Handoff Schemes in TDMA/FDMA Systems

Abstract

This chapter addresses the issue of how to provide seamless hand-off to mobile users, under the constraint of limited resources, in a multimedia wireless network. We adopt the concept of the guard channel (GC) scheme, which gives preferential treatment to the high priority calls, including handoff calls, by reserving a fixed number of channels exclusively for them. However, such schemes decrease the handoff dropping rate at the cost of increasing the blocking rate for other users due to poor channel utilization. To deal with this challenge, we introduce a dynamic resource reservation module to efficiently estimate the resources needed to be reserved for high priority calls, by using the SNR and distance information of a mobile in the neighboring cells.