Space-Time Spectrum Completion SR-STAP Method for Non-Uniform Clutter Suppression

Sea clutter suppression is an important part of ground moving target indication (GMTI). The independently and identically distributed (IID) property between samples is disrupted by the non-stationarity of clutter due to the bistatic radar and the non-uniformity caused by the sea motion, resulting in worse clutter suppression results. While the direct data-domain space-time adaptive processing (D3-STAP) method based on sparse recovery (SR) can recover space-time spectrum directly by using cell under test (CUT), the space-time spectrum cannot be recovered completely. To overcome the problem of missing space-time spectrum caused by one single sample, a space-time spectrum completion SR-STAP(STSC-SR-STAP) method based on clutter ridge is proposed. In the proposed method, the clutter ridge structure is calculated at first using prior information. Then, the atom set corresponding to the clutter ridge is extracted using the clutter ridge structure, and the Hankel matrix transformation is performed on the atom set with missing values. The matrix completion method is then applied to complete the missing values in amplitude, thereby solving the problem of missing clutter space-time spectrum. Simulation results show that the proposed algorithm can effectively complete the space-time spectrum and improve clutter suppression performance.