3G1x RF Optimization Guideline

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Version 1.0 Lucent Technologies Proprietary

Do not distribute outside the company

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3G1x RF Optimization Procedures and Guidelines for PCS and CellularCDMA Systems

Version 1.0

Dec 2001

Prepared byDevesh Patel

CDMA RF Optimization and Applications Group

Lucent Technologies, Bell Laboratories

Whippany, New Jersey


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Chapter 1: RF Optimization........................................................................................................................41-1 Introduction.....................................................................................................................................41-2 A high-level view of 3G1x optimization procedures ......... ........... .......... ........... ........... .......... ........ 4

1-2.1 System Preparation Phases...................................................................................................... 51-2.1.1 Spectral Testing...............................................................................................................51-2.1.2 System Pre-Test ..............................................................................................................51-2.1.3 Sector Testing ................................................................................................................. 5

1-2.2 RF Optimization Test phases .................................................................................................. 61-2.2.1 Cluster Testing Unloaded and Loaded coverage tests.................. .......... ........... .......... . 61-2.2.2 System-wide Testing.......................................................................................................7

Chapter 2: Cold Start of a 3G1x System..................................................................................................... 82-1 Optimization objectives .................................................................................................................. 8

2-1.1 3G1x Voice only network....................................................................................................... 82-1.2 Combined 3G1x Voice/Data system....................................................................................... 9

2-2 3G1x CDMA System Parameters ................................................................................................... 92-2.1 3G1x Voice only network....................................................................................................... 9

2-2.1.1 Primary Parameters.........................................................................................................92-2.1.2 Secondary Parameters................................................................................................... 112-2.1.3 Fixed Parameters........................................................................................................... 12

2-2.2 Combined 3G1x Voice/Data network................................................................................... 132-2.2.1 Primary Parameters.......................................................................................................132-2.2.2 Secondary Parameters................................................................................................... 132-2.2.3 Fixed Parameters........................................................................................................... 14

2-3 Optimization Cluster Selection .....................................................................................................142-4 Optimization Procedures............................................................................................................... 15

2-4.1 RF Optimization for Voice only Cold Start .......................................................................... 152-4.1.1 Loading Procedures....................................................................................................... 152-4.1.2 Data Collection Tools ................................................................................................... 162-4.1.3 Data Analysis Tools......................................................................................................182-4.1.4 Personnel requirements .................................................................................................212-4.1.5 Performance Tests.........................................................................................................21

2-4.2 RF Optimization for a Combined 3G1x Voice/Data network............. ........... .......... ........... .. 33

2-4.2.1 Loading Procedures....................................................................................................... 352-4.2.2 Data Collection Tools ................................................................................................... 362-4.2.3 Data Analysis Tools......................................................................................................432-4.2.4 Personnel Requirements................................................................................................462-4.2.5 Performance Tests.........................................................................................................47

2-5 Techniques for mitigating Common RF Optimization Problems............ .......... ........... ........... ...... 572-5.1 Common set of RF optimization problems for 3G1x Voice only or combined 3G1xVoice/Data optimization .......................................................................................................................57

2-5.1.1 No Service..................................................................................................................... 572-5.1.2 Dropped Calls ............................................................................................................... 582-5.1.3 Poor Voice Quality........................................................................................................60

2-5.2 Additional RF optimization problems specific to combined 3G1x Voice/Data system........ 612-5.2.1 Poor Data Throughput/SCH Assigned Rate/SCH FER in an unloaded system ............ 61

2-6 Post commercial monitoring parameters......... .......... ........... .......... ........... .......... ........... .......... ..... 63Chapter 3: Migration Scenarios ................................................................................................................ 643-1 Introduction................................................................................................................................... 643-2 Migration Scenarios Configuration and Optimization considerations ......... ........... .......... ......... 65

3-2.1 Introducing 3G1x Voice in a 2G system on an existing carrier throughout the network ...... 653-2.1.1 Configuration ................................................................................................................ 653-2.1.2 Optimization Considerations.......... ........... .......... ........... .......... ........... .......... ........... ..... 65

3-2.2 Introducing 3G1x Voice partially in a 2G system on an existing carrier .......... .......... .......... 663-2.2.1 Configuration ................................................................................................................ 663-2.2.2 Optimization Considerations.......... ........... .......... ........... .......... ........... .......... ........... ..... 67


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3-2.3 Introducing 3G1x Voice in a 2G system on a new carrier throughout the network............. . 683-2.3.1 Configuration ................................................................................................................ 683-2.3.2 Optimization Considerations.......... ........... .......... ........... .......... ........... .......... ........... ..... 69

3-2.4 Introducing 3G1x Voice partially in a 2G system on a new carrier .......... ........... ........... ...... 703-2.4.1 Configuration ................................................................................................................ 703-2.4.2 Optimization Considerations.......... ........... .......... ........... .......... ........... .......... ........... ..... 70

3-2.5 Introducing 3G1x Voice/Data in a 2G system on an existing carrier throughout the network ............................................................................................................................................... 71

3-2.5.1 Configuration ................................................................................................................ 713-2.5.2 Optimization Considerations.......... ........... .......... ........... .......... ........... .......... ........... ..... 72

3-2.6 Introducing 3G1x Voice/Data partially in a 2G system on an existing carrier ........... .......... 733-2.6.1 Configuration ................................................................................................................ 733-2.6.2 Optimization Considerations.......... ........... .......... ........... .......... ........... .......... ........... ..... 73

3-2.7 Introducing 3G1x Voice/Data in a 2G system on a new carrier throughout the network ..... 743-2.7.1 Configuration ................................................................................................................ 743-2.7.2 Optimization Considerations.......... ........... .......... ........... .......... ........... .......... ........... ..... 74

3-2.8 Introducing 3G1x Voice/Data partially in a 2G system on a new carrier .......... ........... ........ 753-2.8.1 Configuration ................................................................................................................ 753-2.8.2 Optimization Considerations.......... ........... .......... ........... .......... ........... .......... ........... ..... 76

3-2.9 Introducing 3G1x Data in a 3G1x Voice only system ........... .......... ........... ........... .......... ..... 763-2.9.1 Configuration ................................................................................................................ 763-2.9.2 Optimization considerations............... .......... ........... .......... ........... .......... ........... .......... .. 77

Chapter 4: Special Topics .......................................................................................................................... 794-1 3G1x to 2G handoffs..................................................................................................................... 79

4-1.1 3G1x to 2G same frequency handoffs (Voice calls only) .......... ........... .......... ........... .......... . 794-1.2 3G1x to 2G inter-frequency handoffs (Voice calls only).......... ........... .......... ........... .......... .. 80

4-2 3G1x to 3G1x inter-frequency handoffs ....................................................................................... 824-3 RF load balance across carriers and across technologies ........... .......... ........... .......... ........... ......... 82

4-3.1 Idle mode hashing ................................................................................................................. 824-3.2 Allow 3G1x Carrier sharing..................................................................................................824-3.3 Traffic channel mode load management ......... ........... .......... ........... .......... ........... ........... ...... 82

4-3.3.1 RF Loading Option ....................................................................................................... 824-3.3.2 CCC option ................................................................................................................... 84

4-3.3.3 Origination carrier option..............................................................................................84Chapter 5: Acknowledgements..................................................................................................................85Chapter 6: References ................................................................................................................................ 85


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Chapter 1: RF Optimization

1-1 IntroductionThis document presents set of procedures and guidelines for optimizing a 3G1x network. The term RF

optimization used in this document refers to a drive test measurement based process utilized to tune allaspects of over-the-air performance of a system. In the past, it has played an integral role in preparing asecond generation (2G) CDMA system for commercial operation. Often, it has also served as a continualprocess extending beyond the first commercial cut-over, such as, fine-tuning performance, when newcells/carriers are added to a network, or as traffic volume/pattern changes with increasing subscriber base.

Voice service has been the primary emphasis for the 2G CDMA deployments. The third generation (3G1x)CDMA systems cater to both Voice and Data1 needs.

