Movable Antenna-Aided Two-Way Relay System

This letter investigates a movable antenna (MA)-aided two-way relay (TWR) system, in which multiple MAs are deployed at the relay to assist bidirectional communication. We aim to maximize the minimum signal-to-noise ratio (SNR) between the two terminals by jointly optimizing the MA positions and the beamforming matrix of the relay. To shed light, we first derive the closed-form upper bounds on the SNRs. Then, an efficient two-loop iterative algorithm is proposed to tackle the non-convex optimization problem, which employs particle swarm optimization (PSO) in the outer loop for antenna position optimization and utilizes maximum ratio combining/transmission in the inner loop for beamforming matrix design. Simulation results validate the effectiveness of the proposed algorithm and demonstrate the superiority of the MA-aided TWR system over conventional systems with fixed-position antennas (FPAs).