针对传统波达方向(Direction of arrival,DOA)估计算法在小快拍数、低信噪比以及信源信号相干等条件下估计精度低等问题,提出一种基于迂回式匹配追踪算法的DOA估计方法.通过对空间按照潜在的入射角等角度进行划分,构造超完备冗余字典,...针对传统波达方向(Direction of arrival,DOA)估计算法在小快拍数、低信噪比以及信源信号相干等条件下估计精度低等问题,提出一种基于迂回式匹配追踪算法的DOA估计方法.通过对空间按照潜在的入射角等角度进行划分,构造超完备冗余字典,采用迂回式匹配追踪算法对稀疏信号进行重构,得到信号中的非零元素按位置编号转化成对应的方向角度,即正确的DOA估计值.仿真结果表明:基于迂回式匹配追踪算法的DOA估计算法在单快拍情况下仍能得到有效估计值,在强噪声环境中也具有较好的稳健性.展开更多
In this work,acoustic vector characteristics of near fields scattered by an underwater finite cylindrical baffle are investigated theoretically and experimentally.The analytic expressions for the scattered pressure an...In this work,acoustic vector characteristics of near fields scattered by an underwater finite cylindrical baffle are investigated theoretically and experimentally.The analytic expressions for the scattered pressure and particle velocity are derived using the elastic thin shell theory.Calculations are presented for the scattered near fields of the pressure,the particle velocity and the intensity.It is found that the pressure and the particle velocity fields near the surface of the cylindrical baffle are characterized by complex interference structure,particle velocity directions and the source bearings are not consistent.The phase difference between the pressure and the particle velocity is not zero and the intensity vector does not reflect the sound bearings.It can be noted that the distortions of the fields will make the original vector signal processing method based on the free space assumption be no longer applicable in the presence of the cylindrical baffle.These results can serve as a basis of the application for the acoustic vector sensor on board.展开更多
文摘针对传统波达方向(Direction of arrival,DOA)估计算法在小快拍数、低信噪比以及信源信号相干等条件下估计精度低等问题,提出一种基于迂回式匹配追踪算法的DOA估计方法.通过对空间按照潜在的入射角等角度进行划分,构造超完备冗余字典,采用迂回式匹配追踪算法对稀疏信号进行重构,得到信号中的非零元素按位置编号转化成对应的方向角度,即正确的DOA估计值.仿真结果表明:基于迂回式匹配追踪算法的DOA估计算法在单快拍情况下仍能得到有效估计值,在强噪声环境中也具有较好的稳健性.
基金supported by the Special Foundation for the State Major Basic Research Program of China (Grant No. 40827003)
文摘In this work,acoustic vector characteristics of near fields scattered by an underwater finite cylindrical baffle are investigated theoretically and experimentally.The analytic expressions for the scattered pressure and particle velocity are derived using the elastic thin shell theory.Calculations are presented for the scattered near fields of the pressure,the particle velocity and the intensity.It is found that the pressure and the particle velocity fields near the surface of the cylindrical baffle are characterized by complex interference structure,particle velocity directions and the source bearings are not consistent.The phase difference between the pressure and the particle velocity is not zero and the intensity vector does not reflect the sound bearings.It can be noted that the distortions of the fields will make the original vector signal processing method based on the free space assumption be no longer applicable in the presence of the cylindrical baffle.These results can serve as a basis of the application for the acoustic vector sensor on board.
