DEM generation using ERS-1/2 interferometric SAR data

Accurate digital elevation model (DEM) can be producted by using interferometric SAR data. The authors have developed a new software on PCs that can automatically generate DEM from single look complex SAR pairs. The least-squares image matching method based on SAR multi-look intensity images has been used to register complex image pair. The typical accuracy of 0.02-0.04 pixel size can be obtained on multi-look SAR images. They also present a new set of equations for calculating three dimensional coordinates at each pixel from unwrapped phases. The orbital position, attitude and baseline as well as phase constant have been involved in the equations. Using at least six ground control points, it is possible to refine interferometric baseline, and estimate the phase constant, the orbit and attitude parameters simultaneously. Test results are provided for ERS-1/2 interferometric SAR scene pair acquired over Etna area in Italy