Robust Distributed Array Radar Adaptive Interference Suppression Method for Large-scale Steering Mismatch due to Inter-array Errors

Adaptive beamforming of distributed array radar (DAR) can suppress most of the interference because of the narrow main-lobe. However, DAR requires a more sophisticated error calibration process to ensure processing performance. Current techniques are not yet able to fully calibrate the errors caused by inter-array time, frequency, or phase asynchrony. To address the problem of adaptive interference suppression when the array steering vector (SV) is mismatched at large scale, we proposed a new adaptive interference cancellation method which is derived from the covariance decomposition of joint adaptive beamforming. Using the decomposition-derived weighted accumulation of different channels, we achieve the inter-ference suppression capability comparable to the joint adaptive approach, which is not possible with the conventional interference cancellation methods. In addition, the method can maintain robust performance under large-scale SV mismatch because it is independent of inter-array SV. The proposed method is simple and effective, as will be validated via simulations.