Separable space-time pattern synthesis for SBR sparse aperture array GMTI

In this paper, a novel GMTI method is proposed for spaceborne sparse aperture radar using separable space-time processing. The extremely long baseline of a sparse aperture array can provide a narrow main beam at he cost of large number of grating lobes. To suppress ground clutter caused by grating lobes, a Doppler filter is applied at the output of the sparse array. An efficient, yet robust projection method is used to solve the Doppler filter coefficients, which is an ill-posed problem. More than -30 dB substantial gains can be achieved after sparse array beamforming and Doppler filtering.