提高卫星导航性能的阵列参数估计算法

针对卫星导航信号参数估计性能严重影响导航定位精度，提出了一种利用电磁偶极子对提高信号波达方向和极化参数估计性能的方法。充分利用接收数据协方差矩阵，通过两次特征分解，由特征分解的特征值进行极化参数估计。利用小圆环子阵导向矢量得到波达方向的粗略而无模糊的估计，大圆环子阵导向矢量得到有模糊的估计，通过解模糊得到精确的无模糊的估计，从而大幅提高了到达角的估计精度。比较了单个圆环阵列和同心圆环阵列的参数估计性能，分析了参数估计精度对抗干扰性能的影响，仿真结果表明参数估计精度的提高有效改善了卫星导航抗干扰的性能。

A Parameter Estimation Algorithm for Improving Performance of Satellite Navigation

 In order to improve the accuracy of satellite navigation and positioning, a joint estimation method for direction of arrival (DOA) and polarization parameters using dipole pairs is proposed in this paper. The signal subspace is obtained by decoupling the data covariance matrix. The polarization-space matrix is formed according to the signal subspace and the special structure of dipole pair array. The polarization parameters and the steering vectors of the whole array are acquired respectively from the eigenvalues and the corresponding eigenvectors of the polarization-space matrix. The steering vectors of small circle sub-array are used to give unambiguous but high variance estimates of DOA, they are used as coarse references to disambiguate the cyclic phase ambiguities in the steering vectors of big circle sub-array when the radius exceeds a half-wavelength. The parameter estimate performance of a single circle array and a concentric circular array is compared. The effect of parameter estimation accuracy on the anti-jamming performance of satellite navigation system is also simulated. Simulation results verify the effectiveness of the proposed algorithm.