This document presents a set of guidelines and procedures to perform RF optimization for a 3G1x CDMAsystem. Different markets may present different deployment configurations to optimize. Some specialconsiderations may be required for each. Towards that end, this document first discusses the procedures fora Cold Start of a 3G1x system. These are addressed in Chapter 2. A Cold Start system is further classified

into 3G1x Voice only or combined 3G1x Voice/Data system.

Any potential migration scenarios such as 2G to 3G1x Voice only, or 2G to 3G1x Voice/Data, or 3G1xVoice only to 3G1x Data are covered next in Chapter 3, with discussions on specific optimization needs.

Chapter 4 covers some special topics such as discussion on inter-frequency/inter-technology handoffs andcarrier/technology load balancing.

Note that the optimization procedures for a 3G1x Voice only network are consistent with those for a 2Gsystem (Voice and/or circuit switch low-speed Data). There are some minor changes such as using a 3G1xphone instead of 2G for data collection, using updated version of CAIT software for data collection, usingLDAT3G instead of LDAT for analysis; but the various test phases, data analysis and troubleshootingmethods remain the same. Optimizing for Data poses some additional requirements on the procedures. Itimpacts data collection toolkits, data collection and analysis process, and troubleshooting.

It is also worthwhile to point out that this document assumes any new service is introduced on a singlecarrier. It does not discuss scenarios where multiple carriers are introduced. Second, it does not addressoptimization methods for inter-frequency handoffs where required as in the case of certain 2G to 3G1xmigration scenarios. It simply refers to [1], a document available on RFEC web site(http://rfec.wh.lucent.com) that contains detailed information on design and optimization of a pure 2Gmulti-carrier system.

Note that the 2G inter-frequency handoff methods and optimization techniques also apply in case of a pure3G1x multi-carrier system, or for a mixed 2G/3G1x system where 3G1x to 2G inter-frequency handoffborders are formed. Therefore, the reader is encouraged to familiarize with [1] in order to develop a morecomprehensive understanding of all types of optimization methods. This document, however, discussesoptimization techniques for newly developed 3G1x to 2G same-carrier handoffs as they set in some

differences compared to the existing handoff techniques.

1-2 A high-level view of 3G1x optimization proceduresBelow we outline the optimization procedures needed for a 3G1x system. Since there are many commonelements between optimizing a 3G1x Voice only or a combined 3G1x Voice/Data network, we mainlypresent a common view, but highlight any considerations when optimizing for Data.

1 The term Data or 3G1x Data in this document refers to the High-speed packet-data capability of3G1x. This is primarily achieved via the use of Fundamental and Supplemental channels on either link.


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The CDMA RF optimization procedures defined here cover any IS2000 based terrestrial system 800 MHzcellular, 1.9GHz PCS or any other spectrum as in case of international deployments. Because of thepredominance of Radio Configuration 3 (RC3) based systems likely to be deployed, the procedures aremainly written for a RC3 configuration. However, only minor changes to the procedures are required toaccommodate other radio configurations.

Before proceeding to the actual optimization testing, it is necessary to prepare the system for optimization.The preparation phases include Spectral clearance testing, System Pre-Test and Sector testing. These arevery similar to those for 2G optimization, as discussed below.

1-2.1 System Preparation PhasesSpectral clearance testing can be performed as early as during the RF planning stages. The cells do not evenhave to be installed. The rest of the preparation phases can only begin after installing the cells. Since cellswill be installed and integrated gradually not all cells will be ready at the same time this should be suchthat at the conclusion of the preparation phases, optimization testing can be performed. The latter consistsof cluster tests, so it is desirable to install cells in geographical contiguous areas.

1-2.1.1 Spectral Testing

The Spectral clearance tests entail ensuring a clear spectrum with sufficient guard band and guard zone. Ifstrong in-band interference is present, even intermittently, then radio performance can be significantlydegraded for the CDMA system. In extreme cases, it can be a time consuming, difficult task to identify andmitigate the sources of external interference (e.g. microwave data transmissions, externally generatedintermodulation products, wideband noise from arc welders and other machinery, etc.); therefore, it isimportant to ensure clear spectrum as early as possible. These spectral monitoring tests also provide abaseline dataset of measured background interference levels that can be used to optimize reverse overloadcontrol thresholds and jammer detection algorithms for given environmental conditions.

1-2.1.2 System Pre-Test

Following the Spectral clearance tests, System Pre-Test is initiated. This mainly includes troubleshootingand verifying cell hardware operation and configuration, translation scrub and preparing initial neighborlists. RF Antennas are swept to detect any cabling/connection issues by measuring reflection losses. Cableand insertion losses are catalogued. Antenna downtilts are verified. Next any alarms suggesting bad cell

hardware such as LAC, GPS, Packet Pipe trouble notifications are investigated and cleared. Any island cellissues are investigated. A thorough translation scrub is performed to set them per recommendations. Therecommendations for RF parameters can be found from RF Translation Application Notes. Finally, a firstcut of neighbor lists are programmed in the FCI forms (for softer/er handoffs) as well as CDHNL forms(for multi-carrier handoffs). General guidelines are maintained to keep neighbor lists small and maintainneighbor list integrity. A typical initial neighbor list for a sector includes cross-face sectors of the same cellas well as any inward facing sectors of the first tier neighboring cells. Bi-directional neighbor lists are alsoensured.

1-2.1.3 Sector Testing

Following the System Pre-test, the first step of the Sector test is to exercise basic call processing functions,including origination, termination and handoff, to assure that these rudimentary telephony capabilities areoperational. Quick measurements are then made of CDMA signal levels, either over-the-air or with a power

meter, to verify that each cell site is transmitting the appropriate power levels. These basic functional testsare intended to detect hardware, software, configuration, and translation errors for each cell site in thecluster prior to drive testing. In case of optimizing for a Voice/Data network, the tests will expand toensure a high-speed Data call can be made. Under no load, system should be able to support highestconfigured rate (such as, 16x, i.e., 153.6 kbps)2 close to a sector, assuming there is minimal othersector/cell interference. This verifies proper translation parameter configuration and backhaul provisioning.Following Sector testing, the cells are ready for RF optimization.

2 Note that some commercial mobiles may only be able to support a maximum rate of 8x (i.e., 76.8 kbps)on the reverse supplemental channel.


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1-2.2 RF Optimization Test phasesAs proposed, the optimization procedures whether for a 3G1x Voice only network, or a combined 3G1x

Voice/Data, are to be conducted in two phases: cluster testing and complete system-wide optimization. The

phases are similar to those for 2G optimization, especially for 3G1x Voice, where as 3G1x Data requires

additional data collection equipment and fine-tuning. The initial pass of the RF optimization will be

performed as a part of the cluster tests; the second, more detailed tuning phase, will occur after completionof all cluster tests, once all cell sites in the CDMA network are activated. The primary reason for breaking

the optimization work into two phases is to reduce the time and resources required for completing the

cluster test cycles.

For 3G1x Data, there is an additional requirement to ensure RF coverage to achieve good Data performance

in terms of assigned rate, SCH FER as well as throughputs in as large an area of a network as possible.

During the RF optimization process, CDMA parameters will be adjusted using simulated traffic loading,

due to the extreme cost and logistical obstacles associated with employing live traffic. In all cases, forward

link loading will be implemented using Orthogonal Channel Noise Simulator (OCNS). Reverse link

loading will be achieved through the use of an attenuator and circulator at the mobile.

1-2.2.1 Cluster Testing Unloaded and Loaded coverage testsCluster testing consists of a series of procedures to be performed on geographical groupings of cells. The

number of cells in each cluster is relatively large to characterize the effect of a parameter change. Secondly,

it provides enough forward link interference to generate realistic handoff boundaries in the vicinity of the

center cell and the first ring of cells. A cluster of fewer cells would provide acceptable results over too

small of a geographic area. Approximately one tier of cell overlap is provided between each cluster and the

next to afford continuity across the boundaries. The goal is to complete all tests for a given cell cluster,

while minimizing the utilization of test equipment, personnel, and time. For this reason, cluster testing is

intended to coarsely tune basic CDMA parameters and to identify, categorize, and catalog coverage

problem areas. No attempt will be made to resolve complicated coverage problems during the cluster test

phase; such location-specific, detailed refinements will be deferred until the system-wide optimization

phase.

