MOTION COMPENSATION STRATEGY FOR AIRBORNE DIFFERENTIAL INTERFEROMETRIC SAR DATA

摘要

Differential interferometry has become a powerful andrnestablished technique for detecting and monitoring differentrngeophysical phenomena as landslides, glacier flows,rnand Earth surface deformations. As opposed to the spacebornerncase, the application of this tool to airborne SARrndata is still not well-established. In fact, differential interferometryrnfrom airborne SAR platforms is preventedrnby the insufficiently accurate motion compensation of thernaircraft movement that, if not well performed, can introducernseveral phase errors that must be compensated tornachieve the accuracy required for its applications.rnThis paper introduces a processing chain and a motionrncompensation strategy specifically designed to processrntime series of airborne SAR data acquired over rapidlyrndecorrelating areas (e.g. agricultural fields). Roughly,rnit consists in a post-processing motion compensation involvingrnthe computation of a cumulative correction to bernembedded at a raw data level. After having re-processedrnthe entire data stack, the residual baseline error is reducedrnto the order of millimetres.rnThe approach is then tested on a time series of SAR datarnacquired by the DLR’s F-SAR sensor over the agriculturalrntest site of Wallerfing (Germany).