时变强多途干扰下基于差分编码的水声OFDM通信算法

Underwater acoustic OFDM communication algorithm based on differential coding under time-varying strong multi-path interference

时变强多途干扰影响水声通信系统性能,针对时变强多途干扰问题,提出基于差分编码的水声OFDM通信(Underwater acoustic OFDM communications based on differential coding,DC-OFDM)算法。利用循环前缀技术和OFDM通信技术固有的抗多途特性,有效消除时变多途干扰,避免信道估计环节,直接进行解码判决。南海实测信道仿真(信噪比为8dB时,DQPSK100组仿真试验,2×10^(6)个源码,全部正确解码)和水箱试验(信噪比为15dB时,DQPSK100组水箱试验,2×10^(6)个源码,在时变强多途干扰下全部正确解码)。结果表明,所提算法能有效解决时变强多途干扰问题,实现时变强多途水声信道下的可靠水声通信。

The performance of underwater acoustic communication system is affected by time-varying strong multipath interference.Aiming at time-varying strong multi-path interference,an underwater acoustic OFDM communications algorithm based on differential coding is proposed.By using the inherent multi-path resistance of cyclic prefix technology and OFDM communication technology,time-varying multi-path interference can be effectively eliminated,channel estimation can be avoided,and decoding decision can be made directly.The results of south China sea channel simulations(the experiment conditions are:SNR is 8 dB,the number of simulation is 100,the number of the source codes is 2×10^(6),all codes were decoded correctly)and water tank experiments(the experiment conditions are:SNR is 15 dB,the number of experiment is 100,the number of the source codes is 2×10^(6),all codes were decoded correctly under the time-varying strong multi-path interference)are provided to demonstrate that the proposed algorithm can effectively solve the problem of time-varying strong multi-path interference,realize reliable underwater acoustic communication under time-varying strong multi-path channel.