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В статье рассматриваются вопросы теории и практики радиолокационного обнаружения, способы обнаружения вражеских объектов при разных видах радиолокации и способы повышения требуемого качества радиолокационной информации, выполняющей функции системы разведки и оповещения для системы ПВО.Отмечается, что радиолокационное распознавание классов воздушных объектов – это необходимость для радиолокационной системы, выполняющей функции системы разведки и оповещения для системы ПВО (ВКО). Однако в условиях применения активных шумовых помех активная радиолокация не позволяет выполнить возлагаемые на нее задачи без существенного качественного изменения энергетических ресурсов, ее потенциальные возможности практически исчерпаны.Делается вывод о том, что одним из возможных путей разрешения невозможности достижения требуемого качества радиолокационной информации в условиях применения активных шумовых помех только за счет средств активной локации, даже объединенных в систему в практике, является комплексирование информации от средств активной и полуактивной локации., This article examines the theory and practice of radar detection, ways of detecting enemy objects in different types of radar and methods of improving the required quality of radar information serving as a reconnaissance and warning system for an air defence system.It is observed that radar recognition of classes of airborne objects is a necessity for a radar system that serves as a reconnaissance and warning system for the air defence system (ADS). However, under conditions of active noise interference, active radar cannot fulfil its assigned tasks without a significant qualitative change of energy resources, its potentialities are practically exhausted.It is concluded that one of the possible ways to resolve the impossibility of achieving the required quality of radar information in conditions of active jamming only at the expense of means of active location, even combined into a system in practice, is a combination of information from means of active and semi-active location., Международный научно-исследовательский журнал, Выпуск 7 (133) 2023

Международный научно-исследовательский журнал, Выпуск 7 (133) 2023

В обзорной статье рассматриваются перспективные разработки моделей беспилотных грузовых автомобилей основных российских компаний. Представлено обобщенное оборудование для обеспечения возможности беспилотного управления автомобилем. Показаны перспективы и возможные сферы применения беспилотных грузовых автомобилей. Анализ показал целесообразность развития беспилотного управления транспортной техникой, внедрения интеллектуальных платформ, способных коммуницировать с беспилотными автомобилями. Развитие скоростных автомобильных магистралей с использованием цифровых технологий способствует созданию отдельных конструктивных изменений, направленных на улучшение эксплуатационных характеристик и потребительских свойств автомобилей., The review article examines promising developments in the models of unmanned vehicles of the main Russian companies. The generalized equipment for enabling unmanned truck control is presented. The prospects and possible applications of unmanned vehicles are shown. The analysis has shown the expediency of developing unmanned control of transport vehicles, and the introduction of intelligent platforms capable of communicating with unmanned vehicles. The development of high-speed highways using digital technology contributes to the creation of certain design changes aimed at improving the performance and consumer properties of vehicles., Международный научно-исследовательский журнал, Выпуск 1 (127) 2023

Международный научно-исследовательский журнал, Выпуск 1 (127) 2023

The article discusses the issues of forest canopy research. A solution to the problem of monitoring the state of the stand by probing with a high-frequency electromagnetic wave is proposed. This solution will find application in taxation and other Forestwork. В статье рассмотрены вопросы исследования лесного полога. Предложено решение проблемы мониторинга состояния древостоя путем зондирования электромагнитной волной высокой частоты. Данное решение найдет применение в таксации и других лесохозяйственных работах.

