A time-reversal based digital cancelation scheme for in-band full-duplex underwater acoustic systems

In-band full duplex (IBFD) can theoretically double the throughput of communication systems, and its feasibility has been demonstrated in wireless radio design. It is a promising alternative for the severely bandwidth-limited underwater communication system since it exploits both the temporal and spectral efficiency to the most. Self-interference cancelation is the primary challenge in IBFD's implementation. In this paper, we propose a novel digital cancelation scheme combining time-reversal (TR) and soft-decision feedback turbo equalization (SDFE), which eliminates both the residual self-interference from local transmission and intersymbol interference (ISI) of desired received signal at the same time. Simulation results show that the proposed method outperforms the conventional one with a lower BER under identical circumstances.