A proposal for a SAR interferometric model of soil moisture

Since long it is known that SAR interferometric observables are influenced by soil moisture variations, however there is a lack of scattering models that link interferometric observables and variations of the dielectric properties. In this work we propose a model based on plane waves and Born approximation, deriving first the vertical wavenumbers in the medium as a function of geometrical and dielectric properties and successively the interferometric coherences. It is observed that soil moisture behaves on the phase in a similar way as tomography does, breaking the phase consistency in triplets of interferograms. This property, along with coherence magnitudes, is exploited in an attempt at moisture inversion on real data.