В статье предложен анализ радиопередатчиков, работающих в диапазоне ультракоротких волн, в качестве удобного источника сигнала для определения дальности обнаружения в пассивном бистатическом радиолокационном измерителе координат. Представлен теоретический анализ основных специфических особенностей бистатической пассивной радиолокационной станции, рассмотрены ее энергетические характеристики, а также воздействие различных видов шума при мгновенном приеме сигнала прямой подсветки и слабых сигналов, отраженных от объекта. Проведена оценка бистатических характеристик пассивной технологии при проектировании таких радиолокационных станций дальнего обнаружения объектов, а также исследован динамический диапазон приемного устройства пассивного радиолокационного измерителя координат при воздействии на него шума и мощность отраженного сигнала, которая базируется на эффективной площади рассеяния, что позволяет создать более эффективную бистатическую технологию пассивного обнаружения. Экспериментальные данные представлены в виде математического моделирования, которые включают в себя сканирование спектра диапазона ультракоротких волн в различных условиях для дальнего обнаружения объектов, рассмотрены несколько вариантов воздействия на диапазон различных условий местности и ландшафта. Результаты математического моделирования сопоставлены с теоретическим анализом специфических особенностей пассивного бистатического радиолокационного измерителя координат., The article proposes an analysis of radio transmitters operating in the ultrashort wave range as a convenient signal source for determining the detection range in a passive bistatic radar. A theoretical analysis of the main specific features of a bistatic passive radar is presented; its energy characteristics are considered along with the impact of various types of noise during instantaneous reception of a direct illumination signal and weak reflections from an object. The bistatic characteristics of the passive technology were evaluated when designing such radar for long-range object detection. Additionally, the dynamic range of the passive radar receiver when exposed to noise and the power of the reflected signal based on the effective scattering area, which makes it possible to create a more effective bistatic passive detection technology, was investigated. Experimental evidence is presented in the form of the mathematical modeling, which includes scanning the spectrum of the ultrashort wave range under various conditions for long-range detection of objects. Several options for influencing the range of different terrain and landscape conditions are considered. The results of the mathematical modeling are compared with the theoretical analysis of the specific features of a passive bistatic radar., МОДЕЛИРОВАНИЕ, ОПТИМИЗАЦИЯ И ИНФОРМАЦИОННЫЕ ТЕХНОЛОГИИ, Выпуск 2 (41) 2023, Pages 25-26

A method of long-term combined accumulation of the reflected signal is justified, which provides for its division into disjoint subsets, coherent accumulation in subsets using one of the fast algorithms and subsequent incoherent accumulation of the squares of the modules of the results of processing the subsets. A distinctive method’s feature is the use with incoherent accumulation of maxima of the squares of the moduli of the coherent processing results, that are selected from the range / radial velocity regions in accordance with a given hypothesis about the minimum and maximum values of the target radial velocity and the radial acceleration detection channel setting.The efficiency of the method was confirmed by simulation modeling. Using the theories of ordinal statistics and the method of moments, a method for calculating the probability of correct detection is developed. Estimates of processing losses are made in comparison with coherent and incoherent accumulation algorithms for a signal reflected from a point target, for the case when there is no range and frequency migration. Estimates for the required number of receiver channels are given.

The features of the implementation of the algorithm for the synthesis of detail radar images for an aperture synthesis radar using the built-in functions of the Cuda library are presented. The estimation of computational complexity from the standpoint of the organization of parallel computing on Nvidia GPUs is given. The estimation of the real performance of radar synthesis is given, taking into account the volume and features of the placement of primary radar information.

Introduction. A radar image is an image obtained by remote sensing the earth's surface with a radar device. Radar images are characterized by background graininess caused by speckle noise, which should be filtered to improve the quality of radar images. The structure of speckle noise reduction filters often comprise one or more parameters to control the level of noise smoothing. The values of these parameters have to be selected experimentally. In works devoted to speckle noise filtering, the methods used for selecting filter paraments are rarely clarified.Aim. To present a methodology for selecting the parameters of multiplicative speckle noise filters on a radar image that are optimal in terms of the quality of the resulting image.Materials and methods. The article presents a method for determining the optimal parameters of speckle noise reduction filters. This method was applied to the most conventionally used filters. The search for optimal parameters and testing of the filters were carried out using a specially designed image, which contained the objects most frequently found on radar images. The structural similarity index (SSIM) metric was chosen as a metric that assesses the quality of filtration.Results. After determining the optimal (in terms of SSIM) parameters of speckle noise reduction filters, the filters were compared to select the best filters in terms of the quality of radar image processing. In addition, the operation of the filters under study was tested on images containing various types of objects, namely: large objects, small objects and sharp borders. Knowing which filter copes best with smoothing speckle noise in a particular area and what values of the variable parameters this requires, an optimal quality of radar images can be achieved. Filtering not only improves human perception of radar images, but also reduces the influence of speckle noise during their further processing (object detection, segmentation of areas, etc.).Conclusion. The proposed algorithm allowed optimal parameters for several speckle noise filters to be determined. The quality of filtration was assessed using an expert method (visually) by comparing images before and after filtration, differential images and one-dimensional image slices. The Frost filter and the anisotropic diffusion filter with optimal parameters showed the best processing quality according to the SSIM metric.

