Recent developments in ground-based, polarimetric synthetic aperture radar imaging at the University of Sheffield

The authors describe various aspects of a programme of research directed towards the development of a ground-based polarimetric synthetic aperture radar (GB-SAR). The system will be of value in providing a better understanding of the vast amounts of image data being generated by current and future airborne and spaceborne SAR platforms. This attribute arises from the ability of the system to produce very high resolution polarimetric images under highly controlled conditions. The authors present the principles of the technique together with a description of the multi-frequency imaging algorithm which is efficient and very appropriate for the near-field geometry concerned. A description of the present indoor measurement facility is given and a series of results are described which demonstrate the imaging capabilities of the current configuration. Calibration procedures have been implemented successfully and the images are shown to be capable of providing useful quantitative RCS information. Furthermore, the polarimetric capability of the system is demonstrated quantitatively and visually for both metallic and vegetation targets. In addition imaging of a random surface has been carried out.