Compensation for time variance in long-range time-reversal communication

在水声通信中，与空中无线电通信不同，由于多径环境和信源或接收机的运动导致的码间干扰（ISI）导致的多普勒频移和时变信道脉冲响应是非常重要的。对于前者，时间反转（相位共轭）通信在之前的研究中已经被提出并证明是非常有效的。本文讨论了时变通信中补偿时变影响的方法，并在正常模态仿真和海上实验的基础上进行了验证。

In underwater acoustic communication, differently from radio communication in air, inter symbol interferences (ISI) due to multipath rich environment and the movement of source or receiver, which results in Doppler shift and time-variant channel impulse response, are very dominant. For the former, time reversal (phase conjugate) communication has been proposed and verified to be very efficient in the previous study. In this research, the method to compensate the effect of time variance in time-reversal communication is discussed and demonstrated based on the normal mode simulations and at-sea experiments.