Full-Duplex Communication in Bidirectional ISAC

A bidirectional integrated sensing and communication (ISAC) system is proposed, in which a pair of transceivers carry out two-way communication and mutual sensing. The conventional full-duplex and half-duplex operations are redesigned to take into account sensing echo signals. Then, the transmit beam-forming design of both transceivers is proposed for addressing the sensing and communication (S&C) tradeoff. A one-layer iterative algorithm relying on successive convex approximation (SCA) is proposed to obtain high-quality solutions. Finally, the numerical results show that the existence of the interference introduced by sensing results in full-duplex may not always outperform half-duplex, especially in the sensing-prior regime or when the communication channel is line-of-sight-dominated.