Frequency allocation scheme to maximize cell capacity in a cellular system with cooperative relay

Abstract

When deploying the fixed relay stations (RSs) in a cellular system, additional co-channel interferences occur necessarily. To avoid the co-channel interferences, an effective frequency allocation (FA) scheme is essentially required. Cooperative relay can achieve the diversity gain as well as coverage extension of the cellular system. FA schemes with non-cooperative relay have been widely studied, but little research has been done for those with cooperative relay. Since cooperative relay is that RS and base station (BS) simultaneously transmit the same signal using the same time and frequency resources, FA scheme with cooperative relay has different FA patterns compared with that for non-cooperative relay. In this paper, we propose an improved FA scheme with cooperative relay in the system. The proposed scheme can maximize the cell capacity through minimizing co-channel interferences and achieving the cooperative source diversity gain. Through a computer simulation, we demonstrate the proposed FA scheme with cooperative relay can increase average cell, user, and edge user throughputs compared with those for conventional systems under the IEEE 802.16j environment.