A Novel Clutter Spectrum Compensation Method in a Spaceborne BISTATIC Early Warning Radar System

For a spaceborne bistatic early warning radar system with severe range dependence, the multi-channel division of the large-aperture antenna will bring about spatial under-sampling, which can lead to the spatial spectrum center estimation error and greatly influence the bistatic radar clutter suppression performance. To solve this problem, a novel bistatic clutter spectrum compensation method based on FFT range fitting is proposed in this paper. In the proposed method, the clutter Doppler and angle centers in different range gates are firstly estimated through Eigen decomposition. Then, the pseudo-single frequency complex sequence corresponding to the estimated spatial clutter center sequence is constructed, and the slope related to the angle centers is estimated after performing the FFT. Finally, the compensation matrix is constructed, so as to achieve the clutter non-stationary error compensation. The effectiveness of the proposed method is validated by the simulation experimental results.