Adaptive Relay Selection Algorithm Based on Network Coding in 802.16m Network

In 802.16m network, mobile station can choose different transmission schemes: direct transmission, cooperative transmission, or cooperative network coding transmission. Different transmission scheme has different effects on network performance. Particularly relay selection method affects network throughput and the amount of network resource for cooperative transmission and cooperative network coding transmission. In this paper, a novel relay selection algorithm, named RSTRA (Relay Selection algorithm combined Throughput and Resource Allocation), is proposed for different network load. When few mobile nodes request to transmit, which means the amount of network resource is enough, RSTRA will select the correct relay and transmission scheme in order to achieve maximum network throughput. And if a lot of mobile nodes want to transmit, RSTRA will optimize the total amount of resource allocation while satisfying all requests. Simulation results show that RSTRA can get higher throughput than CNCRA algorithm in light network load and it needs less resource amount to achieve the same throughput with CNCRA in heavy network load.