基于白噪声加载近似的子空间相交方位估计方法

Subspace Intersection Method for Bearing Estimation Based on White Noise Loading Approach

利用长线阵在水下多途声传播环境下估计源方位,子空间相交(Subspace intersection,SI)方法有很好的估计性能,本文旨在改善其稳定性。在分析得出SI稳定性差的原因是简正波阵列响应矩阵(Array response ma-trix,ARM)不满秩的基础上,本文提出在ARM上加载白噪声(White noise loading approach of SI,WASI)来改善SI的稳定性,给出了自适应确定白噪声加载参数的方法,并设计假想实验考察了白噪声加载对WASI的影响。数值仿真结果表明,WASI很好地改善了SI的稳定性,对弱目标检测和源方位估计性能和SI接近相同。

Subspace intersection （SI） method is investigated to improve its stability. The method has good bearing estimation performance with long line array in multi-path environ- ment of underwater sound propagation. This paper analyzes SI stability and points out that not full-ranked array response matrix（ARM） is responsible for SI poor stability. Then, the white noise loading approach of SI （WASI） is presented to improve SI stability, the method for calculating parameters of white noise adaptively loading is given, and the effect of white noise loading on WASI is examined using a specially designed imaginary experiment. Numerical simulation results indicate that WASI improves SI stability and has nearly same performance for SI in weak source detection and bearing estimation.