Optimizing Interference Cancellation in Cooperative Wireless Networks with Relay Selection

Successive interference cancellation (SIC) is a decoding scheme that allows multiple sources to transmit simultaneously over the wireless medium to a single destination. The power level that each symbol is received has a direct impact on the performance of SIC. Thus, optimizing SIC entails careful power allocation at the transmitting sources or in a network setup, the scheduling of the sources that will transmit simultaneously. In this paper we consider a two-hop multi-relay cooperative network setup. In this setting instead of pro-actively scheduling the sources or employing power allocation, we investigate a reactive scheme for optimizing the performance of SIC that operates after the sources have transmitted. We propose distributed relay selection as the means to improve SIC. We investigate different relay selection policies depending on channel state information (CSI) availability at the relays and the performance optimization objective. Simulation results for our SIC-aware relay selection schemes demonstrate that it offers a viable option for improving the performance of SIC.