A.A. Monakov – Dr.Sc.(Eng.), Professor, Department of Radio Systems, 

Saint-Petersburg State University of Aerospace Instrumentation E-mail: a_monakov@mail.ru

Range cell migration is one of the reasons for defocusing images in radars with synthesized antenna aperture (SAR). There are two groups of signal processing algorithms for SAR, which compensate for the migrations. The first group includes algorithms that use the recalculation of the signal from the coordinate system «slant range - azimuth» into the system «along-track range – cross-track range» using methods of function interpolation. The disadvantage of these algorithms is the large computational costs. The algorithms of the second group do not use interpolation. However, they are synthesized on the assumption that the transmitted signal is a chirp pulse, and its matched filtering is realized when the algorithm itself is implemented. In the article an algorithm is synthesized that is free from these shortcomings: the algorithm is applicable for processing of any wideband signals, the matched filtering is realized at the beginning of processing, separately from the algorithm. Verifying the quality of the algorithm by mathematical simulation has proven its high efficiency.

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