The article discusses the possibilities of estimating the states vectors of observation objects with the nonMarkovian approximation of the trajectories. The introduction discusses the problem consisting in the fact that the use of the approximation of the trajectory of the observed object by Markov processes in some cases can lead to a discrepancy between theory and practice. In the first section, we simulate the trajectories of observed objects when approximated by a Markovian process and indicate the limitations of this approach. It is proposed to use a multidimensional Gaussian distribution law for generating the trajectory of the observed object. In the second section, a study of the accuracy characteristics of a single-position angular-rangefinder radar and a three-position rangefinder radar are considered. Algorithms α-β, Kalman and nonlinear estimation are used in the modeling as estimation algorithms in these systems. The parameters and characteristics of the simulation are given. In the third part, the results of modeling the process of estimating the location of objects of observation with trajectories of movement approximated by non-Markov processes are presented. Modeling confirms the possibility of using submitted algorithms to estimate the trajectory of a smallsized object of observation, a trajectory model of which uses a multidimensional normal distribution law. It is pointed out that in several cases the filtering errors exceed the errors of a single measurement. This leads to the conclusion that further modification of the algorithms is necessary. In the final part, a recommendation is given on how to further reduce the estimation errors when using Kalman algorithms and nonlinear estimation.

Introduction. Synthetic aperture radars (SAR) are important components of aviation-based systems for remote sensing of the Earth. The current level of such systems allows simultaneous radar surveys in several frequency ranges. Such surveys require complexing of the images formed in each of the frequency channels, which task is yet to be resolved.Aim. To review the formation principles and methods for joint processing of images using space and aviation-based multi-band synthetic aperture radar systems.Materials and methods. The methodology of systems analysis, involving the integral stages of decomposition, analysis and synthesis, was used. Decomposition of integrating multi-band radar images was performed considering the effect of various factors on the characteristics of radar images in different frequency ranges. Such factors include the principles of radar imaging, issues of radar images of multi-band synthetic aperture radars with real characteristics, and complexing levels.Results. According to the classical systems approach, the results of review and analysis are corresponded by appropriate conclusions on the shortcomings of each decomposition element and the synthesis of a proposal for achieving the goal. It was shown that joint processing of multi-band radar images can be carried out at the levels of signals, pixels, features and solutions, as well as their aggregates. Each approach is characterised by its shortcomings, which impede implementation of full integration of multi-band radar images without loss of information, which is due to the absence of information redundancy of radar images, compared to, e.g., optical images.Conclusion. Recommendations on the application of a particular method and the synthesis of a system for radar complexing images based on the texture-fractal approach were formulated. Directions for further work meeting all the requirements for completeness, reliability and information content of remote sensing of the Earth were outlined.

В статье рассмотрены современные методы активного дистанционного зондирования, которые могут применяться для мониторинга состояния магистральных нефтепроводов и защитных сооружений при них. Целью работы является анализ характеристик радиолокационных съемочных систем Sentinel-1 и ICEYE, таких как режим съемки, ширина полосы захвата, пространственное разрешение и поляризация радиосигнала. Выполнены экспериментальные исследования методики предварительной обработки данных в программном продукте SNAP и рассмотрены ее основные этапы. В результате определены характеристики данных радиолокационной съемки, позволяющие использовать их для оценки состояния магистральных нефтепроводов, выделены преимущества и недостатки., The article discusses modern methods of active remote sensing, which can be used to monitor the condition of oil trunk pipelines and the protective structures around them. The aim of the work is to analyze the characteristics of Sentinel-1 and ICEYE radar survey systems, such as shooting mode, capture bandwidth, spatial resolution, and polarization of the radio signal. The author carries out experimental studies of the data preprocessing technique using the SNAP software and examines its main stages. As a result, the study determines the characteristics of the radar survey data, allowing them to be used to assess the condition of oil trunk pipelines, advantages, and disadvantages were also highlighted., Международный научно-исследовательский журнал, Выпуск 4 (118) 2022, Pages 20-23

