MIMO-SAR solution based on azimuth phase coding waveforms and digital beamforming

In multiple-input multiple-output synthetic aperture radar (MIMO-SAR), it is necessary to separate the radar echoes corresponding to each transmit waveform. However, most existing waveforms cannot be reliably separated from the received radar echoes, thereby degrading the performance of MIMO-SAR. As a solution to this problem, a novel class of waveform design based on azimuth phase coding (APC) and digital beamforming (DBF) is proposed in this paper. Because of the APC shift effect in the Doppler domain, the overlapped echoes corresponding to different proposed APC waveforms arrive from different azimuth angles and, thereby, are well separable by azimuth DBF. Simulation results using both point target and distributed scene validate the feasibility and effectiveness of the proposed MIMO-SAR Solution.