CDMA 1X Network Expansion Guide

7/28/2019 CDMA 1X Network Expansion Guide

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PTCL CDMA 1XNetwork Expansion

Guide

Huawei Technologies Co. LTD.

All rights reserved


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Table of Content

Chapter 1 Introduction to PTCL network ....................................................................................... 31.1 Introduction ........................................................................................................................... 3

Chapter 2 Network expansion criterion ......................................................................................... 32.1 Capacity related Criterion ..................................................................................................... 3

Chapter 3 Network expansion suggestions................................................................................... 73.1 Overall Suggestions.............................................................................................................. 73.2 Network Expansion Methods................................................................................................ 7

Load balancing between neighboring sites ................................................................. 7 Adding carriers to overloaded sites ............................................................................. 7

List of the tables

Table 1 TCH congestion criteria......................................................................................................... 4Table 2 average forward Tx power..................................................................................................... 4Table 3 TCH (Excluding HO) (CS-FCH)............................................................................................. 5Table 4 TCH (Excluding HO) (PS-FCH)............................................................................................. 5Table 5 CE Traffic Density-PS SCH................................................................................................... 6


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Pakistan PTCL Network Expansion Solution Proposal Page 3 of 7

2010-3-31 All rights reserved Page 3 of 7

Chapter 1 Introduction to PTCL network

1.1 Introduction

This document is produced by Huawei to describe Huawei Network expansion guidelines for

PTCL WLL system. Main content include 2 parts: Huawei network expansion criterion and

network expansion solutions.

For a network expansion project, precise analysis can ensure project steady, controlled, and

cost-effective. Based on rich experiences globally, Huawei build a comprehensive criterion

for expansion project, will be detailed described in this document.

Chapter 2 Network expansion criterion

2.1 Capacity related Criterion

In CDMA network, network capacity is limited by the Um interface (air interface) resources.

Based on our rich experience of global network operation and deeply research on network OM

(Operation Measurement) data, here we conclude the following indicators are thoroughly

related with network capacity;

I. Busy hour TCH congestion ratio

This index represents the probability of TCH request failure due to insufficient radio

resources when the users originate calls or handoff. It is the basis of network expansion.

Related index: TCH Congestion Ratio[%]:


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Definition

A measurement of radio TCH congestions.

TCH Congestion Ratio indicates the situation of TCH

assignment during call setup. It differs from Call Resource

Allocation Failures. The latter refers to failures of allocating all

call resources, such as radio resources, transmission,

hardware, and so on.

Unit NoneType Calculated item

Measurement

method By calculation

Formula (TCH Assignment Requests Successful TCH Assignments)/ TCH Assignment Requests x 100%

Table 1 TCH congestion criteria

To ensuring the user feelings and network performance, in terms of the single carrier sector,

the busy hour TCH congestion ratio is suggested below 2%.

When busy hour TCH congestion ratio >= 2%, the network expansion is required.

II. Busy hour forward average transmit power

This index represents the busy hour forward average transmit power of single carrier sector,

and is equal to the sum of powers of all forward channels (including overhead channel and

traffic channel).

Related index: Forward load of carrier [%]:

DefinitionForward load of current carriers. It is the ratio of the current transmit

power of carriers to the maximum transmit power.Unit None

Type Original item

Measurement

methodBy average

Measurement

point

The RRM module obtains the transmit power of carriers from the

Common Measurement Report message sent by the BTS every one

second, and then calculates the forward load of current carriers.

Table 2 average forward Tx power


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When carrier/sector rated power is 20W, busy hour forward average transmit power is

suggested below 43dBm.When the busy hour average transmits power exceeds 43dBm, it

indicates that the available power resources of the carrier sector are insufficient and access

restriction may arise to ensure the service quality of in-service subscribers;Meanwhile, when forward Tx power is kept approaching 43dBm, it also means there are certain

edge coverage users, single user consumes too much forward powers; power amplifier long

time keep working on additional overload, which will greatly affects the lifecycle of power

amplifier. To solve this problem, adding carriers is suggested;

III. Busy hour TCH traffic (excluding HO)

This index represents the traffic load of single carrier sector.

Related index: Density of Traffic Carried on TCH (Excluding HO) (CS-FCH)

Definition Density of CS traffic carried on FCHs, excluding HOs.Unit ErlType Calculated item

Measureme

nt Method By calculation

Formula TCH Seizure Duration (Excluding HO) (FCH-CS) / (measurement

period x 60)Table 3 TCH (Excluding HO) (CS-FCH)

Related index: Density of Traffic Carried on TCH (Excluding HO) (PS-FCH)

Definition Density of PS traffic carried on FCHs, excluding HOs.Unit ErlType Calculated item

Measureme


Formula TCH Seizure Duration (Excluding HO) (FCH-PS) / (measurementperiod x 60)

Table 4 TCH (Excluding HO) (PS-FCH)


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Related index: CE Traffic Density-PS SCH

Definition Density of CE traffic carried by F-SCHs.Unit

Erl

Type Calculated item

Measureme


Formula CE Traffic Density-PS SCH = CE Seizure Duration-SCH /(measurement period x 60)

Table 5 CE Traffic Density-PS SCH

Busy hour TCH traffic (excluding HO) = Density of Traffic Carried on TCH (Excluding HO)

(CS-FCH) + Density of Traffic Carried on TCH (Excluding HO) (PS-FCH) + CE Traffic

Density-PS SCH

According to Pole Capacity formula and according the experiences of global CDMA

commercial networks operation, busy hour TCH traffic (excluding HO) is suggested as 21

Erl.

If busy hour TCH traffic (excluding HO) exceeds 21Erl, it indicates that the carrier sector is

overloaded. When the traffic volume increases, network quality will get worse, network

congestion occurred, may some subscribers couldnt access the network. And meanwhile,

excessive TCH traffic load conduct the consequences as, high CDR(call drop ratio), quality of

service (QoS) degradation, finally affect subscriber perceived service; to solve the problems,

adding carriers is suggested;

IV. Capacity criterion summary

The basic three criterion deteiled the network expansion standards, and each of which

is basic requirement that we suggested; If any one of the previous three conditions is

met, the network expansion is required.


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Chapter 3 Network expansion suggestions

3.1 Overall Suggestions

For the carriers whose TCH traffic (excluding HO) exceeds 21Erl, the emergent expansion is

recommended.

For the carriers whose TCH traffic (excluding HO) ranges from 18Erl to 21Erl, the expansion

planning is performed.

For the carriers whose busy hour average transmit power exceeds 43dBm, the expansion

planning is performed.

3.2 Network Expansion Methods Load balancing between neighboring sites

Load balancing between carriers

Handoff region optimization (to reduce handoff ratio and save resource)

Adding carriers to overloaded sites

Adding new sites to meet capacity requirements

Documents

CDMA 1X Network Expansion Guide