2G/3G Inter-RAT Handover Performance Analysis

One of the most interesting UMTS networks features is their integration with the 2G networks that provides seamless end-to-end services. Current widely deployed 2G and 3G networks provide interRAT (inter radio access technology) mechanisms enabling interoperability between them in a manner that is almost transparent to the subscriber. These enable maximum benefit from 3G services while ensuring wireless coverage continuity in geographically extended networks, where 3G coverage halls exist. These mechanisms include interRAT idle mode reselection, interRAT dedicated mode reselection for PS (packet switching) services, and interRAT handover for voice calls. The aim of this paper is to evaluate the interRAT handover (HO) performance between 2G and 3G networks. Analysis of the performance would be presented in the two HO directions. We propose an analytical model where the introduction of the 3G cell´s load as one of the HO initiation parameters is considered. In addition, an interRAT HO ping-pong defensive mechanism is proposed.