SAR interferometry and statistical topography

We introduce a parametric model for the power spectrum density of SAR interferograms. This model is derived by assuming the interferogram as a stationary frequency modulated process, and by exploiting the statistical description of earth topography provided by multi-fractal fields. Despite the small number of parameters involved (3-6 in most cases), the model have been proven robust and accurate in most of the case tested. In particular, the parametric probability distribution assumed for ground terrain slopes fitted the actual histogram (derived from existing DEMs) in a range of 3–5 decades. Applications to blind baseline estimation and phase unwrapping are then briefly discussed.