NEW AUTOFOCUSING TECHNIQUE FOR SAR IMAGES BASED ON THE WIGNER-VILLE DISTRIBUTION

High resolution images can be obtained with synthetic aper ture radars, by exploiting the motion between the air craft carrying the radar and the observed scene, if the relative motion parameters are known exactly. There exist some techniques for estimating these parameters from the collected data, but only for specific cases (linear and quadratic phase error). A technique for compensating phase errors whatever their time variation is proposed. The proposedtechnique is based on a joint time-frequency analysis of the received signal, carried out using the Wigner-Ville distribution. © 1990, The Institution of Electrical Engineers. All rights reserved.