Channel assignment with limited channel-sharing in cellular networks-a homogeneous analysis
Tai-Kuo Woo · IEEE Transactions on Communications · 1997
The granularity of frequency reuse of the conventional approach for channel assignment is a cluster (a partition of a coverage area). That means that the channels used in cells (partitions of a cluster) within the same cluster are distinctive. In this paper, we propose a different approach for channel assignment such that the channels are reused among cells in the same cluster. However, there are two constraints on the reuse of channels in a cluster to keep the cochannel interference in check. First, adjacent cells are not allowed to use the same channels. Second, the number of "one-hop-away" cells assigned the same channels is limited. The approach we take is based on the theory of finite projective planes. By mapping the sets of points of a finite projective plane to the channels assigned to a cell, channel reuse is achieved within a cluster. The performance evaluation is done in three parts. In the first part, we show that the channel reuse efficiency of the proposed approach is higher than that of the conventional approach with a tradeoff of a lower signal-to-interference (S/I) ratio. In the second part, the S/I is kept the same, and we demonstrate that the proposed approach has a higher channel reuse efficiency when the cluster size is reasonably small. In the third part, the worst case analysis for the situation that mobile users roam around the cell boundary is illustrated and a strategy of channel allocation is provided to avoid the worst case conditions.