After basic cell operation has been verified, surveys of forward link pilot channel coverage are performedwith light traffic load on the system. During the unloaded survey measurements, all cells in the cluster are

simultaneously transmitting forward link overhead channels (i.e. Pilot, Sync, QPCH and Paging), with a

minimal number of Fundamental traffic channels active (typically 0 to 2). In case of Data, in addition to the

Fundamental traffic channels, there may not be more than one high-speed Supplemental channel (max rate

of 16x) on each link. The drive routes used in the measurements are to be jointly selected by Lucent and the

wireless service provider. In general, the drive routes will include, at a minimum, major freeways and

roadways where high levels of wireless traffic are to be expected. Drive routes may also be selected to

explore weak coverage areas and regions with multiple serving cells, as predicted by propagation modeling

software (e.g. CE4), or based on knowledge of the surrounding terrain topography.

The unloaded pilot survey results identify coverage holes, handoff regions, multiple pilot and non-dominant

coverage areas. The pilot survey information highlights fundamental flaws in the RF design of the cluster

under best-case, lightly loaded conditions. The pilot survey provides coverage maps for each sector in thecluster; these coverage maps are used during the optimization phase to adjust transmit powers and neighbor

lists. Finally, measuring the pilot levels without load serves as a baseline for comparison with

measurements from subsequent cluster tests under loaded conditions. Characteristics of cell shrinkage can

be compared under the extremes of light and heavy traffic load.

The final measurements to be performed as a part of the cluster testing are coverage drive runs conducted

under loaded conditions. Drive routes for the loaded coverage testing will be exactly the same routes as

those used for the unloaded coverage surveys. The objectives are to provide coarse system tuning and to

identify, categorize, and catalog coverage deficiencies so the more difficult problems can be resolved


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during later optimization tests. Simulated traffic loading will be accomplished primarily using OCNS and

mobile attenuators. Although the loading mechanisms will be the same, there will likely be difference in

levels of loading utilized when optimizing a Voice only system versus a combined Voice/Data system.

1-2.2.2 System-wide Testing

After all clusters in the CDMA network have been tested, system-wide optimization will begin with all

cells activated. Optimization teams will drive test each of the problem areas identified during the clustertesting, using the same test conditions under which the problem was previously observed. Iterative tuning

procedures will be used to fix coverage problems by adjusting transmit powers, antenna configurations and

neighbor list entries and Neighbor Set search windows. In extreme situations, handoff thresholds, Active

Set search window sizes, cell search window size, or other low-level tuning parameters may have to be

modified. If the field team cannot resolve coverage problems in one hour, then the team will flag the

problem area for further investigation by other RF support personnel.

After attempts have been made by the site team to resolve the individual coverage problem areas, the

system-wide optimization will proceed to the final phase. The final optimization step will be a

comprehensive drive test covering the major highways and primary roads in the defined coverage area for

the CDMA network. During the system-wide drive run, simulated loading will be used to model traffic on

the network. Performance data will be collected as a small number of active CDMA subscriber unit traverse

the system-wide drive route. Statistics will be collected to characterize pilot, paging, traffic, and accesschannel coverage over the entire drive route. Specific problem areas identified by the system-wide drive

run will be addressed on a case-by-case basis, after the entire drive has been completed. Comprehensive

statistics from the system-wide drive will be used to assess the overall performance quality of the network,

including dropped call rates, handoff probabilities, frame erasure statistics. When optimizing for Data,

additional metrics will include throughputs at the RLP and physical layers.

Following the system wide optimization test, dropped call, origination and termination tests are executed to

sample the dropped call and access performance in the network. Note that these are typically optional tests,

performed only if specified in the contract. For 3G1x Voice only optimization, additional physical layer

parameters can also be measured to preview potential performance during the Acceptance criteria testing.

In addition when optimizing for 3G1x Data, metrics, especially, RLP and physical layer throughputs can

also be measured via the Data call. A concurrent 3G1x Voice phone can provide the dropped call and

access performance statistics.

At the conclusion of the above tests, the RF optimization procedure will be considered complete and the

CDMA network ready for live traffic testing and market trials leading into commercial service. Once

significant loading with live traffic is present on the CDMA network, additional tuning of the system

parameters will be required to accommodate uneven traffic conditions (e.g. traffic hot spots, unusual traffic

patterns, etc.) and other dynamic effects which cannot be easily predicted or modeled with simulated traffic

loading.


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Chapter 2: Cold Start of a 3G1x System

Cold start refers to a brand new deployment. Cold start could be for various scenarios such as 3G1x Voice

only, 3G1x Data only or combined 3G1x Voice/Data system. To simplify and address most common

configurations, this document focuses mainly the 3G1x Voice only and combined 3G1x Voice/Data

systems.

Cold start of a 3G1x Voice only system is straightforward configuration much like a brand new 2G

network. The similarities in basic configuration and performance metrics between 2G and 3G1x Voice call

also lead to very similar optimization methods and procedures.

Since Data is likely to co-exist with Voice in most networks where maintaining quality of service for Voice

will be critical, we consider Cold Start of a combined Voice/Data system rather than a Data only system.

This is particularly important since at this point, Voice and Data services can not be fully separated across

carriers, therefore, for combined systems, it will mean both services will co-exist on the same carrier.

This chapter first introduces optimization objectives for the two Cold Start configurations. In section 2-1, it

provides an overview of optimization procedures where many similarities exist between the two

configurations. Any differences are highlighted. Next in section 2-2, it specifies several CDMA parameterscategorizing them per their use during RF optimization. Section 2-3 presents considerations for selecting

optimization cluster. These are the same regardless of the configuration.

Next, section 2-4 presents actual set of optimization procedures for each configuration. There is a detailed

discussion on optimization tests, loading methods, data collection and analysis tools, performance tests,

data collection procedures and data analysis methods. In section 2-5, typical set of optimization problems

as well as potential remedies are outlined.

Finally, there is a discussion on fine-tuning performance during commercial operation. Several system level

metrics are identified such as dropped call, access failures, FER rate, Erlang usage, etc. It also provides

some information on balancing RF load as well as achieving some Voice/Data separation across carriers.

These will likely be adjusted based on customer expectations and as subscriber usage grows.

2-1 Optimization objectivesBefore discussing the procedures, it is important to understand the objectives behind optimizing a 3G1x

system. These are listed below for each of the two main configurations.

2-1.1 3G1x Voice only networkThe optimization objectives for a 3G1x Voice only network are similar to that of a 2G system. The most

significant objectives are as follows.

- Ensure that acceptable coverage is achieved for the pilot, paging, quick paging, synchronization,

access, and traffic channels. These objectives are measured based on metrics such as FER, Pilot Ec/Io,

mobile transmit power and mobile receive power. Ensuring good coverage helps minimizing dropped

calls.

- Minimize the number of dropped calls, missed pages, and failed access attempts. The performance is

measured from dropped call and origination/termination attempts.

- Control the overall percentages of 1, 2, and 3-way soft/softer handoff. The performance is measuredvia overall handoff statistics with and without loading. Usually the soft/softer handoff thresholds are

sparingly adjusted. Attempt is to maintain consistent thresholds across the network. Note that CDMA

release 17.1 introduces IS95B SHO algorithm. IS95B algorithm if enabled also applies to 3G calls.

Further study is needed to understand the performance impact as well as recommend values for the

associated thresholds. Until such time, it is recommended to continue to utilize the existing IS95A

algorithm.

- Provide reliable intra-technology (2G to 2G, or 3G to 3G) and inter-technology (3G to 2G) handoffs.

The performance is measured from dropped call tests in the handoff region.


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2-1.2 Combined 3G1x Voice/Data systemAll the objectives described for 3G1x Voice only optimization also apply to 3G1x Voice/Data optimization.

In addition, it is important to ensure acceptable assigned Supplemental (SCH) rates as well as SCH FER on

both the links in as larger an area of the network as the cell design permits. This in turn helps ensure

acceptable Data throughputs for a given Data application.

