DIGITAL GENERATION OF SYNTHETIC APERTURE RADAR IMAGES

摘要

In a method for digital generation of synthetic aperture radar (SAR) imagesobtained by means of a coherent imaging system a signal compression in theazimuth and/or range direction is carried out with high resolution by meansof a subaperture configuration. A stepwise linear approximation of aquadratic phase characteristic is performed with regard to a referencefunction and frequency overlapping of the subapertures is effected foroptimizing the approximation of the phase characteristic. For the formationand synthesis of the subapertures complex multiplications are carried out,the signal of each subaperture thereby being shifted in the frequency. Theindividual subapertures are integrated twice by means of the movingaverage method for reducing the side lobes of the low resolution impulseresponse and after a time shift for equalizing the relative positioning of thesubapertures and after the complex multiplications for the frequency shiftthe results obtained in the individual subapertures are coherentlysummated.