基于时变调制的舰船噪声信号仿真算法研究

为了向被动声纳提供逼真的舰船噪声信号,分别采用基准谱级和谱状、线谱的频率和幅度及相位、轴频和叶频来表征舰船噪声信号中的连续谱、线谱、时变调制谱,同时给出了一套高逼真度、高效率的可控特性噪声实时仿真算法:经由自相关函数、AR系数各自的解算和自回归滤波进行平稳连续谱噪声的求解;通过线谱系列频率、幅度和相位的解算,再以系列正弦波和的形式实现线谱;采用连续谱噪声自回归计算、起伏脉冲串时间调制函数构造和连续谱噪声信号调制三步法给出时变调制谱。上述算法已在以TS101为处理器的DSP运算平台上得以实现,已成功地应用于多种声纳仿真测试。

Research on Simulation Algorithm of Vessels Noise Signal Based on Time-varying Modulating

In order to provide the lifelike vessels noise signal for passive sonar,the noise continuous spectrum was characterized by benchmark spectral class and spectrum-shaped table,the noise line spectrum was characterized by line spectrum frequency,amplitude and phase,the noise time-varying modulating spectrum was characterized by shaft frequency and blade frequency.And a realistic,high efficiency and controllable simulation algorithms were given.The real-time simulation of stationary continuous spectrum noise was achieved though autocorrelation function,AR coefficient and autoregressive filter.The real-time simulation of line spectrum was achieved in the form of sum of a series of sine wave through calculation of amplitude,frequency and phase of line spectrum.The real-time simulation of time-varying modulating spectrum was achieved through autoregressive algorithm of stationary continuous spectrum,time-varying modulating function of fluctuation pulse train and the modulation of noise continuous spectrum.The algorithms have been implemented on the DSP platform with TS101 processor and successfully applied in a variety of sonar test equipment and sonar simulation system.