Synthetic aperture radar imaging by one bit coded signals

Processing of synthetic aperture radar (SAR) data coded with one bit is considered. The one bit coding operation amounts to the retention of only the information about the sign of the signals involved (signum coding or SC). The paper reviews the theory of signum coding and evaluates its performance by computing some quality measures for real images. Numerical results, which are in accord with theory, show that only a slight degradation in the quality of the images obtained is introduced by the SC operation if the signal is sampled at a rate consistent with the original bandwidth. If the sampling frequency is increased, the quality obtained can be further improved. Since the data involved in the processing are binary sequences, the processing can be carried out in real time, on-board the moving platform carrying the SAR antenna, and by using dedicated hardware consisting of simple, small, low-cost devices, which can be on motherboards of small dimensions and absorb very little power