On the forward link, leg carrying the SCH of a Data call is called an anchor leg. Per the current Lucentimplementation, there is only one leg transmitting SCH at any time for a Data call even if the fundamental

channel (FCH) is in soft/softer handoff. Whenever another Pilot in the FCH Active Set becomes stronger

relative to the current anchor by a certain threshold, SCH transmission is stopped and a new anchor is

established on the stronger Pilot before resuming SCH. This process is called an anchor transfer.

In order to achieve good throughputs on the forward link, it is desirable to minimize interference to the

anchor Pilot from other FCH Active Set Pilots as well as minimize the SCH interruptions stemming from

frequent anchor transfers. To meet these objectives require a conscious effort to create dominant Pilot

regions. While doing so, careful emphasis is needed to ensure basic call integrity such as soft handoff, FER

and dropped call performance for a Voice call, especially, under loaded conditions. This is because

optimization to achieve dominant coverage regions should be performed based on unloaded system

conditions when most number of Pilots are detected. With loading, cell coverage shrinks and may expose

weak coverage areas if sufficient overlap is not maintained.

2-2 3G1x CDMA System ParametersRF optimization requires adjusting several parameters that influence the performance of a network. There

are a vast number of parameters available for optimizing a CDMA system. Most of these parameters are

controlled via translations.

Some of the parameters have complex interactions with one another affecting system attributes such as

coverage, capacity and call quality. Therefore, it is important to prioritize the parameters depending on

their ability to improve performance with minimal complexity and trade-offs. The other factor to consider

when prioritizing the parameters is the frequency of usage. This is closely tied to the scope of performance

impact. Some parameters require frequent tuning depending on the local RF environment, and may also

considerably vary in their final values across the system. Certain parameters need very sparing adjustments

to influence performance on a system wide basis.

Below we classify the RF optimization parameters depending on the frequency/scope of their usage as well

as interaction complexity they generate. The three classes are Primary, Secondary and Fixed parameters.

We present these parameters first assuming optimization is performed for a 3G1x Voice only and then for a

combined Voice/Data system. As it will be evident, the latter adds only a small number of new parameters

to the list of Primary and Secondary Parameters.

2-2.1 3G1x Voice only network

2-2.1.1 Primary Parameters

These parameters require frequent adjustments, often from one cell site to another. They are the primary

knobs to control the network performance. These include:- BCR/CBR attenuation (affects total Forward Link power [3])

- Antenna adjustments (azimuth orientation, antenna height, downtilt angle, antenna type)

- Neighbor List Entries and associated Priorities [5] includes both FCI and CDHNL forms

- Hard Handoff and Semi-soft handoff Thresholds [5]

The Primary optimization parameters are the primary translations to be used to fix coverage deficiencies.

Cell site transmit powers can be adjusted with BCR/CBR attenuation to address coverage spillover,

overshoot problems, and multiple pilot coverage regions. In some cases, transmit powers can be adjusted to

provide fill-in coverage for weak signal strength areas. Additional alternatives, such as changing antenna


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downtilt or antenna pattern, can mitigate problem areas where transmit power adjustments are insufficient

to resolve a deficiency. During adjustment of BCR/CBR attenuation, care must be taken to ensure that the

forward and reverse links are approximately in balance (i.e. the tolerable path loss link margin is the same

for uplink and downlink). Adjusting coverage via Antenna adjustments tends to better preserve the link

balance once established via BCR/CBR adjustments.

Note that when adjusting the BCR/CBR values, it is important to also size the max_power translation to

maintain uniform Pilot fraction at Full load across all cells. Refer to [3] App Note for a detailed discussion

on this subject. Also note that BCR/CBR as well as max_power are per sector per carrier translation

parameters. In general, these values should be set the same across all carriers of a given sector unless in the

inter-frequency border zone where the last or the second-last tier of outward facing sectors may require

more attenuation on the discontinuing carrier.

The optimization of neighbor lists may be less of a problem during cluster tests, where typically only a

small number of cells are active, than with system-wide tests, where many more sectors are simultaneously

active. Note that there are two types of neighbor lists one are provisioned on the FCI form, other on theCDHNL form on the inter-frequency handoff border sectors configured for Directed Handoffs.

Due to the limited neighbor list size for each sector, tradeoffs are required to select entries, which minimizedropped calls because of missed handoffs or handoff sequencing problems.

For the FCI neighbor lists, specifying proper priorities is also an essential step when optimizing neighborlists. While different mobile manufacturers may implement priority based Pilot searching differently,simple rules can be followed. As a rule of thumb, the adjacent sectors of the same cell as well as facingsectors from the first tier of immediate neighbors can be afforded highest priority. Second priorityneighbors may include the sectors of the first tier cells facing away from, as well as the sectors of thesecond tier cells facing towards, the sponsoring sector. Remaining sectors in the neighbor list can be giventhe lowest priority. The above rules can be deviated selectively depending on the coverage of a particularneighbor.

For the CDHNL neighbor lists formation, refer to the guidelines presented in [1] for multicarrieroptimization.

The Neighbor Set Search window size, utilized on the forward link, should be set initially based onexpected cell sizes and multipath propagation delay spreads, as discussed in [5]. If the CDMA deploymentcontains a mixture of small cells and large cells, then window sizes may have to be adjusted on a case-by-case basis to accommodate all handoff scenarios. For example, if there is a large variation in the antennaheights for CDMA cells in the network, situations may occur where the mobile enters soft handoff with adistant cell. If the mobile uses the distant base station to obtain a timing reference, then the mobilesreference clock will be retarded by the large propagation delay between the mobile and the distant cell site.When scanning for neighbor list pilots, the mobile will center its search window around the expected timedelay of the neighbors pilot PN offset, as calculated based on the mobiles reference timing. Since themobiles reference time is retarded by the propagation delay from the distant cell to the mobile, the locationof the search window will be skewed by the propagation delay time. In such a situation, if the neighborsearch window size is not large enough, the mobile may fail to detect pilots from close-in neighbors due tothe retarded timing reference. This could result in dropped call on account of strong interference to the

mobile Active Set.

The Hard-handoff and semi-soft handoff thresholds apply to handoffs in the same frequency or inter-frequency border regions. Refer to App Notes [5] for a discussion on different types of handoff techniquesand their configuration, and to [1] for a discussion on optimizing these thresholds.


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2-2.1.2 Secondary Parameters

While most of the RF optimization is performed using the Primary parameters, the secondary parameters

can be used for further fine-tuning, especially in specific problem areas. The parameters include:

- Soft handoff thresholds including IS95B soft-handoff thresholds

- Active Set Search Window and Cell Site Search Window Sizes

- Access probe nom and initpower levels

- Sector size and Access preamble size- Pilot, Page, Sync and Quick Paging channel levels

- Forward link Traffic channel power settings

- RF Load Weighting Factor

The secondary optimization parameters can have system-wide performance impacts, and therefore should

be adjusted with caution, in cases where the adjusted parameters do not fully resolve a problem. For

example, even small changes in soft handoff thresholds can impact overall system capacity and channel

element utilization. In general, attempts should be made to keep a single set of handoff thresholds for the

entire CDMA network. For a call in handoff, the effective thresholds are not always predictable if the

handoff legs are configured with different parameter settings. For example, highest Tadd value is chosen

from among the legs. As long as the call is in handoff with the leg sponsoring the highest Tadd value, this

value will be used. This may be necessary to improve performance in a specific problem area, but could

hurt performance on a route, where, for instance, a fast rising neighbor needs to be added quickly tominimize the interference. For this reason, it is not advisable or practical to alter soft handoff thresholds on

a sector-by-sector basis.

The Active Set search window size parameter on the forward link and the cell site search window size

parameter on the reverse link parameter will generally be sized equal [5]. In general, they will be sized

based on the multipath environment. However, exceptions may be necessary, especially in an area with a

mixture of small and large cells. When the mobile is driving among cells with different radii, it constantly

slews its reference to tune to the earliest arriving cell. This creates an ambiguity for a newly added soft

handoff leg in estimating the center position of the search window. The problem becomes more apparent in

case of a hard handoff where an inadequately small search window could result in a dropped call. This is

because the mobile has already broken RF connection with the old cell site while the target cell is

attempting to acquire the mobile. In case of soft-handoff adds, the older legs can still carry the call making

the problem less obvious. Increasing the cell site search window can alleviate the problem. Following the

general guideline of keeping consistent Active Set and Cell site search window sizes, both should be

adjusted although the problem is more of a reverse link phenomenon.

