Multiscale Fusion of Insar Data for Hydrological Applications

Accurate determination of topography is required for a wide range of civilian and governmental applications. For example, modeling flood extent, flow velocity, and sediment transport associated with river networks requires bare-surface elevations with sub-meter height accuracy and spatial resolutions better than 10 meters. Strip-map interferometric synthetic aperture radar (INSAR) sensors have been used extensively to map topography. However, most INSAR data have insufficient spatial resolution and height accuracy for high-resolution flood modeling. We combine space-borne INSAR data from the ERS-1/2 platforms with multiple sets of airborne C-band INSAR data acquired by the NASA/JPL TOPSAR platform to obtain statistically optimal high-resolution estimates of topography over the Finke River Gorge in central Australia. We fuse the INSAR data using a multiscale Kalman smoothing approach. The estimated topography preserves the spatial resolution of the TOPSAR data while smoothing noise and providing estimates where there was no TOPSAR coverage.