Experimental demonstration of time reversal communication in doubly dispersive underwater channels

It is known that the conventional time reversal (or passive-phase conjugation) is not applicable to time-varying channels with large Doppler spreads. Recently a new time reversal communication technique that can simultaneously counteract delay and Doppler spreads has been proposed and tested via simulations [22]. In this paper, we present testing results from a field experiments of underwater acoustic communication, which was conducted with a fast mobile source in the Thousand-Island Lake located at Chunan, China, in December 2011. Experimental results demonstrate that the new time reversal receiver that uses a rake-like structure to compensate for multiple Doppler shifts can eliminate both Doppler spread introduced by temporal channel variations and delay spread caused by waveguide effects. As such, it provides a quite promising data transmission technique for underwater communication network.