Aggressive fuzzy distributed dynamic channel assignment algorithm

Abstract

Constraint based channel assignment schemes often rely on crisp evaluations of radio interference constraints to determine if an open channel is feasible for assignment. Such an approach has been popularly adopted to formulate fixed channel assignment (FCA) schemes, dynamic channel assignment (DCA) schemes, and more recently distributed DCA (DDCA) schemes. DDCA schemes are localized DCA schemes where every cell site is responsible for channel assignments to calls generated within that cell. The paper introduces the aggressive fuzzy DDCA (AFDDCA) scheme in which the feasibility evaluation of the constraints is soft. The scheme is in the polite mode when a perfectly feasible channel exists, and in an aggressive mode otherwise. The aggressive policy is progressive. We demonstrate that, when the traffic is heavy, AFDDCA scheme can outperform globally optimal DCA in terms of spectral efficiency while the voice quality degradation is surprisingly mild.