Mission planning for synthetic aperture radar surveillance

The Microwave Radar Division of the Defence Sciences and Technology Organisation (DSTO) employs synthetic aperture radar to obtain high-resolution images of selected ground targets. It uses this device, mounted on an aircraft, to scan up to 20 rectangular regions called swaths to obtain images with resolutions down to one meter. Missions consisting of a designated sequence of swaths and flight paths are planned using mapping software. Previously DSTO had been determining the best tours for missions by visually tracking possible swath sequences from a starting base to an ending base. This method was time consuming and did not guarantee optimality in terms of distance traveled. We developed optimization software tools to plan mission tours more efficiently. DSTO can now plan missions with up to 20 swaths in a few seconds, rather than the hour it took using the visual approach. Proposed tour lengths show an average improvement of 15 percent over those manually produced. The software incorporates methods for dealing with the operational problems of no-fly zones and shadowing associated with images.