An Enhanced Knowledge-Aided Clutter Compensation Method for Real-Time Processing in Spaceborne Bistatic Radar Systems

Abstract

Due to the nonideal and asymmetric radar configuration, the clutter echoes in spaceborne multistatic radar systems often exhibit strong range dependence. This phenomenon can significantly reduce the estimation accuracy of the clutter covariance matrix (CCM), thereby degrading the clutter suppression performance and weakening the radar system’s capability in detecting slow-moving targets. To address this issue while satisfying the real-time processing requirements, this article proposes an enhanced knowledge-aided clutter compensation (KAC+) method for real-time processing in spaceborne bistatic radar systems. In the proposed approach, the clutter energy distribution is first approximated as a bistatic antenna pattern. By means of analytical computation, the coordinates of the clutter centroids at different range gates are iteratively calculated, and the corresponding spatial and Doppler frequencies are further derived. Based on this, a 2-D space–time compensation matrix is constructed to correct the range-dependent clutter. Finally, a set of semirealistic simulation experiments and complexity analysis are conducted to validate the effectiveness and computational efficiency of the proposed clutter compensation method.