Interferometric technique for determining the average height profile of rough surfaces

A new angular correlation phenomenon called the “angular memory effect” (AME) is applied to interferometric SAR (InSAR). Two transmitters illuminate the surface and the scattered waves are observed at two receivers. The mutual coherence function (MCF) for the scattered waves shows that the phase is linearly related to the average topographic height. This is extended to the two-frequency MCF which shows the relationship between the pulse arrival times and the height profile. The theoretical results are confirmed by experiments and numerical simulations