Поступила: 18.07.2022. Принята в печать: 19.09.2022. Received: 18.07.2022. Accepted: 19.09.2022. Рассмотрены основные факторы, влияющие на эффективность автоматической системы распознавания объектов на радиолокационном изображении, полученном с помощью радиолокатора с синтезированной апертурой антенны. Разработан алгоритм кластеризации для выделения объектов на радиолокационном изображении. Приведены результаты применения алгоритма кластеризации радиолокационного изображения, позволяющего повысить вероятность правильного распознавания объектов. Приведен анализ эффективности применения алгоритма кластеризации в зависимости от порогового обнаружения. Разработана и приведена структура двухэтапной системы алгоритма автоматического распознавания объектов на радиолокационном изображении. The main factors influencing the efficiency of an automatic object recognition system in a radar image obtained with a synthetic aperture radar are considered A clustering algorithm of selecting objects on a radar image has been developed. The results of applying the radar image clustering algorithm, which makes it possible to increase the probability of correct recognition of objects, are presented. An analysis of the effectiveness of the application of the clustering algorithm depending on the threshold detection is given. The structure of the two-stage system of the algorithm of the automatic recognition of objects on a radar image has been developed and presented.

В статье оценена роль радиолокаторов с синтезированной апертурой (РСА) в системах дистанционного зондирования Земли. Проведён анализ таких тенденций развития средств дистанционного мониторинга с борта космических носителей, как повышение информативности и оперативности. Выявлены перспективные направления развития подобных систем., We assess the role of synthetic aperture radars (RSA) in Earth remote sensing systems. The increase of informative value and efficiency are analyzed as the trends in the development of remote monitoring tools from space carriers. Promising directions for the development of the systems in question are identified., ВЕСТНИК ОБРАЗОВАНИЯ И РАЗВИТИЯ НАУКИ РОССИЙСКОЙ АКАДЕМИИ ЕСТЕСТВЕННЫХ НАУК, Выпуск 1 2022

