MIMO-SAR waveforms separation based on virtual polarization filter

The unwanted coupling exists inevitably among multiple orthogonal waveforms in a same frequency area for multiple-input and multiple-output synthetic aperture radar (MIMO-SAR). In this paper, a new polarized MIMO-SAR model is established with two transmitting antennas and multiple receiving antennas at first. Then, a virtual polarization filter (VPF) is proposed to separate superposed returns caused by multiple transmitted waveforms based on detection on the polarized parameters via particle swarm optimizer (PSO). Compared with the conventional matched filter to separate the orthogonal waveforms, it is shown that the coupling noises can be significantly suppressed by the proposed VPF-based method and the orthogonality is not necessary among different transmitting waveforms. Finally, experimental data experiments are also provided to demonstrate the effectiveness of the proposed method.