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The possibility of increasing the information content of radar methods for observing spacecrafts has been investigated. A method for identifying the geometric shape of local reflectors is proposed, based on the combined application of polarization methods and a model of scattering of electromagnetic waves described by the geometric theory of diffraction. The main features of the implementation of the proposed method are considered, and the results of its approbation in the problem of analyzing the local reflectors of a low-orbit spacecraft are presented. It is shown that the proposed method makes it possible to expand the range of geometric types of identifiable reflectors and to evaluate the geometric shape of the corresponding structural elements.

On the basis of an analytical review of scientific and technical information sources dedicated to correction of errors in the gainphase distribution of the field on the aperture of the phased antenna array, such errors been caused by correlation of errors in phase quantization by discrete phase shifters, and also caused by disbursement of their characteristics and by failures in a part of the phased antenna array elements, an unresolved problem has been discovered. It is required to correct the amplitudephase distribution errors caused by deformation of the curtain of the large-aperture stationary phased antenna array and resulting in deviation of the radiating elements from their design parameters. A mathematical apparatus of the field distribution electronic correction is being developed together with an algorithm for controlling the radiation pattern of the phased antenna array. The effectiveness of the proposed method for correcting the array pattern distribution on the aperture of the deformed phased antenna array has been evaluated and an option for technical implementation thereof has been proposed.The relevance and novelty of the work is confirmed by the patent for the invention developed on the basis of the studies performed and by the certificate of state registration of the software, which was based upon in the processing of results of the measurements of the deformations in the curtain of the large-aperture phased antenna array.

The data about the effect of image quality on accuracy of information parameters are presented. Studies on accuracy of measuring characteristics of objects in their images depending on image quality are described. Studies showed that accuracy of measurement algorithms improves with an increase in sample sizes of frames in the optoelectronic system (OES). Image quality is improved by processing the frame samples with algorithms for increasing resolution and reducing noise levels, both in single-point and multi-position OESs based on digital cameras with matrix photodetectors. The maximum effect of an increase in information content of the image and accuracy of measuring algorithms is determined by variations in the pixel structure of each image in the region of brightness gradient boundaries. In the single-point OESs which ensure high quality of optical images without noise factors and variations of other external parameters, the optimal number of frames in the OES is four.