В статье предлагается простой метод радиофотонных измерений доплеровского сдвига частоты и угла прихода эхосигналов в системах автономного вождения, который позволяет удобно и точно получать информацию путём сравнения частоты и фазы огибающих биений двух каналов, разделённых по поляризации, за малый период времени. О знаке ДСЧ и его значении при угле прихода 90° можно судить благодаря введению опорного гетеродинного сигнала с заданной частотой и фазой. В модуле, реализующем метод, используются два параллельных тандемных амплитудно-фазовых модулятора для получения двухчастотных сигналов с подавленной несущей и разностной частотой, равной частоте сигналов системы: локационного, гетеродинного и двух эхосигналов с соседних элементов антенной решётки. В первой части статьи приведён сравнительный анализ существующих радиофотонных методов и средств одновременного или практически одновременного измерения доплеровского сдвига частоты и угла прихода и описан принцип действия модуля, реализующего предложенный метод, оценочно показаны его преимущества и недостатки. Целевые характеристики, предполагаемые к достижению, заключаются в измерении доплеровского сдвига частоты в диапазоне ± 100 кГц и диапазоне локационных частот 15–40 ГГц с погрешностью в ±10 Гц и измерении угла прихода в диапазоне от 0 до π/2 с погрешностью менее ±1,7 мрад., Introduction. One of the new, actively developing functions of radars, necessary for providing processes of intelligent or autonomous cars, is determining the location and motion parameters of other objects in real time, which includes the simultaneous measurement of the Doppler frequency shift (DFS), as well as the angle of arrival (AoA) of the echo. Recently, due to the advantages of large instantaneous bandwidth, low transmission losses and resistance to electromagnetic interferences, a lot of methods based on radio photonics technologies have been developed to implement radio measurements of DFS and AoA in the optical range. The aim of the research was to develop the principle of operation of a new simple radio photonic system for simultaneous measurements of DFS and AoA, which obtains information by comparing the frequency and phase shift values, respectively, of the down-converted signals of two channels. Moreover, the use of a reference signal, the reference frequency and phase allows to get the sign of the DFS, and the AoA from the direction of a perpendicular to the line connecting two reception antennas. Methods. It is proposed to build a circuit of a block of modulators for measuring DFS and AoA based on tandem single-port amplitude and phase modulators (TAPM) that implement the Ilyin-Morozov single-frequency coherent radiation conversion method with complete carrier suppression and high spectral purity when the parameters of the amplitude-phase conversion deviate from the optimal ones. In the system being developed, location, reflected, and heterodyne radio signals are fed to two TAPMs, each defines one measurement channel with total carrier suppression. As a result, the DFS (including the value and sign) and the AoA can be obtained from the analysis of the signals of each channels in terms of the parameters of their beat envelope. Conclusion.Thus, the first part of the paper presents the principle of operation of the module, which has a very simple structure and low cost. A wide operating frequency range determined by the modulator bandwidth, and a low-frequency photodetector provide high reliability due to a simple procedure for calibrating and controlling the temperature conditions of the elements. The target characteristics expected to be achieved and which will be presented in the second part of the paper are to measure the DFS in the range of ±100 kHz at operating frequencies of 15-40 GHz with an error of ±10 Hz and to measure the AoA in the range from 0 to π/2 with an error less than ±1.7 mrad., ВЕСТНИК ПОВОЛЖСКОГО ГОСУДАРСТВЕННОГО ТЕХНОЛОГИЧЕСКОГО УНИВЕРСИТЕТА. СЕРИЯ: РАДИОТЕХНИЧЕСКИЕ И ИНФОКОММУНИКАЦИОННЫЕ СИСТЕМЫ, Выпуск 3 (55) 2022, Page 58–71

Unmanned aerial vehicles (UAVs) have recently become widespread, because they are capable of performing a wide range of functions useful for mankind. At the same time, UAVs are a source of potential threats in a number of areas of human activity, namely, military, economic, and everyday life. Therefore, an urgent scientific and technical problem of detecting and observing UAVs has been formed recently to prevent them from performing unauthorized actions. The main means of UAV surveillance are radar (both active and passive), optical, infrared, acoustic stations, as well as complex systems in which joint processing of information obtained using these information channels is carried out. However, in general, the scientific and technical problem of monitoring UAVs, especially small UAVs, remains unresolved: the efficiency of UAV detection using all these methods remains insufficient, and the needs of practice are far from being fully satisfied with the available means. This article is devoted to the analysis of currently known scientific and practical results aimed to assess the possibility of detecting UAVs by radio signals scattered by acoustic disturbances of the environment created by UAVs, and to formulate urgent scientific and technical problems in this aria of knowledge., Беспилотные летательные аппараты (БПЛА) получили в последнее время значительное распространение, поскольку способны выполнять широкий спектр полезных для человечества функций. В то же время БПЛА являются источником потенциальных угроз в ряде областей деятельности человека – военной, хозяйственной, повседневной. Поэтому в последние годы сформировалась актуальная научно-техническая проблема обнаружения и наблюдения БПЛА с целью предотвращения выполнения ими несанкционированных действий. Основными средствами наблюдения БПЛА являются радиолокационные (как активные, так и пассивные), оптические, инфракрасные, акустические станции, а также комплексные системы, в которых осуществляется совместная обработка информации, получаемой с использованием указанных информационных каналов. Однако в целом научно-техническая проблема наблюдения БПЛА, особенно малых БПЛА, остается нерешенной: эффективность обнаружения БПЛА с использованием всех указанных методов остается недостаточной, а потребности практики имеющимися средствами удовлетворяются далеко не в полной мере. Cтатья посвящена анализу известных научных и практических результатов с целью оценки возможности обнаружения БПЛА по радиосигналам, рассеянным на акустических возмущениях среды, создаваемых БПЛА, и формулированию актуальных научных и технических задач в данной области знаний., Безпілотні літальні апарати (БПЛА) отримали значне поширення, оскільки здатні виконувати широкий спектр корисних для людства функцій. У той же час БПЛА є джерелом потенційних загроз у ряді областей діяльності людини – військовій, господарській, повсякденній. Тому в останні роки сформувалася актуальна науково-технічна проблема виявлення і спостереження БПЛА з метою запобігання виконання ними несанкціонованих дій. Основними засобами спостереження БПЛА є радіолокаційні (як активні, так і пасивні), оптичні, інфрачервоні, акустичні станції, а також комплексні системи, в яких здійснюється спільна обробка інформації, що була одержана з використанням зазначених інформаційних каналів. Однак в цілому науково-технічна проблема спостереження БПЛА, особливо малих БПЛА, залишається невирішеною: ефективність виявлення БПЛА з використанням всіх зазначених методів залишається недостатньою, а потреби практики наявними засобами задовольняються далеко не в повній мірі. Cтаття присвячена аналізу відомих наукових і практичних результатів з метою оцінки можливості виявлення БПЛА за радіосигналами, розсіяними на акустичних збуреннях середовища, створюваних БПЛА, і формулювання актуальних наукових і технічних завдань в даній області знань.

