舰船宽带连续谱噪声的模拟

Simulation of broadband ship noise with continuous spectrum

首先对舰船辐射噪声信号的时域特性和频域特性进行了分析讨论,根据噪声的连续谱特性,提出了一种用FIR滤波器实现宽带噪声信号模拟的方法。由于舰船宽带信号的连续谱在高频段具有-6dB/oct的衰减特性,因此该FIR滤波器的幅频响应也要与此一致,且为线性相位,即该滤波器的频率响应要具有特定的形状。采用了自适应方法很方便地实现了该特定频率响应FIR滤波器的设计,再将高斯白噪声信号通过该滤波器即实现宽带噪声信号的模拟。仿真结果表明,该方法较真实地模拟出任意给定频域特征的宽带连续谱噪声信号。

The time-domain and frequency-domain features of ship radiation noise are analyzed.According to the frequency-domain feature of the noise with continuous spectrum, simulation of the broadband noise with white noise and an FIR filter is presented. Base on the theory of linear systems, the FIR filter should possess a specific frequency response to match the required spectrum of ship radiation. A special frequency response FIR is designed using an adaptive method. The ship＇s broadband continuous was obtained using such a simulation system, showing that the method is effective.