Estimation of residual motion error in airborne InSAR based on backprojection and multisquint techniques

For airborne repeat-pass synthetic aperture radar (SAR) interferometry (InSAR), precise trajectory information is needed to compensate for deviations of the platform movement from a linear track. Due to the inaccuracy of current navigation systems, residual motion errors (RME) exist between the real and measured trajectory, causing phase undulations in the final interferograms. In this paper we present for the first time the combination of the time-domain backprojection and multisquint techniques for RME estimation. Repeat-pass data over Slumgullion landslide are used to demonstrate the feasibility of RME estimation for both stationary and non-stationary scenes.