Telecomunicaciones

Aircom International TECHNICAL REPORT
Prepared (also subject responsible if other) No.

1 (73)

Senior Engineer Emerson Eduardo Rodrigues
Approved Checked Date Rev Reference

2006-03-286

PA1

Technical report - GPI IRAT HO

Abstract This is a technical report for the IRAT Handover and Cell reselection project being done in MTN WCDMA network in South Africa

AircomInternational TECHNICAL REPORT
Prepared (also subject responsible if other) No.

2 (73)

Senior Engineer Emerson Eduardo Rodrigues
Approved Checked Date Rev Reference

2006-03-286

PA1

Executive Summary Huawei and MTN SA performed during the last 7 weeks tests of the Inter Radio access Technology (IRAT) mobility between MTN’s 3G and 2G networks in South Africa. For the 3G to 2G handovera choice between CPICH RSCP and CPICH Ec/No can be done to trigger the handover. For the initial network launch when there is no or low load level and no major interference problems in the network CPICH RSCP gives a more stable IRAT handover from 3G to 2G. However in areas where there initially is a relatively high level of interference, such as high-rise buildings, CPICH Ec/No is a moresafe choice of measurement quantity for triggering the handover. One drawback of using CPICH Ec/No is that a relatively high triggering threshold is needed to have stable handovers in coverage-limited scenarios. This might lead to that some users at some locations move to the 2G network even though they could have reasonable 3G coverage. The choice of measurement quantity for the triggering isa matter of trading pros of one quantity for cons with the other. The decision should be taken bearing in mind the strategy of MTN current network deployment and future network expansions.

Aircom International TECHNICAL REPORT
Prepared (also subject responsible if other) No.

3 (73)

Senior Engineer Emerson Eduardo Rodrigues
Approved Checked Date Rev Reference

2006-03-286PA1

Contents 1 INTRODUCTION ...................................................................................................... 6 1.1 BACKGROUND ............................................................................................... 6 1.2 PURPOSE ..................................................................................................... 6 1.3 MTN’S IRAT MOBILITYSTRATEGY .................................................................. 7 THEORY ................................................................................................................... 8 2.1 BACKGROUND TO IRAT HO/CR ..................................................................... 8 2.2 CPICH RSCP.............................................................................................. 8 2.3 CPICH EC/NO .............................................................................................. 8 2.4 UPLINK AND DOWNLINK ................................................................................. 9 2.5 IRAT HANDOVER ........................................................................................ 10 2.5.1 U2G: Triggering of 2G measurements....................................................... 10 2.5.2 U2G: Compressed mode measurements................................................... 11 2.5.3 U2G: Handover from UTRAN .................................................................... 12 2.5.4 G2U: Triggering of 3G measurements ....................................................... 14 2.5.5 IRAT Handover strategy and possibleparameter settings ......................... 16 2.6 IRAT CELL RESELECTION ............................................................................ 17 2.6.1 U2G: Triggering of measurements............................................................. 17 2.6.2 U2G: Cell ranking ...................................................................................... 19 2.6.3 G2U: measurements...