Combination of repeat and single-pass dual-frequency airborne InSAR data for accurate height estimation

The use of repeat-pass-large-baseline SAR interferometry to generate highly accurate digital elevation models (DEMs) has not been as exploit as the use of single-pass interferometry. This is mainly due to issues associated with the small height of ambiguities (HoAs) necessary to deliver the required height accuracy, and with the temporal and geometrical decorrelation typical of repeat-pass systems. Although airborne systems are very attractive for the flexible baseline choice in repeat-pass mode, when using airborne datasets, the processing of the DEMs should account for uncompensated residual motion errors and other phase artefacts. In this paper we describe a methodology for generating accurate DEMs combining single- and repeat-pass data from dual frequency (X- and S-band) F-SAR acquisitions.