АНАЛИЗ ПОДСТИЛАЮЩЕЙ ПОВЕРХНОСТИ ПРИ ФОРМИРОВАНИИ ИЗОБРАЖЕНИЯ В РЕЖИМЕ ДОПЛЕРОВСКОГО ОБУЖЕНИЯ ЛУЧА

Abstract

Radar based on real beam scanning is widely used in both civil and military spheres. However,it is difficult to realize high azimuth resolution of a stationary platform or a platform with nonuniformmotion using conventional signal processing algorithms. Doppler beam sharpening (DBS)technology is a combination of high resolution and real-time performance compared to SyntheticAperture Radar (SAR) technology, which uses the Doppler shift between echoes from objects on theunderlying surface along the azimuth direction, caused by the movement of the radar platform. Unfortunately,the traditional DBS imaging algorithm, which constructs a Doppler filter using an FFT,has a low azimuth resolution and a high level of side lobes, which limits further improvement in azimuthresolution. In the article, the algorithm for constructing a map of the underlying surface in thedirection of movement of the radar carrier based on the DBS was studied and the map image wasanalyzed using the Fourier transform. A three-dimensional view of the map of the underlying surfaceis shown with the distribution of values in the images. The subject of the study is the method and algorithmfor constructing a map of the underlying surface in the Doppler beam sharpening mode andidentifying chain structures based on the analysis of the Fourier transform. The object of the study is a set of test images of the terrain map. The result of the study is the development of an algorithm forconstructing a map in order to identify chain structures on the underlying surface. The novelty of thework is an algorithm that allows you to build a map of the underlying surface based on the DBS,taking into account the blind zone in the direction of movement of the radar carrier. The results obtainedalso make it possible to reveal chain structures in the region of interest. The possibility ofestimating the periodicity of image elements using the Fourier transform has been tested. As a resultof solving the tasks set, the following conclusions can be drawn: – an algorithm has been developedfor constructing a map of the underlying surface based on DBS with image correction in the directionof movement of the radar carrier. – analysis of the results of the study showed that the proposed algorithmallows you to identify chain structures on the map.