Capacity optimizing channel allocation scheme supporting multiple services with mobile users in cellular system

In this paper, we study the performance of mobile users, in terms of call blocking and dropping probabilities, with our proposed idea of channel partitioning (CP). CP is based on the fact that different services may require different signal-to-interference ratios, and thus different reuse factors. We apply this CP with fixed channel allocation (FCA) scheme called fixed channel partitioning (FCP) in cellular systems. With FCP scheme, each cell is allocated two or more sets of channels. Each set of the channels supports a service in the way that the required reuse factor for that service could be satisfied. A three-dimensional Markov chain is first developed to analyze the impact of the mobile user. Then a simpler model, which can be used to estimate the numeric results from the closed-form solution, is presented to make the analysis easy. Finally, the analytical results are verified with simulation results. The results of this paper show that, for equal voice and data call arrival rate, the proposed FCP scheme can provide about 32% capacity improvement at 1% grade of service (GoS) as compared with FCA scheme. The changing of mobile speed and GoS factor do not affect this improvement. Our proposed FCP scheme could apply in current GSM, GPRS EDGE and future cellular OFDM systems, in which reuse factor plays a very important role