基于频移键控的仿海豚哨声水声通信技术

Bionic Underwater Acoustic Communication by Mimicking Dolphin Whistle Based on Frequency Shift Keying

针对水下隐蔽声通信的需求,该文提出一种基于频移键控的仿海豚哨声水声通信方法,通过模拟海豚哨声以降低通信信号被发现的概率,从而实现水下隐蔽声通信。该方法将信息调制生成的基带信号以一定比例与海豚哨声信号时频谱轮廓曲线相加获得合成哨声时频谱,再生成合成哨声作为仿生通信信号。接收端提取接收到的合成哨声与本地生成的存在固定频差的海豚哨声相干相乘,经过低通滤波获得频移键控信号进行信息解调,实现仿生通信。通过时频相关系数和Mel倒谱距离分析了通信信号仿生效果。仿真与海试试验验证了该方法的可行性,当码元宽度为0.1s时可在2km距离上实现有效通信,且时频相关系数不低于0.99。该方法调制解调原理简单,系统资源消耗更少,更易于工程实现,为仿生水声通信算法的实际应用提供技术支撑。

To meet the demand of covert Underwater Acoustic Communication(UAC),a bionic UAC method by mimicking dolphin whistle based on Frequency Shift Keying(FSK)is proposed.The information modulated baseband signal is added to the selected spectrum contour of the dolphin whistle with a certain weight to obtain the synthetic contour.Then generate the synthetic whistle to transmit the information.The receiver extracts the received synthetic whistle,and coherently multiples it with the local whistle,whose contour has a fix frequency difference from the selected whistle contour.A low-pass filtering is adopted to obtain the FSK signal,which is used for demodulation.The bionic effect is analyzed through Time-Frequency Correlation Coefficient(TFCC)and Mel frequency cepstrum Distance(MelD).Simulation and sea trial verified its feasibility.A reliable communication can be achieved at 2km when the symbol width is 0.1s and the TFCC is over 0.99.The low complexity makes the proposed bionic UAC method more suitable for implement,which provides technical support for the practical application of bionic UAC.