Outage Analysis for Full-Duplex Cooperative Networks with Optimal Relay Selection

New applications associated with the Internet of Things (IoT) often involve cooperation and relaying among many autonomous wireless devices. This should be supported by wireless transmission schemes in physical layer. Different from half-duplex (HD) cooperative networks, the relay and destination in full-duplex (FD) cooperative networks suffer from the loop interference and the direct link interference respectively, since all the nodes work on the same frequency band simultaneously. In this paper, we first investigate the relay selection strategies by taking the direct link interference into consideration. Then, we analyze the outage probabilities of relay selection schemes for FD cooperative networks under amplify-and-forward (AF) and decode-and-forward (DF) protocols. Numerical simulations are performed to verify the analytical expressions and make a comparison between the proposed selection schemes and the conventional schemes. It is shown that significant performance gain can be achieved by the proposed schemes compared with the conventional schemes without consideration of the direct link interference, especially in high signal-to-noise ratio (SNR) regime.