High resolution VHF SAR processing using synthetic range profiling

This paper demonstrates the use of stepped-frequency waveforms to obtain high resolution SAR images without imposing severe instantaneous bandwidth requirements on the radar system. Although azimuth compression and motion compensation are essential to obtain high resolution SAR images, this paper only discusses how to obtain high range resolutions. Especially at VHF frequencies it is very difficult to obtain high range resolutions, because the effective pulse bandwidth required would amount to a large percentage of the centre frequency. After briefly introducing the theory of synthetic range profiling as applied to SAR, this paper goes on to discuss the synthetic range profile of an A320 Airbus, which serves to demonstrate the feasibility of synthetic range profiling. More attention is then given to simulation results, which introduce the problems encountered when sampling the returning echo waveforms.