Reflectivity and DEM Estimation from Multi-baseline Complex SAR Signals

Multi-baseline interferometric Synthetic Aperture Radar (In-SAR) systems are used to obtain increased accuracy Digital Elevation Model (DEM) of the observed ground scene. The techniques which are commonly used exploit only the interferometric phase information, and are based on Maximum Likelihood (ML) estimation. Due to the difficulty of express the multi-baseline likelihood function in closed form, they adopt the statistical independence approximation of the interferometric phases. In this paper we present a method exploiting both amplitude and phase of the interferometric images, and allowing to express the multi-baseline likelihood function in closed form. It has also the advantage of correctly performing multi-baseline speckle reduction on the image intensity.