Concept design of a MIMO-SAR using frequency diversity

A MIMO-SAR framework based on frequency diversity is presented. The variety of carrier frequency causes the phase modulation and the change of FM rate in azimuth. They will bring spurious responses in the final radar imaging. The influence of phase modulation is overcome by selecting an appropriate sampling rate to the range signal. When the range cell migration can be neglected, we can assume the azimuth signal as the result of a multi-channel sampling system, and then the influence of FM rate changing is eliminated by Doppler spectrum reconstruction. The feasibility of the imaging algorithm is validated by simulation experiments.