Using multi angular radar data to discriminate the influence of rough surface scattering on soil moisture inversions over bare soils

It is well known that the angular response of radar backscattering is strongly influenced by surface roughness. Attempts to exploit this result in soil moisture or roughness inversions are however practically non-existent, maybe because multi angular satellite data are only starting to be available. Experimental data shows how the difference between signals at 20° and 30° incidence angles is 10× more sensitive to surface roughness degradation than is the difference between hh and vv polarizations at same incidence and 9.4 GHz. Extensive simulations with IEM show that this result can be exploited for soil moisture inversions, if the surface correlation function is close to exponential