TerraSAR-X-based Ground Control Points

Astrium Services’ spaceborne approach to obtaining 3D ground information for georeferencing or targeting is of significant interest for areas where little or no such information is available or can not be obtained easily, for example in remote locations or in areas where ground truthing can be hazardous or may not be authorised.

Based on stereo imagery or multiple image datasets, information such as digital elevation data and GCPs can be obtained at an outstanding quality, fully independent of weather conditions and daylight.

Three Standard Accuracies

TerraSAR-X delivers GCPs of three standard accuracies:

• TerraSAR-X GCP-1: using multiple High Resolution SpotLight scenes (HS) (~ 1m ground resolution), five GCPs (standard) with up to 1m accuracy in X/Y/Z are identified in an area of ~ 20km².
• TerraSAR-X GCP-2: combination of SpotLight (SL) and StripMap (SM) scenes (~ 1,5m / ~ 3m ground resolution), eight GCPs with up to 2m accuracy in X/Y/Z are identified in an area of up to 1,000km².
• TerraSAR-X GCP-3: using multiple StripMap acquisitions (~ 3m ground resolution), ten GCPs with up to 3m accuracy in X/Y/Z are identified in an area of ~ 1,000km².

Comprehensive Package of Deliverables

The GCP data are delivered to the customer as a comprehensive package containing not only the X/Y/Z-coordinates of the GCP, but a radar image chip of the surroundings (max. 500m x 500m) on each GCP, a location sketch, a written report to the product as well as a corresponding .kmz-file and metadata as .xml-file.