基于投影方法的稳健波束形成算法能够用于改善一般导向矢量失配的稳健性,而且相比于其他算法实现简单。通过分析,在信号加干扰子空间准确已知的条件下,该方法与基于特征子空间的稳健算法等价。由于该方法适用于较高信噪比和较低信号加干扰子空间维数的场景,而且子空间及其维数必须是已知的,因此给出了一种用于信号加干扰子空间及其维数的稳健估计方法,使该算法的应用条件得以满足。详细分析了理想条件下子空间选取对算法性能的影响,并进行了详细的仿真分析,验证了所提出方法的正确性和有效性。
The projection method-based beamformer is known to provide an improved robustness against more general types of steering vector mismatches and is more simple than other methods in the implementation.When the signal-plus-interference subspace is obtained exactly,this algorithm is equivalent to the eigen-subspace-based beamformer.Since this approach is applicable for the scenario with the higher signal-to-noise ratio and the lower dimension of the signal-plus-interference subspace.Additionally,the dimension must be known in the latter processing.A robust method is proposed to estimate the subspace and its dimension,therefore,its application condition can be met.The impact of the subspace selection on its performance under the ideal condition is analyzed particularly,and the simulation attests its correctness and effectiveness.