Distributed dynamic channel allocation algorithms in microcells under light traffic loading

Abstract

We consider distributed dynamic channel allocation (DCA) algorithms for wireless cellular networks. Two algorithm extremes are the baseline of our investigation: Theaggressive type algorithms, where channel assignments of ongoing calls may be reconfigured to make room for a new access request; and thetimid one, where reconfigurations are not permitted. While, generally, analyses of DCA algorithms appear very difficult, we show here that a light traffic analysis can be tractable. For that realm, we derive performance expressions showing significant reductions in access blocking probability when an aggressive, rather than the timid, access algorithms is used. The relative efficacy of various algorithms that we present can be analytically probed in this range. Certain aggressive algorithms are observed to attain the best performance possible therein. The advantage over timid is particularly substantial for planar cellular arrays. These results hint that there may be significant channel savings, associated with the type of aggressive algorithms described here, in the important, yet much more difficult to analyze, operating realm where the blocking, but not necessarily the loading, is low; and lead us to devise a family of hybrid DCA algorithms that are both stable and low blocking.