Performance Analysis of the Robust Adaptive Beamforming Based on Worst-Case Performance Optimization

The performance of adaptive beamforming degrades dramatically in practice due to steering vector mismatches.As a solution,diagonal loading is usually used to improve its robustness.However,how to select the loading level remains an open problem.In this paper,the robust adaptive beamforming(RABF) which determines the loading level based on worst-case performance optimization is investigated and a simple closed-form solution to the optimal loading is derived after some approximations,revealing how different factors affect the optimal loading.On the basis of this solution,a performance analysis is carried out,focusing mainly on the source power estimation and signal-to-interference-plus-noise ratio(SINR).The corresponding analytical results are presented for performance prediction.Finally,numerical examples demonstrate the correctness of the analysis in this paper.