The initand nom access probe level parameters are adjusted only in areas where it regularly takes more

than one probe to complete an access attempt. While poor RF coverage conditions may lead to this

condition, this could also happen in areas of excessive interference in the forward link. Higher received

power in the forward link reduces the open loop turnaround used by the mobile to transmit on the reverse

link. This often results in an inadequate probe level to close the reverse link at the first attempt. It may take

several access probe attempts at increasingly higher power before cell site hears the mobile. These probe

repetitions cause undesirable interference to the reverse link of other users. A higher nom or initsetting

provides a boost for the first access attempt to improve its likelihood of getting through to the cell site. Care

must be taken to increase these parameters only where required, as the increased power level is also a

source of interference to other users.

The Sector Size parameter applies to the reverse link and is set initially based on the designed extent of the

cell coverage. The cell site uses this to size its access channel window when searching for access probes

from the mobile. Some difficult terrains may cause the signal to be heard from larger than the designed

range. In order to maintain reliable access channel performance, the Sector Size parameter will have to be

increased accordingly.

The Sector Size also has impact on the Access Preamble Size parameter. Mobile sends an access preamble

at the beginning of a probe to assist cell site with the detection. Preamble is a series of symbols known a-


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priori to the receiver. If the Sector Size is large, it will take the cell site longer to finish searching all the

delay hypotheses tests within the access search window. Mobile must continue to send preamble until the

search is complete. Therefore, increasing Sector Size may require increasing the Access preamble size.

Refer to the App Note [6] for proportional relationship between the two parameters.

The power for overhead channels (Pilot, Paging, Sync and Quick Paging) expressed in terms of Digital

Gain Units (DGUs) is usually set uniformly across the system. In general it is recommended not altering

them due to their impact on traffic carrying capacity of the network. In some specific areas of concerns,

these may be adjusted, for example, for improving coverage at the sacrifice of capacity. Larger overhead

channel power levels may help mobile overcome any forward link coverage limitations. Another example

is to elevate Quick Paging and Paging channel power levels to improve termination success rate. Again this

will come at the expense of the traffic channel capacity of the network and/or of the quality of service of

the individual traffic channels due to increased overall interference.

Similar to the overhead channel settings, the traffic channel power levels expressed relative to the Pilot

power levels are typically set uniformly across the system. In specific cases, some deviations are possible.

For example, max_gain, the upper constraint on the cell site traffic channel power for a given user can be

increased to overcome forward link coverage limitation, especially, for cells at the edge of the system or in

low traffic regions. The parameter may also be adjusted differently for different handoff states depending

to fit specific needs. Init_gain, the power level at which a 3G1x Voice call enters traffic state, can be

adjusted higher to potentially improve call set-up failures. In stationary environments, min_gain, the lowerconstraint on the cell site traffic channel power can be adjusted to achieve desired frame error rate

distribution. These parameters have impact on traffic capacity of the network, so careful contemplation is

necessary to consider the trade-offs.

The RF loading weight factor is typically not optimized during the drive test optimization process of a new

network. This parameter can be adjusted during commercial operation to balance the objectives of

achieving desired load balance across carriers as well as reliable origination/termination performance. This

is described in more detail in section 4-3.3.1 as well as App Note [6].

2-2.1.3 Fixed Parameters

The fixed parameters involve quantities that should not be adjusted during field optimization. Changing

these parameters can create complex interactions among key system performance attributes such as

coverage, capacity, voice quality, data throughput, etc. The impact is not easy to characterize or predict,

and can vary widely from market to market, or within a market. These parameters should be adjusted only

after consulting the subject matter experts. The parameters include:

- Forward and Reverse link power control parameters

- Forward and Reverse link overload control parameters

- Remaining set search window parameters

- Reverse Pilot to FCH offset

These include forward and reverse link power control Eb/No set points, power control step size, FER

targets and overload control thresholds, and some search window sizes. Since power control plays such a

critical role in both reverse link and forward link performance for the CDMA system, related thresholds

and step sizes should only be adjusted based on simulations or lab measurements. For the optimization

tests it is recommended that reverse overload control thresholds be set to their maximum values allowed in

the translations to avoid false alarms during the loaded drive testing.

Due to the forward overload control algorithms role as the sole overdrive protection mechanism for thelinear power amplifier, the forward overload control parameters should be adjusted based on lab tests andcomputer simulations.

The Remaining Set search window parameter can be set to at least as big as the Neighbor Set searchwindow size during optimization itself. This could facilitate detection of any incomplete Neighbor Lists.


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However, once the optimization is complete, it should be set to 0, unless further fine-tuning is performed

during the commercial phase via the Undeclared Neighbor List feature.

3G1x introduces a Pilot channel on the reverse link. Each mobile transmits it while in a call. The purpose is

to assist with coherent demodulation of the reverse FCH at the cell site, to carry Forward link power control

up/down commands sent by the mobile as well as to allow better tracking of the reverse Eb/No at the cell

site. Similar to the reverse FCH, the Pilot channel itself is also power controlled by the cell site. The ratio

of Pilot to FCH, however, remains constant and can be adjusted by a translation. This ratio is called reverse

Pilot fraction. An optimum value for the parameter balances the need to achieve acceptable traffic channel

quality and overall capacity on the reverse link. Since the parameter impact needs to be evaluated on a

larger number of real users, it should not be adjusted during RF optimization where typically there one or

two fundamental channel users active.

Refer to the RF Translation Application Notes to obtain recommended values for the various Fixed

Parameters.

2-2.2 Combined 3G1x Voice/Data network

2-2.2.1 Primary Parameters

There are no additional Primary parameters compared to a 3G1x Voice only system. However, optimizing

for 3G1x Data requires a more conscious emphasis on creating dominant Pilot regions. This will be

attempted using antenna adjustments as well as CBR/BCR adjustments.

Once the coverage is adjusted, it may require further fine-tuning of neighbor lists and/or Neighbor Search

Window size parameters.

2-2.2.2 Secondary Parameters

In addition to the Secondary Parameters for 3G1x Voice optimization, additional parameters include

- Anchor hysterisis threshold

- Load preference delta for Data

As explained earlier, Anchor is the member of the FCH Active set that carries SCH transmission for a high-

speed Data call. An anchor is chosen based on the Pilot strength reporting by the mobile. Cell siteperiodically assesses the Pilot strengths to assist with burst rate allocation in the forward link as well as

need to change an anchor. When another FCH Active Set member becomes stronger than the current

anchor by a given margin, the SCH transmission is transferred to the stronger leg. This process is called

Anchor transfer. The margin is called Anchor hysterisis threshold.

The actual Anchor transfer process involves sending a message to the mobile to stop processing the current

SCH burst (via Extended Supplemental Channel Assignment Message), stopping the SCH transmission,

establishing a new anchor, sending another message to mobile to resume SCH processing at a fixed time in

the near future (via another Extended Supplemental Channel Assignment Message specifying new PN

offset, burst rate and duration), and finally resuming the transmission on the new anchor at the given time.

More the number of anchor transfers, larger the number of interruptions in Data transfer.

The anchor hysterisis threshold can be adjusted to minimize anchor transfers in areas suffering from excess

ping-ponging of Pilot strengths. While it is desirable to minimize this thrashing by adjusting coverage first

(creating dominant Pilot regions), some locations may pose tough RF environment difficult to optimize.

Larger value of the threshold can be chosen only after exhausting coverage improvement alternatives. The

trade-off is that current anchor will face stronger interference for potentially much larger amount of time

due to delayed Anchor transfer. Therefore, it needs a careful evaluation of overall performance impact in

the nearby region before making any changes.

