Terrain Topographic Inversion Using Single-Pass Polarimetric SAR Image Data

摘要

It has been studied that the shift of polarization orientation angle Ψ at the maximum of co-polarized or cross-polarized back-scattering signature can be converted to the surface slopes. It is then utilized to generate the digital elevation mapping (DEM) and terrain topography using two-pass fully polarimetric SAR or interferometric SAR (INSAR) image data. This paper, using the Mueller matrix solution, newly derives the Ψ shift as a function of three Stokes parameters, I_(vs), I_(hs), U_s, which are measured by polarimetric SAR image data. Using the Euler angles transformation, the orientation angle Ψ is related to both the range and azimuth angles of the tilted surface and radar viewing geometry. When only a single-pass SAR data is available, the adaptive thresholding method and image morphological thinning algorithm for linear textures are proposed to first determine the azimuth angle. Then, making use of full multi-grid algorithm, both the range and azimuth angles are utilized to solve the Poisson equation of DEM to produce the terrain topography.