We obtained the analytical expressions for the mean square deviation of errors in estimating the angular coordinates of the target for quasi-optimal algorithms of processing the fluctuating signals in radar meters with a scanning multichannel receiving system under external interference. Analytical estimates are based on the construction and circulation of the Fisher information matrix with a joint estimation of the direction of arrival and power of the fluctuating reflected signal at the output of the isotropic receiving antenna and a parabolic approximation of the mean value of the decisive statistic in the vicinity of the target direction for the processing algorithm, which provides for an estimate of the average power of the reflected signal by the least square method. The research demonstrates the convergence of exact and approximate analytical estimates and the results of computer modeling. We present the results of studying the accuracy of determining the angular coordinates of the reflected signal for typical space-energy cases. It is shown that the estimation error of the angular coordinates of the reflected signal are unbiased, and at small intervals of the correlation of the reflected signal the probability density of estimation error of the target azimuth exhibits normal distribution. In case of large correlation intervals, the distribution significantly differs from normal and acquires a large positive kurtosis and asymmetry with their values depending on the angular differences of the interference source and the target. The obtained expressions can be used to evaluate the effectiveness of quasi-optimal radar meters in the conditions of external interference and in the complex modeling of radar facilities with such meters included.

This article discusses the application of complex methods for detecting, recognizing, distinguishing borders and measuring various parameters of noisy, low-contrast, difficult-to-see images of space, air or ground objects. The problem of detecting, recognizing, distinguishing and measuring parameters of objects images (space or air objects, aircraft, ship, ground transport, people, coasts, etc.) is still among the very complex, completely unsolved radio engineering and telecommunications (“connected”) tasks. Currently, infrared (IR) direction finding, optical (laser location) direction finding and radar are used to detect, recognize, distinguish boundaries and measure the parameters of unknown objects against the background of external natural or artificial interference and noise. These methods have their own advantages and disadvantages, which do not always coincide. Therefore, it is of theoretical and practical interest to use them jointly, multifunctionally, or integrationally to identify objects against the background of external natural or deliberate interference and noise. When applying multifunctional methods for detecting, recognizing, distinguishing borders and measuring parameters of noisy, low-contrast images of objects against the background of external natural or artificial interference and noise. Digital processing of objects is mainly used now, which can be defined as a process during which an image is: modified to obtain a new one, which will be more convenient for research by a computer, or by the human eye; it is transformed into a certain set of characteristics and parameters visible and related to the observation area that are automatically analyzed by the computer, or directly presented to a person, taking into account pre-established criteria for developing a final conclusion about the studied object. Typically, the result of digital processing of the received signals is a new image that can be easily converted to analog form and directly observed on a computer display.

