基于幅度补偿的MVDR水下噪声源近场定位识别方法研究

Underwater noise sources identification in near-field locating based on MVDR method with amplitude compensation

降低舰船噪声,首先要找到其主要噪声源,然后采取有针对性的减振降噪措施。针对现有基于近场聚焦波束形成等噪声源近场定位方法的不足,介绍了基于幅度补偿的MVDR(minimum variance distortionless response)近场聚焦波束形成噪声源近场定位识别方法。该方法在MVDR算法的基础上引入幅度补偿,可以有效估计噪声源的相对强度;可以提高基阵在低频段的空间分辨率,在高频段能进一步抑制空间混叠;同时还可以进一步抑制背景噪声,因此该方法能够给出系统噪声源的空间位置分布及能量分布,从而准确找到系统中主要噪声源,采取有针对性的减振降噪措施。计算机仿真及湖试实验数据处理结果验证了该方法的有效性,具有一定的工程应用价值。

To reduce ship noise,first of all it should be done to find the main noise source,then appropriate measures for vibration and noise reduction were adopted.Aiming at shortcomings of the existing methods for under-water noise sources recognition in near-field positioning,a new method for underwater noise source identification in near-field location based on MVDR with amplitude compensation was proposed.This method introduced the rate of compensation based on MVD algorithm;it greatly enhanced the spatial resolution rate at lower frequencies of the base array;it effectively suppressed the spatial aliasing at higher frequencies;and it reduced the side lobe level at the same time,the background noise was further suppressed;and the relative intensity of the noise sources was described.Then,high-resolution near-field underwater noise source locating and identification were achieved.Some simulations for single-frequency line spectrum and boradband signals were done.Both simulations and tests proved that the peoposed method is effective and applicable in engineering.