Compact pattern based dynamic channel assignment for cellular mobile systems

Abstract

A new compact pattern based dynamic channel assignment strategy called CP-based DCA is proposed. The strategy aims at dynamically keeping the cochannel cells of any channel to a compact pattern. A compact pattern of a channel is defined as the pattern with minimum average distance between cochannel cells. CP-based DCA consists of two phases; channel allocation and channel packing. Channel allocation is used to assign an optimal idle channel to a new call. Channel packing is responsible for the restoration of the compact patterns and is performed only when a compact channel is released. Simulation results indicate that the CP-based DCA always performs better than the borrowing with directional channel locking (BDCL) strategy. The latter being the strategy that gives the lowest blocking probability among the class of known strategies that do not require system-wide information. In our designed example, CP-based DCA is shown to have 3% more traffic-carrying capacity than that of the BDCL in case of uniform traffic and 9% more traffic-carrying capacity in case of non-uniform traffic, both at a blocking rate of 0.02. Besides, the number of channels reassigned per released call in CP-based DCA is at most one and is therefore another advantage over BDCL.