Compressive sensing-based ground moving target indication for dual-channel synthetic aperture radar

Multi-channel synthetic aperture radar (SAR) system has excellent performance of main-lobe clutter suppression. However, the resulting enormous amount of sampling raw data increases storage and transmission load. To alleviate such payloads, the authors propose a SAR/ground moving target indication (GMTI) method using compressive sensing (CS) with a very limited number of echo samples, based on the fact that the moving targets are usually sparse although clutter scattering centres are non-sparse in most cases. In the proposed method, dual channel SAR data are sampled sparsely in the azimuth direction and jointly processed. Firstly, a transform matrix is constructed to separate the energy support areas of moving targets from that of all scattering centres. Then, the authors can roughly obtain the energy support areas of all scattering centres via CS. Finally, based on the acquired energy support areas above, GMTI is achieved by solving a weighted l₁ optimisation problem. Simulated and real data experiments demonstrate that the proposed method performs well with reduced sampled raw data, even if clutter scattering centres have a low-sparse level.