Multiuser detection for time-variant multipath environment

Shallow water acoustic network (SWAN) communication has been an area of active research over the recent years. Due to the wave motion, the multipath components undergo time-varying propagation delays that result in signal attenuation and phase fluctuations. Although the adaptive decision feedback equalization (DFE) structure adopting spatial diversity scheme is effective in combating against multipath fading and inter-symbol interference (ISI) problem. In a SWAN, the receiver structure has the added task of suppressing co-channel interference (CCI) from other users, where DFE structures not employing multiuser detection strategy will often fail. This paper addresses the development of a multi-user detection strategy based on multistage recursive successive interference cancellation (RSIC) to suppress ISI and CCI in SWAN. The structure is then assessed with sea-trial data and results indicate that the RSIC structure is effective in mitigating the effect of ISI and CCI.