Joint space-time-frequency method based on fractional fourier transform to estimate moving target parameters for multistatic synthetic aperture radar

In practice, the configuration of spaceborne multistatic synthetic aperture radar (MSAR) is generally three-dimensional (3D) stereo geometry, under which condition most current algorithms of motion parameter estimation are invalid. In this study, a joint space-time-frequency method is presented to estimate motion parameters of ground moving target for MSAR of 3D geometry. First, the array expression for azimuth echo named extended space-time model (ESTM) is derived; then on the basis of ESTM, a spatial time-frequency distribution method based on fractional Fourier transform algorithm is derived; finally the performance of the presented method is analysed, and the advantages comparing with velocity synthetic aperture radar are discussed via some computer simulations. The work provides a feasible method of multi-channel processing for the 3D MSAR.