基于协方差矩阵加权的非理想情况下自适应阵列干扰自由度估计

On Estimate of Interference Degrees of Freedom of Adaptive Array in Non-Ideal Scenarios Based on Covariance Matrix Tapers

在均匀线阵条件下,证明了干扰特征值渐近为周期延拓后的干扰空间谱这一性质.据此提出了一种非理想情况下估计干扰自由度,即大干扰特征值个数的方法.该方法首先利用协方差矩阵加权得到非理想情况下的干扰协方差函数和对应的空间谱,然后根据周期延拓后的干扰空间谱估计干扰自由度.仿真结果验证了该方法的有效性.

In the case of uniform linear array （ULA） system, it is found that the interference eigenvalue asymptotes to the periodically extended version of the interference spatial spectrum. This fact was then employed in estimation on the number of interference degrees of freedom （DoF）, i. e., the number of significant interference eigenvalues, in the presence of various non-ideal effects. The proposed method first employs covariance matrix tapers to obtain the interference covariance function and its corresponding spatial spectrum in non-ideal scenarios. Then the number of interference DoF is estimated according to the periodically extended spectrum. The simulations agree with the estimation results.