Diagonal Loading Method with Small Snapshot Number and Steering Vector Errors

Diagonal loading is often used to improve the robustness of beamforming algorithms as a classic method. In this paper, two classic diagonal loading algorithms are first discussed respectively for the case of small number of snapshots and for the case of steering vector errors, and then they are combined to improve the performance of the original algorithms, and the formulas for the joint algorithm are given. Computer simulation results show that the joint method can expand the applicability of the two algorithms at the steering vector error level, so that the signal-to-interference-noise ratio of the array output maintains good performance within a larger range of standard deviations of the steering vector. Secondly, the combined method can compensate for the limitation of the small range of scale factor values in the steering vector errors variance loading method, reduce the possibility of adverse consequences caused by improper scale factor values, and improve the robustness of the algorithm.