广义信号子空间拟合角度-极化联合估计

Joint Angle-Polarization Estimation via Generalized Signal-Subspace Fitting

针对相干信号波达方向(DOA)和极化参数的同时估计问题,提出了适用于任意结构极化敏感阵列和完全/部分极化信号源的广义信号子空间拟合方法.该方法利用空间相位矩阵和信号极化矢量之间的线性关系,借助信号子空间旋转矩阵的适当分离实现了角度和极化参数的解耦,使得DOA估计和极化参数估计可分别通过唯角度和唯极化搜索获得.与传统子阵平滑信号解相干方法不同,广义信号子空间拟合方法对阵列结构无特殊要求,且不存在孔径损失问题.仿真结果表明,广义信号子空间拟合方法在低信噪比和短快拍数条件下性能均要优于空间平滑和极化平滑两种传统方法.

The signal subspace fitting technique is extended to a general polarization sensitive array for direction-of-arrival（DOA） and polarization estimation of coherent signals.Based on the linear relation between the spatial phase matrix and polarization vector,the new method enables uncouple DOA and polarization estimation via an appropriate separation of signal-subspace rotation matrix.Unlike spatial smoothing and polarimetric smoothing,this generalized signal subspace fitting method（GSSF） does not require a certain number of matched subarrays and can be implemented without aperture reduction.It is shown that GSSF is superior to both the spatial smoothing and polarimetric smoothing preprocessed methods in terms of DOA estimation accuracy,especially in the presence of low signal-to-noise ratio values and short data samples.