船舶辐射噪声解调谱相位耦合特性与应用

Phase-coupling characteristics of ship radiated-noise demodulation spectrum and application

研究了船舶辐射噪声解调谱谐波线谱的相位特性,通过对实际船舶辐射噪声数据分析,指出船舶辐射噪声解调谱线谱中轴频线谱相位和部分谐波线谱相位之和,与叶频线谱相位的差值为零或为一常数,即存在相位耦合关系。给出了频率具有耦合关系、相位差为非零常数谐波信号的高阶累量,并对这种谐波信号的高阶谱进行了仿真计算。研究了船舶辐射噪声解调谱线谱相位耦合特性的利用方法,通过对部分典型弱调制噪声信号高阶谱分析,指出利用相位耦合关系可以提高弱解调谱船舶目标的螺旋桨参数特征提取能力。

Phase characteristics of ship radiated-noise demodulation spectrum harmonic components are considered. By analyzing a large number of ship radiated noise data, it is found that the sum phase of line spectrum at shaft frequency and its some harmonic subtracts the phase of blade frequency line spectrum is zero or other constant in the demodulation spectrum, which is called phase coupling. Higherdorder cumulant of the harmonic signal with phase coupling relationship is given, and higher-order spectrum of the harmonic signal is simulated. The application of phase coupling relationship is studied. According to the higher-order spectral analysis of some weak modulated ship radiated noise, it is indicated that using the phase coupling relationship can improve the ability to extract propeller parameter, especially for weak modulated ship radiated noise.