Introduction. A hardware basis of modern Advanced Driver Assistance Systems (ADAS) consists of millimeterrange radars, characterized by a relatively short range (meters – tens of meters). At the same time, improving of traffic safety requires to increase the range at least to several hundred meters. The one way to achieve such values is to increase wavelength of a probing signal, to use the centimeter range of wavelengths, for example. The paper represents a detailed description of main steps of signal processing algorithm in the model of the ADAS low-power centimeter range radar, which provides fast-moving objects speed and range definition.Aim. Development of an algorithm for estimating the range and the speed of targets by an autocorrelation radar with a wide-band continuous linear frequency modulation (linear FM) signal in order to increase the rate of the ADAS system estimates formation.Materials and methods. The proposed algorithm is based on the methods of primary and secondary digital processing of radar signals. The model of a centimeter-range autocorrelation radar with a broadband continuous linear FM probing signal was used for practical researches. MATLAB software was used to process the received signal samples.Results. The algorithm has been developed to determine the speed and the range of fast-moving objects in conditions when their movement during the evaluation interval significantly exceeds the radar range resolution. The use of simplified Kalman filtering for inter-period secondary signal processing allowed to increase significantly the stability of the algorithm. In a full-scale experiment using the low-power radar model with continuous radiation of the centimeter range, it was shown that a stable assessment of a real car speed and range was provided at a distance of at least about one kilometer.Conclusion. The results of the field experiment make it possible to draw conclusions that the proposed algorithm is highly robust even in the absence of inter-period secondary processing. Its usage allows one to improve the stability of the algorithm without considerable additional computational costs. It is possible because near-linear dynamics of the observation object and of the radar carrier makes it sufficient to use a simplified implementation of Kalman filter in the form α-β-algorithm.

The article presents the tasks, characteristic features, tactical and technical characteristics, the possible location and scope of the near-airfield meteorological radar complex. The analysis is made of the comparison of meteorological radar data from the near-airfield meteorological radar complex with reliable sources of meteorological information obtained during preliminary, acceptance, certification tests. The features of carrying out during the validation tests of meteorological radar data of the near-airfield meteorological radar complex are described, namely: dangerous meteorological phenomena (showers of different intensities, thunderstorms with a probability of 30-70%, 71-90%, > 90%, hail of varying degrees of intensity, squall of different intensities), velocity and direction of movement of cloud formations, vector velocity field. Examples of comparing the data of the near-airfield meteorological radar complex with data from a priori reliable sources of information are shown in the form of maps, graphs and tables. It is shown that the data of the near-airfield meteorological radar complex were obtained during testing and certification covering the warm and cold periods of the year, the sample size is statistically significant (except for the sample to assess the vector velocity field from data of aircraft and radar due to the spatial-temporal features comparing data from the two indicated information sources). It was established that the near-airfield meteorological radar complex provides acceptable in accordance with the requirements the construction quality of meteorological phenomena maps, the vector velocity field and the estimation of the cloud formations movement vector. The article illustrates the results of the statistical analysis of the data of the near-airfield meteorological radar complex, obtained personally by the author of the article. Analysis of meteorological data of the near-airfield meteorological radar complex was carried out with the aim of further exploitation of the near-airfield meteorological radar complex.

Introduction. Remote monitoring of layered underlying surfaces is an urgent task. To assess the performance of new algorithms for processing the radar signal reflected from the surfaces, full-scale tests are required. As their carrying out demands big expenses, simulation modeling is actual. There are many methods of estimating an electromagnetic field (EMF) scattered by the earth's surface. However, there are no proven methods and algorithms for engineering calculation of the reflected radio signal in the conditions of this problem.Aim. The aim is to develop and to verify a software model to simulate the reflected multilayer extended structure of the radio signal received on board the aircraft.Materials and methods. The core of the model was based on high-frequency electrodynamics' methods, which allowed rapid calculation for large areas of targets with any number of layers. Simulation was produced using the MATLAB software package. The developed simulation model represented the result in the form of the normalized radar cross-section (RCS) of the multilayer structure. Since the layered structure had rough boundaries, the model provided triangulation of the boundaries of the volume-distributed object. The resulting EMF was calculated using the superposition principle. Each partial EMF value on the facet was calculated taking into account the phase and the polarization of the locally incident EMF.Results. In the paper the comparison of simulation results with theoretical calculations for the normalized RCS of a two-layer structure (difference is less than 10 percent) was presented. Verification for the coefficient of variation of the envelope of the reflected radio signal from the depth of groundwater (critical error was 7 percent) was performed. RCS modeling of the absorbing layer with different degrees of roughness of the layer boundaries was carried out. The upper boundary roughness (for maximal height deviation 0.1 m) affected on specific EPR more than lower boundary. It manifested itself in decreasing of RCS down to 30 dB.Conclusion. The developed model is intended to reduce expenses for designing synthesis of subsurface imaging systems with comparison of scheme "model of device development – field tests – completion – etc". The model is designed to verify the new signal processing algorithms for subsurface radar.

