SAR techniques and passive radar, final report

The project "SAR techniques and passive radar" has been carried out 2018-2020. The aim has been to investigate the possibility of passively imaging, detecting and positioning ground and sea targets with synthetic aperture radar (SAR) from an airborne platform. Passive SAR imaging means that non-cooperative transmitters (e.g. digital TV) illuminate the target area whereas the own platform receives the reflected signal and processes it into a SAR image. Covert operation is facilitated since signals are not transmitted from the own platform. The project has conducted flight trials with equipment installed on-board FMV's test aircraft TP86 Sabreliner. Good results have been achieved with sensor-targets distances up to approximately 50 km. Sea surveillance is a promising application and passive imaging of moving ships east of Gotland has been demonstrated. Passive SAR images of Norrköping's harbour and Landvetter's airport close to Göteborg are also included, as well as a comparison of active and passive SAR images from an area west of Skövde. The report describes signal processing methods which have been developed and discusses how the results are affected and limited by the current system, notably the array antenna and the data recording system.