主源实时高分辨幂法测向系统及其性能研究

Power Method Based Real-time High Resolution Direction Finding Scheme for Principal Sources and Its Performance Investigation

在声场及电磁场中，经常要求在非均匀噪声场及目标相对方位迅速变化的情况下，快速精确地估计出主源方位．而在这种情况下传统的方位估计方法往往难以在工科中应用．文中为此提供幂法方位估计方法，详细研究了诸如背景噪声的统计特性、背景噪声场的空间相关性、传感器阵的随机扰动及基阵安装的几何误差等实际问题对益法方位的估计性能及其迭代过程收敛速度的影响，并给出了相应的典型曲线．硬件实验表明：幂法方位估计方法对接收传感器阵元间噪声特性不敏感，即使采用很短的输入数据段也具有良好的精度、稳健性与快速收效能力．它特别适用于目标相对方位变化很快、稳定输入数据段很短、背景噪声场非白等情况下的主源方位实时精确估计与跟踪，非常易于工程实现．

In acoustic and electromagnetic applications, there exist extensiverequirements of fast and high resolution direction finding of the principal sourceswhose orientation related to observing sensors changes swiftly in nonwhite noisefields, while the conventional direction finding methods can hardly keep valid tosuch situations. A rapid high- resolution direction finding scheme is presented forprincipal sources with applications to acoustic fields with nonwhite noise. Itsinfrastructure is hased on the power method iteration. A series of practicalproblems were investigated in detail and typical statistic curves and tables weregiven, such as the effects of the ambient noise statistics, the spatial correlation ofthe ambient noise field, the geometrical error of the sensor array, and randomswinging of the sensor array on the direction finding accuracy and on theconvergence rate of the iterative process and its accelaration, etc. Experimentsdemonstrate that it keeps high resolution, robustness and rapid convergence evenwith very short stationary inputs in a nonwhite noise field together with a slowlyrandom swinging sensor array even with some geometrical distortions. It is provedeasy to be implemented in engineering, particularly for high-resolution directionfinding and tracking of the principal sources with short time stationary data innonwhite noise fields.