Robust broadband adaptive beamforming for planar arrays with tunable nulls in high-dynamic scenario

Traditional space-time adaptive processing (STAP) is extensively adopted in various fields such as navigation satellite, sonar, radar, etc. It can form the sharp null in the angle domain (azimuth and elevation) to suppress interferences. However, the null cannot continuously match the interference in dynamic interference scenarios. To address the problem, a STAP strategy based on Simpson-statistical constraint for the planar array is proposed, capable of generating wide nulls with flexible width and asymmetry. Firstly, a taper matrix (TM) is calculated, which can achieve asymmetric widening of the null in the angular domain. Asymmetry is achieved by introducing an artificial interference group that satisfies the Simpson-statistical constraint. Then, the eigen-covariance matrix (ECM) is obtained by the eigen-decomposition of the sample covariance matrix (CM). The unequal null width is generated by reconstructing the array CM of the planar array based on the TM and ECM. Finally, the computation of weight is carried out using a linear phase undistorted beamformer. Extensive testing demonstrates the robustness of the proposed solution.