M元仿海豚叫声隐蔽水声通信

M-ray covert underwater acoustic communication by mimicking dolphin sounds

针对水下通信隐蔽性需求,提出利用海洋中固有的海豚叫声实现隐蔽水声通信的方法。基于仿生学原理,将真实或模拟的海豚叫声信号应用于水声通信中,允许信号被检测,但在识别过程中被排除以达到隐蔽水声通信的效果。采用相关性良好的海豚嘀嗒声信号构成信号码样本库,信息调制在不同嘀嗒声信号的时延差上,采用M元技术提高通信速率,RAKE接收机技术实现仿生通信体制中的信道均衡。在湖试实验中,水平通信距离3 km,通信速率69 bit/s,误码率小于10-4,结果证实了该方法的有效性和可行性。

In order to meet the requirements of covert underwater acoustic communications, a bionic camouflage scheme has been proposed using the mimicry or intrinsic dolphin sounds. The idea here is to design a modulation waveform which appears to be naturally occurring in the underwater acoustic environment. It is allowed to be detected, but an adversary could easily exclude it in the process of recognition! classification. The signal emitted by dolphin sounds adopted has good properties of auto-correlation or cross-correlation, the information is modulated between different clicks. The M -ray technique is used to improve the communication rate; equalization is realized through the RAKE receiver. The simulation and lake trial show that the proposed scheme can work efficiently. A data rate of 69 bit/s with a bit error rate （BER） of less than 1O-4was acquired at a distance of 3 km during the lake trial.