On the Performance of X-Duplex X Relaying
Abstract: In this paper, we study an X-duplex X duplex relay system with one source, one amplify amplifyand-forward forward relay, and one destination, where the relay is equipped with a shared antenna and two radio frequency (RF) chains used for transmission or reception. X-duplex duplex relay can adaptively configure the connection between its RF chains and antenna to operate in either half half-duplex duplex (HD) or full full-duplex (FD) mode, according to the instantaneous channel conditions. We first derive the distribution of the signal to interference plus noise ratio, based on which we then analyze the outage probability, average symbol error rate (SER), and average sum rate. We also investigate the X X-duplex duplex relay with power allocation and derive the lowerr bound and upper bound of the corresponding outage probability. Both analytical and simulated results show that the X X-duplex duplex relay achieves a better performance over pure FD and HD schemes in terms of SER, outage probability and average sum rate, and the performance floor caused by the residual self interference can be eliminated using flexible RF chain configurations.