Distributed Relay Selection in OFDM-Based Cooperative Wireless Networks

In this paper, we investigate distributed relay selection in OFDM-based cooperative wireless networks. A selective Decode-and-Forward relaying strategy is adopted, in which one relay is selected to forward the entire OFDM symbol. Theoretical outage performance is analyzed and evaluated first. Then six relay selection schemes based on different selection criteria are given. The outage performance of one of the schemes coincides with the theoretical value and all the schemes need only local CSI and can thus be implemented in a distributed way. Monte Carlo simulations validate our analysis and show that significant performance gain can be obtained compared to that of direct transmission.