Robust Beamforming Technologies for Conformal Array of Small-Scale Platform Based on Covariance Matrix Fitting

To achieve robust detection on small-scale platforms like unmanned undersea vehicles(UUVs), which are characterized by their limited maneuverability and array apertures, various beamforming algorithms were designed by leveraging U-shaped conformal planar arrays specifically tailored for small-scale platforms. The impact of factors such as snapshot rate, input signal-to-noise ratio, and steering vector errors on the robustness of these beamforming technologies was analyzed. Although the minimum variance distortionless response(MVDR) method is noted for its superior array gain, its performance significantly deteriorates in the presence of steering vector errors and inaccuracies in the covariance matrix estimation. To mitigate these issues, the covariance matrix fitting-based beamforming method and the dual-constraint robust MVDR method were introduced. The robustness of the robust beamforming methods applied in conformal arrays of underwater small-scale platforms was validated through numerical simulations and comparison with various beamforming technologies. Finally, the actual performance of various beamforming technologies was further compared and verified by anechoic pool experiments with the array element position error considered.