浅海中低频水声信道仿真研究

Low-mid frequency random underwater channel simulation in shallow water environment

在中低频段(通常为数百至数千赫兹频率范围),传播损失、时空相关性以及时空平稳性等水声信道特性是主、被动目标探测和远程通讯技术研究的重点。为了模拟信道的时空去相关特性,应用KrakenC传播模型得到理想信道传递函数H(r,ω),并在此基础上,提出了新的基于信道时延的相位加扰方法。通过数值仿真,该方法可以很好地在统计特性上模拟海试LoFAR’08中的实际浅海信道测量数据。测量数据由拖曳式电火花声源(有效带宽为300Hz^2.5kHz)激励浅水信道得到。

In the Low-mid frequency band（Typically,several hundred hertz to several kilohertz）,the main underwater channel features are important to the active/passive target detection and long-range communication problems,such as the transmission loss,temporal-spatial coherence and nonstationarity.In order to simulate the channel spa-tial-decorrelation characteristics,a new delay-dependence perturbation method is provided to modify the ideal channel transfer function H（r,ω）,which is obtained through the KrakenC acoustic-field calculation model.The numerical simulation results of the macro-parameter channel model conform well to the real shallow water channel measurements with towed electric-discharge sources（Effective bandwidth： 300Hz-2.5kHz） in the sense of statistical characteristics.