【摘要】 湍流边界层压力起伏导致拖曳阵列流噪声难以精确建模与抑制,为此分析了拖曳阵列流噪声的产生机理与统计特性。针对非高斯分布的拖曳阵列流噪声,发展了混合高斯模型建模方法,同时建立了多通道的拖曳阵列中声源信号的低秩模型,并对流噪声和声源信号模型中的参数通过期望最大算法进行求解,最终实现了水听器接收信号中的流噪声与声源信号成分分离。对实际湖试数据进行流噪声抑制与目标方位估计,结果表明,在不影响定位结果的前提下,最大旁瓣级抑制达到8～10 dB。更多还原

【Abstract】 Aiming at the problem that it is difficult to accurately model and suppress the towed array flow noise caused by the pressure fluctuation in the turbulent boundary layer, this paper analyzes the generation mechanism of the towed array flow noise and the statistical properties of the noise. A hybrid Gaussian model modelling method is developed for the non-Gaussian distributed towed array flow noise, and a low-rank model of the acoustic source signal in the multi-channel towed array is established. The parameters in the model of the flow noise and the acoustic source signal are solved by the expectation-maximization algorithm,which ultimately realizes the separation of the flow noise and acoustic source signal in the received signal of the hydrophone. The results of the flow noise suppression and target orientation estimation of the actual lake test data show that the maximum side-valve level suppression reaches 8-10 dB without affecting the localization results.更多还原