3.1 Introduction

This chapter will show how combinations of CASs for initial access and handover in microcellular systems can decrease both the numbers of new calls blocked and the number of handover calls forced to terminate. To do this a teletraffic analysis is carried our for a microcellular system first using FCA and then using DCA.

The FCA system treats handover calls using both NPS and RCS. The analytical method used is valid for uniform and nonuniform traffic distributions. Then an extension (generalization) to the nonuniform compact pattern allocation algorithm [1] is presented as an application of this analysis.

Finally, based on this analytical method and on the extended nonuniform allocation concept, a modified version of the DCA strategy CPMCB is explained and combined with the NPS and the RCS strategies for handover for both uniform and nonuniform traffic.

The effect of mobility of users in the performance of the combination of the strategies is also assessed.

3.2 The Problem of Handovers in Microcellular Environments

A handover, of course, occurs when a call moves from one cell to another. The mobile terminal has to change its radio transmission from one BS to another. Clearly the more cell boundary crossings there are, the more forced terminationof calls there will be. This will affect the design and performance of a cellular system. This is first discussed before analyzing performance in later sections of this chapter.

Recently, the demand for wireless communications has grown tremendously. Cell sizes have had to decrease to...