A New Method of Resolving Velocity Ambiguities in Multi-Channel Interferometric SAR/GMTI

Along-track interferometry is an effective technique of the land clutter suppression for ground moving target indication (GMTI). Based on the principle of clutter cancellation in dual channels along-track interferometric synthetic aperture radar (SAR), the performance of relocation and radial velocity estimation in the three channels SAR/GMTI is analyzed, and a set of analytical formulas is derived. To solve velocity ambiguities resulted from interferometeric phase, unequal separation four channels along-track interferometric SAR/GMTI scheme is proposed, and the method of resolving velocity ambiguities is presented in detail. In addition, irregular spacing of sub-aperture help to exclude blind velocities and improve detection probability. Theoretical analysis and simulation results show the validity of this scheme