Load preference delta for Data is a per-sector-per-alternate-carrier parameter applied at the time of

assigning an initial FCH channel for a Data call. A non-zero value for one or more carriers allows biasing


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Data calls to these carriers. This may be desirable from a customer perspective to try to minimize Voice

and Data interaction on a given carrier. Note, however, that currently there is no way to preclude Voice call

assignments to this carrier, so strict separation is not possible. Similar to the RF Loading Weight Factor,

this parameter is not optimized prior to commercial operation. Section 4-3.3.1 provides more detail on

possible fine-tuning during commercial mode.

2-2.2.3 Fixed Parameters3G1x Data introduces several new RF translation parameters. Most of them fall into the Fixed Parameters

category. These include:

- Forward and reverse power control parameters for Data FCH

- Forward and reverse power control parameters for Data SCH

- Anchor monitoring interval

- Forward and Reverse link Supplemental allocation parameters

For the FCH, there are separate set of power control parameters between Voice and Data. There are also a

new set of parameters for SCH power control such as forward and reverse Eb/No set points, step size, and

SCH gain constraints, rate offsets that also help make SCH burst rate, duration and power allocation

decisions. These should be adjusted only based on simulations, lab testing or extensive performance

validation in field. They are not changed during RF optimization. This in fact applies to all parameters

listed above.

Anchor monitoring interval sets the frequency at which cell site evaluates Forward link Pilot Ec/Io levels

for making anchor transfer decisions.

There are certain supplemental channel allocation parameters on either link designed to optimize resource

allocation, capacity and performance when assigning SCH rates to a Data user. The recommended values

are chosen after careful lab testing, simulations and performance testing in field. These also have complex

interactions with power control and capacity and hence are not adjusted during RF optimization.

Refer to RF Translation Application Notes for recommended settings of various Fixed parameters for high-

speed Data.

2-3 Optimization Cluster Selection

The cluster selection methodology remains the same as 2G when optimizing a 3G1x Voice network or acombined 3G1x Voice/Data network.

Several factors make it worthwhile to optimize the system in manageable sized clusters. First, it leads to a

better focus on the area being optimized. The lesser the number of sectors, the easier it is to track the

parameter changes and their performance impact. Second, it allows for multiple teams to optimize different

clusters simultaneously. Each team is able to maintain focus on its cluster with minimal impact from other

teams. Third, it could also help prepare the system for commercial operation quicker. Optimization in

equipped clusters can go on at the same time as the cell site equipment in other clusters is being installed.

A cluster consisting of 12-20 cells is a reasonable size to select. It allows a more complete characterization

of a parameter change as the impact generally carries over to one or two surrounding tier of cells. Having a

cluster consisting of roughly two tier of cells will also generate sufficient forward link interference for

proper evaluation of performance at the center cell and the first tier.

It is important to have some overlap of cells between a pair of adjacent clusters. It will simplify the system

wide optimization performed after the individual clusters are optimized. It may be worthwhile to utilize

natural barriers such as hills, water bodies, etc. for cluster separation to minimize the need for overlap.

Once the clusters are finalized, each optimization team will be assigned a cluster. The team will carry out

optimization per the procedures listed in the following section.


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2-4 Optimization ProceduresThis section presents optimization procedures for a Cold Start of a 3G1x Voice only network as well as a

combined 3G1x Voice/Data network. The optimization procedures for some common migration scenarios

are discussed later in the document.

The primary optimization techniques are the same for both configurations. These include developing proper

neighbor lists; antenna and BCR adjustments to improve coverage and reduce Pilot pollution; adjustingsearch windows based on propagation and cell design; fine-tuning handoff thresholds to meet exit criteria

based on drop calls, FER and access performance. The difference in the procedures results from several

sources, such as, data collection equipment used, metrics evaluated and optimization problems

encountered.

2-4.1 RF Optimization for Voice only Cold StartThere are various steps involved in optimizing a network. It mainly consists of a series of drive tests to

collect physical layer and over-the-air messaging information. The data is analyzed to improve

performance by arriving at proper parameter values. Some of the parameter adjustments may require

iterations to attain acceptable performance.

The data is collected under unloaded and loaded RF loading conditions. The loading procedures are

described in the following sub-section along with the tools utilized to simulate loading. In subsequent sub-sections, we specify Test equipment required for data collection and a list of software aids used for

analysis.

Using these tools and methods, sub-section 2-4.1.5 specifies the actual set of procedures utilized for drive

test optimization. The procedures consist of a series of performance tests conducted to optimize the

performance of the network.

2-4.1.1 Loading Procedures

While it is the first right step to optimize a network under unloaded conditions, a follow-on testing is

needed to evaluate the impact of loading and to fine-tune performance as necessary. This helps prepare

network for commercial operation when it will be loaded with actual users.

Note that loading here refers to RF stress testing, not hardware or software testing of the infrastructure. One

way to load is to employ real users. However, this could become very expensive and logistically intensive.

Further, it would not be trivial to attain desired loading levels in a consistent manner. As proposed here, the

loading is attempted using simulated techniques. There are different methods employed on the forward and

reverse links as stated below.

2-4.1.1.1 Forward LinkThe forward link loading is simulated using Orthogonal Channel Noise Source (OCNS). As the name

suggests, it keys up transmission on orthogonal Walsh Codes to generate interference. It only operates on

the forward link. It is similar to a forward link of a voice channel, except that there is no power control

feedback mechanism from a phone.

The flexibility of OCNS is its ability to generate consistent interference based on a specified number of

users and dgu level per user. OCNS can be configured either in constant gain mode or variable gain mode.In the constant gain mode, the gain is held constant throughout OCNS transmission. In the variable gain

mode, the gain is scaled based on an assumed voice activity factor. Further the gain is also varied to

generate a distribution around the voice activity factor. RF Engineers typically use OCNS in a variable gain

mode to capture some dynamics of a real user.

OCNS is activated by typing following commands on the TIpdunix prompt of the ECP RTR shell:

To start


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OCNS:CELL ;START

To add users

OCNS:CELL , SECTOR , CARRIER ; USERS , DGAIN , PCV

To stop

STOP:OCNS;CELL

The input fields need to activate OCNS are cell #, sector #, carrier #, number of users and digital gain units

(DGU). The PCV on/off setting sets the variable gain mode on or off. When it is off, the constant gain

mode is activated. By default, that is, if PCV option is not specified, variable gain mode is assumed.

The amount of loading to be used during loaded testing is usually specified in the contract. It is derived

based on total Erlang loading the system is designed to handle as well as assuming average power

consumed by a user. Any loading generated by the actual test user(s) is subtracted. Since different systems

may utilize different link budget, Erlang loading and average power consumption assumptions, the loading

levels may vary and are not specified here.

2-4.1.1.2 Reverse LinkOn the reverse link, there is no concept of orthogonal loading. As the number of users in the vicinity of a

cell increases, so does its total received power on the reverse link. One way to simulate this loading is toinsert attenuation on the mobiles transmit path. This attempts to account for a fixed static increase inmobile transmit power, as it may happen with real users where cell site commands them to increase theirtransmit power to overcome loading.

Standard RF kits provided by the Tools Group have a separate attenuator on the mobile reverse transmitpath (known as Mobile Tx attenuator) to simulate loading. It is a variable attenuator with step size of 1dB and typically ranging from 0-60 dB. Similar to the forward link, the actual loading value is specified inthe contract and is based on several assumptions such as designed Erlang loading relative to reverse linkpole capacity.

Note that for a given RF kit and a given phone, it is necessary to compute proper attenuation value for anunloaded case after accounting for various losses in the assembly as well as sensitivity of the phone. For

the loaded tests, the attenuator should then be increased to account for the loading per the contract.

2-4.1.2 Data Collection Tools

There are two main tools utilized to collect data. At the mobile end, an RF data collection kit is utilized tocollect RF parameters as well as messages from the phone. This kit is described in section 2-4.1.2.1.

The other tool is RF Call Trace (RFCT). It is completely based on software. It is run to collect RFparameters from the cell. It is a simple command line tool described in section 2-4.1.2.2.

