Spatial Multi-Interference Suppression Based on Joint Adaptive Weight for Distributed Array Radar

Distributed array radar is widely applied to suppress the mainlobe interference due to the large equivalent aperture with auxiliary array. In general, the distributed array radar only can suppress a certain number of interferences because of limited auxiliary unit radars. When there exist multi interferences, especially massive sidelobe interferences, the performance of the mainlobe interference suppression degrades severely. To solve this problem, the auxiliary unit radars adopt phased array system and a spatial multi-interference suppression method based on joint adaptive weight for distributed array radar is proposed in this paper. In proposed method, the interference-plus-noise covariance matrix of each radar is firstly reconstructed based on Capon spectral estimator to remove the mainlobe interference. Subsequently, the internal adaptive weight is calculated based on the reconstructed matrix to suppress sidelobe interferences. Then, the external adaptive weight is calculated based on the data processed by internal adaptive weight to suppress the mainlobe interference. Finally, the joint adaptive weight is calculated based on the internal weight and the external weight, and the output of adaptive beamforming is obtained. The effectiveness of the proposed method is verified by numerical simulations.