Interference Channels With Full-Duplex Amplify-and-Forward Receiver Cooperations

This paper considers a two-transmitter and two-receiver interference channel (IC), where each transmitter sends a message to its desired receiver. In particular, the full-duplex (FD) amplify-and-forward (AF) protocol is adopted to build up the receiver cooperations: each receiver can receive the signals from the two transmitters and two receivers, and after self-interference (SI) cancellation and message decoding, it forwards them to its counterpart. With the above scheme, the equivalent channel model is analyzed, and the statistics of the accumulated residual interference and noise (ARIN), generated by the imperfect SI cancellation and the AF scheme at the receivers, is calculated by mathematical induction. Then, the achievable rate regions of both the single-user and joint decoding schemes are derived. It is proved that one-side cooperation, i.e., only one of the two receivers forwards its counterpart's signal, is optimal to achieve the best system performance. Next, to characterize the obtained rate regions, the rate maximization problems are formulated and approximately solved by a sequential parametric convex approximation (SPCA) method. Simulation results show that the proposed scheme can improve the achievable rate compared to the conventional non-cooperative scheme in several typical scenarios.