Interference cancellation in in-band full-duplex underwater acoustic systems

In-band full-duplex (IBFD) radios can double the spectral efficiency in theory, and their feasibility has been demonstrated by using advanced cancellation methods for terrestrial communications. We investigate the feasibility of acoustic IBFD in the underwater acoustic (UWA) channel, to enhance the spectral efficiency in the severely bandwidth-limited aquatic environment. We discuss the challenges of implementing IBFD UWA systems. Further, we propose an acoustic-specific cancellation scheme to deal with the strong multipath self-interference in IBFD UWA systems. We show, through simulations, that the proposed scheme can effectively suppress different types of interference.