2-4.1.2.1 Mobile data collection toolkitThe test set-up for 3G1x Voice optimization is very similar to that for 2G. Figure 1 shows a schematicdiagram of standard components in a RF kit.

The tool kit provides efficient and reliable collection of mobile data. A standard RF tool kit provided byTools Group includes:

- A reference antenna with known gain magnetically mounted to roof of test vehicle- A characterized 3G1x capable test mobile with connector to provide interface to separate roof-

mount antennas- An attenuator (MRx) placed between phone and antenna to account for antenna gain, cable

loss and in-vehicle penetration loss in the forward liink- An attenuator (MTx) placed between phone and antenna to account for antenna gain, cable

loss, in-vehicle penetration loss, and loading on the reverse link.


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- Two 4-port circulators to insert the attenuators (MTx and MRx) on respective links

- Isolation box to provide convenient test fixture to hold phone and to ensure test phone is well

shielded

- Laptop for CAIT mobile data collection software along with necessary hardware interfaces to the

mobile CAIT allows display and logging of mobile RF parameters and messaging. CAITstands for CDMA Air Interface Tester and is provided by Qualcomm Inc.

- GPS Unit including magmount antenna with interface to CAIT laptop to log position information

Although not necessary, a mini-van is used typically as the drive test vehicle to house the RF kit.

CAIT configuration and loggingFollowing steps are needed to log mobile data via CAIT:

- Launch CAIT application in Windows- Configure CAIT to look for the phone on proper COM port via Options Configure CAIT

Phone menu selections.

- Hit F5 key to bring Logmask section. Set it to 23E00001841F0- From the Logging Status window, select proper logging directory- Launch the Call Monitor dialog box and configure it as follows:

o Enter the number to dial for the Markov callo Set the Call type to 8K Markovo Set all call timers and call count to 0o Check the Autolog During Calls option offo Enable the Redial on Drop selectiono In order to start a call, click on the Begin calls. If the call drops, CAIT will automatically

redial. At the end of the test, press Stop Calls on the Call Monitor to end the current calland stop automatic redial.

- In order to turn the logging On, press Alt+L. Pressing Alt+L again toggles the logging Off.

Mobile configuration- Ensure that the phone is programmed with proper Preferred Roaming List, MIN, SID and NID- Phone has two UARTs (COM Ports). Ensure that the its Serial I/O configuration is such that

UART1 represents Data (DS) and the UART2 represents Diagnostics interface. This can beverified from the handset by pressing Menu 7 9 1 (Port Map). The handset displayshould show U1 U2 .

- Set the baud rate of the phones diagnostic UART to 115200. This can be accessed from thehandset via Menu 7 9 3 (Diag Baud) and cycling through the various available speeds until115200 is seen. Hit OK to select it.

Isolation

box

Mag -mount

Circulator

Mobilehone

CAITla to

GPSUnit

Circulators

MTx MRx

Attenuator Box

Figure 1: Sketch of RF Data collection Tool kit


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RFCT number of CEs

Setting up LDAT 3G

Before creating any datasets, LDAT 3G should be setup for the specific needs of the market using the

procedure below.

Select Defaults menu item from the Configure menus, and Defaults window will show up.

On the Dataset tab, update the dataset name and browse to the default-working directory. It issuggested to use C:\DATA as the working directory. This window does not allow the user tocreate a new directory, the working directory must be created using Windows Explorer.

On the Cells tab, select the cells.mdb file to be used for this market. To create a cells.mdb file, seesection Creating a Cells Database

On the Scenario tab, update the default Scenario Name, Pilots Above Threshold and Bin Sizefields as needed.

On the Map Files tab, select the MapInfo street files for the market.

On the Metrics tab, select default metrics that should be calculated during dataset creation. Duringnew dataset creation, these metrics will be selected as default, but the user will have a chance toupdate the list before the creation of the dataset. LDAT 3G only calculates the metrics requestedby the user during database creation. However, the other metrics can also be requested after thedataset is created. In this case LDAT will go through the calculations first, then show the desired

plot. To save time, user should select metrics that are used the most during the dataset creation. On the Themes tab, the ranges and the color codes for the ranges are defined for each metric. The

user can update these values. However, having different colors in different markets can causeconfusion as the engineers move from market to market. Therefore, these setting should not bechanged unless there is specific customer need.

Creating a Cells Database for LDAT 3G

Run Cells Database tool from Start->Programs->LCAT->Lucent CellsDB Analysis Tool

Select New from the File menu

Enter a file name.

Click Save, and a new Cells Database will be created.

Add ECPs, Cells and sectors using the GUI of the Cells Tool.

Creating a Cells Database for LDAT 3G using the cells.txt file

Run Cells Database tool from Start->Programs->LCAT->Lucent CellsDB Analysis Tool

Select Cells.txt from the Import menu

Select the cells.txt file you would like to import, and click OPEN

A cells.mdb file in the same directory as the cells.txt file will be created.

Creating a Dataset in LDAT 3G

Copy all CAIT and RF Call Trace files, if applicable, to appropriate folder under the workingdirectory.

Open LDAT 3G, click on File, then New Dataset, this brings up the Dataset Creation window

Under Dataset Name enter dataset name. Click on Browse and select the folder where the data isas the working directory. Click Next

This will open the Select Data File window, now click on Add Files, choose the files and clickNext.

This will open the Select Cell data window. If needed, click on Browse, choose the cell file andclick next.

This will open the Enter Scenario Name and Select Parameters window, now enter a new Scenarioname, Change the Pilots above Threshold if required, set the Bin Size to 100 Frames. Click next.

This brings up the Select Map File window. If needed, click Add Files and add the required streetmaps. Then click next


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The next window is Select Metric to Generate, check the required metric/s and click Finish. LDAT3G only calculates the selected metrics initially, however this does not mean the other metrics can notbe plotted. When an uncalculated metric is selected the first time, LDAT 3G will go through theoriginal data files and update the database with the needed information before plotting the metric.Therefore the original data files should not be moved after the creation of a dataset.

This will start the dataset creation process.

After the dataset is creation, use the Map, Histogram or Scatter menus to select a metric to beplotted.

Creating a new scenario in LDAT 3G:In LDAT 3G, a dataset can have different scenarios. A dataset is a collection of data files, a scenario isdifferent bin size on a dataset. To create a new scenario on an existing dataset follow the instructionsbelow:

Open the dataset of interest from File->Open Dataset

Once loaded, select File->New Scenario, this will open the Scenario Creation wizard

Enter a Scenario Name, select the Pilots Above Threshold and select the bin size. Click Next

If needed, click Add to select the street file. Each scenario can have a different set of street files. ClickNext

Select the metrics to be created initially. Click Finish.

The new Scenario will be created, and it will be added to the Scenario Name pull down box in the toolsbar. Make sure you select the correct Scenario when a dataset has more than one scenario.

NPAR/WPAR/Friendly Viewer

Use NPAR5108 or greater to parse the mobile file(s) for special problem investigation. The parsingcommand is:Npar5108 >

If the windows version of NPAR, called WPAR, is available to the RF Engineer, follow the steps below toparse the mobile file instead of using NPAR5108:

- Click on WPAR icon to invoke the application- Click on File -> Open, this brings a window to choose mobile file, select the desired file and hit

OK. WPAR will parse the mobile file into a readable format

Note: WPAR does not save the parsed file, so before you exit WPAR, you have to save the parsed file e.g.mtotal.par.

Qualcomm will eventually stop supporting NPAR5108/WPAR and Friendly Viewer will be the alternative.This is a windows based application. To run it, exercise the following steps:

- From the File menu, Select Logfiles- From the dialog box, browse to the folder where logfiles are stored and choose appropriate

logfiles. Click OK.- The Friendly Viewer will parse the logfile and display the contents using its own text browser.