Introduction. Modern air targets, particularly drones, are becoming less noticeable, while their manoeuvrability continues to improve. Trajectory processing algorithms have also been improved in order to provide for effective tracking of highly manoeuvring targets. The accuracy of filtering trajectory parameters is largely determined by the reliability of radar information. This has also required an enhanced role for strobe algorithms and the need to increase the effectiveness of strobe radar marks.Aim. To develop and investigate the efficiency of a trajectory strobe algorithm based on the target motion model in a high-speed coordinate system associated with the direction of the target motion and involving the formation of a strobe in the form of a truncated elliptical sector.Materials and methods. The study considered the target motion model in the body-fixed frame. This model was taken as the basis for new trajectory filtering algorithms based on Kalman filtering. Existing methods for strobing radar marks of the target were considered and a new approach based on filtering in the body-fixed frame proposed. The new algorithm assumes the formation of a strobe in the form of a truncated elliptical sector. This form corresponds to the most probable location of the marks of the tracked target. The effectiveness of the proposed solutions is confirmed by the results of mathematical modelling carried out using MATLAB.Results. The study produced analytical expressions for the motion model, recurrent filtering and strobe algorithm in the body-fixed frame. A comparative analysis of tracking effectiveness with the same volumes of the elliptical and proposed strobes was performed. It was established that the algorithm with strobe formation in the shape of a truncated elliptical sector provides for longer target tracking up to the time of the first loss of the mark for speed and highly manoeuvring targets, when compared to the elliptical strobe algorithm. In addition, the average duration of sector strobe tracking does not in practice depend on the initial speed of the target and provides greater accuracy for small measurement error values (less than 50 m) of the coordinates than in comparison with the elliptical one. Conclusion. The described results were achieved by the ability of the strobe in the body-fixed frame to adapt to the direction of motion and target manoeuvring, allowing high-quality target tracking within a larger speed range. Such strobe formation will also reduce the likelihood of skip-ping radar marks from the tracked target and will reduce the number of false marks belonging to other trajectories inside the strobe.

Using the method of synthesis of the information model at the automated workstation of the air traffic control dispatcher, a fragment of the user interface at the automated workstation of the radar control dispatcher of the Minsk district control center was synthesized, which allows to simulate the stages of the dispatcher's activity in the automated air traffic control system at the modern level of air traffic intensity. The verification of the adequacy and effectiveness of the synthesized user interface fragment was carried out directly with the participation of experts and specialists with experience in such systems. The adequacy of the synthesized user interface fragment was evaluated using a known consent criterion. The evaluation of the efficiency of the synthesized fragment of the user interface of the environment at the dispatcher's automated workstation was carried out under conditions of high air traffic intensity, which force the radar control dispatcher to control in critical mode of operation. Shows the advantage of a synthesized user interface fragment over an existing user interface in terms of time and accuracy. In general, the synthesized user interface fragment exceeds the existing one by about thirty percent. The synthesized user interface fragment noted the more stable activities of the subjects, as well as their better learning capability compared to the existing user interface. The developed experiment scheme allows to carry out research of engineering and psychological factors in human-machine systems of special purpose, including analysis of user interfaces at automated workstations of dispatching personnel in existing automated systems of air traffic control for their assessment and further improvement.