Precision terrain mapping using large baseline interferometry

Veridian ERIM International, with support from the US Air Force and the Defense Advanced Research Projects Agency Tactical Technology Office (DARPA/TTO), has developed an airborne X-band SAR system capable of collecting single-pass interferometric SAR data with cross-track baselines of 7.5 m, 15 m, and 30 m. SAR data have been collected over several sites with varying terrain and groundcover type. These data have been formed into 1-foot resolution imagery and interferometric processing has produced digital elevation data with post spacings of 1 m. The resulting elevation data have been compared with LIDAR elevation data in order to estimate the accuracy of the SAR elevation measurements. SAR elevation data with accuracy approaching the draft Level 5 specification for precision elevation data have been produced.