Cherepnin H. Detection of unmanned aerial vehicles against the background of the sky by their radio thermal radiation

The work contains the theoretical foundations of the construction of multi-frequency radiometric complexes for the detection of UAVs against the background of atmospheric radiation. The method of processing signals of own radiothermal radiation in a radiometric complex operating in the X, Ka and W wave ranges has been synthesized and investigated. The structure and components of the work were aimed at obtaining a set of theoretical results with their confirmation by experimental measurements. At the same time, the theoretical substantiation of the foundations of the construction of a multi-frequency radiometric complex of UAV detection was based on a constructive combination of mathematical methods of the statistical theory of the synthesis of radio systems and practical experience in the construction of radiometric systems. The proposed technical solutions for the construction of promising airspace control complexes were obtained on the basis of the use of precise methods of solving optimization problems of statistical synthesis using the achievements of functional analysis, the theory of optimal solutions and estimation of the parameters of probability distributions. Analytical expressions for potential performance characteristics of radiometric complexes and calculated limit detection ranges for UAVs observed against the sky background were obtained and analyzed. On the basis of the obtained methods, a structural diagram of the radiometric complex was developed, and a database of radiometric contrasts of various types and classes of UAVs observed statically under various tactical and weather conditions was obtained in a wide range of waves, and full-scale UAV detection experiments were conducted. Practical and methodological developments in the construction of radiometric complexes, conducting experimental studies, selecting frequency ranges in order to increase the accuracy of radiometric measurements were obtained taking into account the meteorological conditions of the atmosphere. The effectiveness of the approach investigated in the work for solving the task of detecting UAVs against the sky, as well as the efficiency of the proposed technical solutions in its practical implementation, has been demonstrated experimentally and theoretically. The structure and components of the dissertation research are aimed at obtaining theoretical results and their confirmation by experimental measurements. The database of obtained radiometric contrasts of UAVs against the background of cloudless and cloudy atmosphere, rain will be the basis for forecasting the effectiveness and development of new technical solutions to increase the capabilities of airspace monitoring tools for detecting UAVs, which are created for the needs of protecting the critical infrastructure of Ukraine. It is theoretically shown that when developing a radiometric complex using domestic components of the millimeter and centimeter wave ranges, the maximum detection ranges are within the range from 1 to 3 km, and when using the best UHF elements of the world companies GmbH (RPG), Pasternack Company, Millimeter Wave Products Inc. the maximum detection distances of UAVs can reach 6 - 8 km. The purpose of the study is to increase the probability of UAV detection in any weather and tactical conditions of measurement due to experimental research of the layout of the X, Ka and W waveband radiometric complex. The object of the study is the UAV's own radio-thermal radiation and the signals received by the radiometric complex in the X, Ka and W wave ranges. The subject of the research is statistically optimal methods, algorithms and devices for processing the own radio-thermal radiation of UAVs in various tactical and weather conditions.