3gtool3gtool is another data analysis tool that provides several outputs to aid in the analysis. The key outputs

include: Dropped location alert Location and time stamp

Weak Pilot alert Location and time stamp

Missing Neighbor List alert Location and time stamp

Origination success rate

Termination success rate

Potential reason, Latitude, Longitude and time stamp for Origination and Termination attempt failures

Dropped call rate


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3gtool will automatically determine if the file is an origination file or a termination file and output

necessary information such as mappable information about drop calls, if any. To use 3gtool, type the

following in the directory where the mtotal.par file is (e.g. 3Gtest):

C:\>3Gtest\3gtool mtotal.par > mtotal.out

The output file, mtotal.out, contains the information about each individual origination or termination,

summary and failure mode statistics.

Note: A batch file can be used to combine the commands for NPAR and 3gtool in one step. 3gtool will be

integrated in LDAT 3G 1.3 such that the statistics can be directly produced from CAIT logfiles without the

intermediate NPAR/WPAR parsing steps.

Geobin

Geobin is a tool typically utilized for warranty testing. It slices the data into geographical bins of user

specifiable size (X by Y meters). The data is merged per bin and a statistic such as average is computed.

Certain number of worst bins are typically discarded and the rest of bins are utilized to compare against a

given set of criteria.

For running GeoBin on 3G-1X handset data, before LDAT version 1.3 is available, data processors should

use the old (2G based) tool. Here is a high level procedure: Open the database created by LDAT 3G

Export the data of interest from BinnedData table to a text file

Run Geobin on the text file

For more details on this step, visit the web page http://rf-optimization.wh.lucent.com/geobin

For LDAT 1.3 and later, Geobin tool will be available from the "Tools" menu of LDAT 3G, which will

generate the report.

2-4.1.4 Personnel requirements

The human resource requirements can be segregated per the work function. The drive test optimization

consists of two main functions Drive test data collection and analysis. Accordingly, the minimumpersonnel requirements can be identified as follows:

1. Driver: As the name suggests, the person will be responsible for driving the test vehicle. He can takeon additional responsibilities such as set up/disassembly of the data collection equipment in the van.He is also responsible for navigation.

2. Data collector: The person rides in the test van collecting the data from various tools in the van. Hemay be responsible for setting up any tools at the infrastructure such as OCNS, RF call trace, etc.Additional responsibilities include transferring data to the data analysis person, maintenance of thedrive test equipment, and depending on the skills participate in the analysis.

3. Data Analysis/Leader: The person is responsible for analyzing the data and ensuring parameteradjustments. This person also plays a key role in the entire optimization process as the Test Leader.

Additional duties include: ensure proper selection of drive routes with the customer, hire/manage datacollection personnel, schedule data collection, lead problem area troubleshooting and apprisecustomer/upper management of progress.

2-4.1.5 Performance Tests

Optimizing a CDMA system mainly consists of executing a series of tests to evaluate performance of theclusters/network while making necessary parameter adjustments at each step. The tests can be construed toconsist of sequential phases with each leading to better levels of performance. Some tests may neediterations to attain acceptable performance, especially, in certain challenging problem areas.


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There are three major tests for optimizing a 3G1x Voice Cold Start system. The first two tests are executed

on individual clusters while the third is performed after integrating the entire system. Additional tests may

be executed optionally based on contractual agreements with the customer. These may include dropped

call, origination and termination tests.

When the tests are concluded, the system is ready for commercial operation. Below we detail procedures

associated with each of these tests.

2-4.1.5.1 Unloaded Pilot Channel Coverage TestThe objective of the Unloaded Pilot Channel Coverage Survey Test is to measure the forward channel pilot

coverage for unloaded conditions, with all sectors in the cluster transmitting pilot, page, quick paging, and

sync channels. Based on the measured performance, some parameter adjustments can be made to improve

coverage, fix neighbor lists and fine tune performance in local areas. The parameters to be adjusted include

the Primary and Secondary parameters. For these tests, a RF Kit for 3G1x Voice testing is placed in a

roving test vehicle and driven over selected drive routes. The CDMA phone will be maintained in a

continuous traffic state as much as possible. The drive routes should include the most heavily traveled

highways and primary roadways in the coverage area of the cluster. The drive routes should also cover

areas with substantial handoff activity. The routes should include areas where signal strengths may be

weakest due to obstructions; for example, coverage in valleys, underpasses, tunnels, urban corridors, etc.

Particular emphasis will be placed on marginal coverage areas and places with multiple pilot coverage aspredicted by CDMA planning software (CE4).

2-4.1.5.1.1 Entrance Criteria1. Necessary steps have been taken to ascertain clear spectrum in/around the cluster before transmitting

CDMA signal.

2. Coverage prediction plots from planning tools, such as CE4, must be prepared for the coverage area of

the test cluster.

3. CDMA equipment for the test cluster must be installed, configured, and operational. Sectors tests

verifying rudimentary call originations, terminations, and sector-to-sector softer handoffs should have

bern performed on each cell prior to this phase.

4. Translations parameters for the sectors in the cluster should have been entered and verified using the

Recent Change Verification (RCV) procedures. The RF translation parameters should be configured

per recommended values in the various Forward Link Translation Applications Notes.5. A best guess Neighbor List configuration is entered into the translations. The section on Primary

parameters specifies some simple results for neighbor list construction.

6. Transmit powers of pilot, page, quick paging, sync, and traffic channels should be calibrated at each

sector in the cluster as described in the Forward Link Translation Applications Note [3].

7. CDMA mobiles used in the testing should be tested for compliance with IS2000 and the IS-98 Mobile

Station Performance Specification.

2-4.1.5.1.2 Test ConditionsEach sector should be transmitting pilot, page, quick paging and sync channels at the nominal levels. No

other CDMA traffic should be on the test cluster other than the test phones.

The drive routes will be representative of typical usage in the system. As a minimum, they will consist of

all primary and secondary highways as well as major streets. Drive routes should cover highwayinterchanges, exit/entrance ramps to arterial roads, over water bridges, raised highways, and other areas

where reliable CDMA coverage is mandatory.

The drive test will utilize a phone making a continuous Full rate Markov call in RC3 mode. If the call drops

during the drive test, it will be re-originated (make appropriate selections in CAIT for automatic re-dial on

drop).

2-4.1.5.1.3 Test Procedures


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The procedure to be used for the unloaded pilot channel coverage surveys is listed below. Follow the

instructions in section 2-4.1.2 for CAIT configuration as well as CAIT and RFCT logging.

1. Install the 3G1x Voice RF Kit in the test vehicle. Ensure that CAITs Logmask is set correctly. Checkto be certain that the CAIT is logging GPS position data by observing the output information from theGPS server.

2. At the beginning of each drive run, initiate RF Call Trace at the cell site to log performance statisticsfor the test phone.

3. Start CAIT logging by pressing Alt+L.4. Click on Begin Calls of CAITs Call Monitor dialog box to start making 8K Full Rate Markov calls

(RC3).5. Begin drive testing.6. At the end of the run, stop RFCT logs. Ensure that the run does not exceed 4 hours. Else, stop RFCT,

run FTrfdump process and restart RFCT.7. Also, at the conclusion of the drive route, press Stop Calls on CAITs Call Monitor dialog box and

toggle CAIT logging off by pressing Alt+L.8. Save the log files and transfer them to the data analysis computer.

2-4.1.5.1.4 Data AnalysisData analysis of the unloaded pilot channel survey data will primarily consist of processing the datathrough the post-processing software LDAT 3G. The resulting files can be used to display information such

as Max Finger FCH Pilot Ec/Io as a function of location. The software allows overlaying the field data on astreet map. The resulting pilot coverage maps can be compared against predicted levels from RF planningtools.

The pilot coverage maps should be used to validate the RF design for the test cluster. Because themeasurements were made under unloaded conditions, they represent an ideal, best-case condition. Underfull loading conditions, observed pilot Ec/Io levels would be much lower than the unloaded measurementvalues. Any coverage holes, which exist for the unloaded measurements will be enlarged once the systemmatures and becomes loaded. If substantial areas of poor pilot coverage exist in the measured coveragearea for the test cluster, then RF design alternatives should be considered to remedy the problem areas.Possible solutions include changing pilot powers, changing antenna patterns, reorienting antennaboresights, and adding additional cells or repeaters.

If geographical areas exist where more than 3 pilot signals are consistently o

Documents

3G1x RF Optimization Guideline