Processing, surface cover mapping and analysis of spaceborne radar data over Mono Lake/Long Valley using surface roughness generated from SIR-C/X-SAR imagery (California).

摘要

Surface cover analysis was conducted over the Mono/Long Valley region of California, using SIR-C/X-SAR. Surface cover was mapped based on surface physical roughness characteristics derived from variation in radar scattering. Two methods were explored for the purpose of removing topographic effects (primary contributor to backscatter) from SAR data sets. The first method utilized a DEM through which topographic effects were calculated and subtracted from SAR intensity values. Results from this procedure showed topographic correction failed in much of the imagery due to coregistration errors between DEM and SAR imagery. The second method was successful and used ratioing of scenes and Principal Components analysis to cancel out topographic effects. Finally, a SAR multiband image cube was constructed to facilitate the analysis of SAR backscatter intensity values (as spectral plots) vs. target and location. Results show several cover types are delineated and conform to Rayleigh roughness criteria, though resolution is the limiting factor.