywhere.
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Bad Performance Has Many Causes +41
+8
360 A
360+33c
BTS
B BTS
No Available B Power!
T S S e Traffic c t o Channels r In Use T r a n s m Paging i t Sync t e r Pilot
BTS Rx Pwr Overload
CEs
x
Vocoders Selectors
BTS A PN 100
BTS B PN 99
ACTIVE SEARCH WINDOW
1 mile
11 miles
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Weak Signal / Coverage Hole Pilot Pollution • Excessive Soft Handoff Handoff Hando ff Failu Failures, res, “Rogu “Rogue” e” mobil mobiles es • Missing Neighbors • Search Windows Too Small • BTS Resource Overload / No Resources – No Forward Power, Channel Elements – No available Walsh Walsh Codes – No space in Packet Packet Pipes Pilott “Surprise” Pilo “Surprise” ambus ambush; h; Slow Handoffs Handoffs PN Plan errors Slow Data Problems: RF or IP congestion Improper Impro per cell or reradia reradiator tor confi configurat guration ion Hardware and software failures But on analysis analysis,, all of these problem problems’ s’ bad effects happen because the simple few-signal ideal CDMA environment isn’t possible.
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What is Performance Optimization?
The words “performan “performance ce optimizatio optimization” n” mean different different things things to different people, viewed from the perspective of their own jobs System Performance Optimization includes many different smaller processes at many points during a system’s life • recognizing and resolving system-design-related issues (can’t build a crucial site, too much overlap/soft handoff, coverage holes, etc.) • “clus “cluster ter testin testing” g” and “cell “cell integr integration ation”” to ensure ensure that new base station hardware works and that call processing is normal • “fine “fine-tuni -tuning” ng” syste system m parameters parameters to wring out the best possible possible call performance • identifying causes of specific problems and customer complaints, and fixing them • carefully watching system traffic growth and the problems it causes cause s - imple implementi menting ng short-term short-term fixes to ease “hot “hot spots”, and recognizing problems before they become critical
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Performance Optimization Phases/Activities Phase
Drivers/Objectives
Activities
Main Tools
Success Indicators
RF Design and Cell Planning
Cover desired area; have capacity for anticipated traffic
Plan cells to effectively cover as needed and divide traffic load appropriately
Prop. Models, Test Transmitters, planning tools
Model results
New Cluster Testing and Cell Integration
Ensure cells properly constructed and configured to give normal performance
Drive-test: coverage, all handoff boundaries, all call events and scenarios
Drive-test tools; cell diagnostics and hardware test
All handoffs occur; all test cases verified
Solve Specific Performance Problems
Identify problems from complaints or statistics; fix them!
Detect, Investigate, Resolve performance problems
Drive-test tools, system stats, customer reports
Identified problems are resolved
Well-System Performance Management
Ensure present ‘plant’ is giving best possible performance
Watch stats: Drops, Blocks, Access Failures; identify/fix hot spots
System statistics
Acceptable levels and good trends for all indicators
Capacity Optimization
Manage congested areas for most effective performance
Watch capacity indicators; identify problem areas, tune parameters & configuration
Smart optimization of parameters; system statistics
Stats-Derived indicators; carried traffic levels
Traffic analysis and trending tools; prop. models for cell spliiting; carrier additions
Sectors are expanded soon after first signs of congestion; capital budget remains within comfortable bounds
Growth Management: Optimizing both Performance and Capital Effectiveness
hello
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Overall traffic increases and congestion; competition for capital during tight times
Predict sector and area exhaustion: plan and validate effective growth plan, avoid integration impact
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