InSAR image co-registration using the Fourier-Mellin transform

The problem of interferometric SAR (InSAR) image co-registration is addressed. Classical InSAR matching considers only the translation shift between two complex images. However, for accurate radar image matching (different swaths, paths, or aspects angles), other shift parameters would be useful. For two-dimensional images, the application of the Symmetric Phase Only Matching Filtering (SPOMF) to the Fourier-Mellin Invariant (FMI) descriptors allows an accurate and efficient registration of translated, rotated and scaled images. This paper discusses the utility and feasibility of the SPOMF technique on the FMI descriptors of two interferometric SAR images. The FMI-SPOMF technique is applied on different pairs of InSAR data corresponding to areas with different relief types, in France, Nepal and Tunisia. The results are compared with those of classical cross-correlation registration techniques. We find that the FMI-SPOMF descriptors of an interferometric pair of images allows more precise co-registration and moreover could decide on the exploitability of a given interferometric pair.