基于多途信道的舰船辐射噪声功率谱密度估计*

针对低信噪比下利用单水听器估计辐射噪声功率谱密度精度较差的问题,提出一种基于多途信道传输函数估计的垂直阵测量估计1 m处舰船辐射噪声功率谱密度的方法。该方法将信道传输函数表示为多途路径近场阵列流形向量的叠加,较快地估计了信道传输函数,将其用于舰船辐射噪声功率谱密度估计,可较简便地估计距声中心1 m处辐射噪声的功率谱密度,即谱源级。分析了产生功率谱密度估计误差的原因,包括信道估计误差和环境噪声引起的误差,为降低估计误差提供了理论依据。仿真结果表明,该方法估计1 m处辐射噪声功率谱密度的性能良好。

Power spectral density estimation of ship-radiated noise based on multipath channel

A power spectral density (PSD) estimation method based on the multipath channel estimation with a vertical linear array (VLA) for ship-radiated noise at 1 meter is proposed to solve the poor accuracy of the PSD estimated by a single hydrophone at the low signal-to-noise ratio (SNR). In this method, the channel transfer function is approximated by the superposition of the near-field array manifold vectors of different paths for convenience, which can be used to estimate the PSD of ship-radiated noise at a distance of 1 meter from the sound center. The reasons for PSD estimation error, including the estimated channel error and the ambient noise, are analyzed, which provides a theoretical basis for reducing estimation error. The numerical results show that the proposed method can estimate the PSD of the radiated noise at 1 meter well.