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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.

The upcoming transition to a new generation of the elements in the ATC system - AZN-B - has set a number of tasks related to confirming the integrity of the data received, and determining their accuracy characteristics. Radar surveillance systems which are used up to now have established a good reputation and the matter of succession is naturally associated with the comparison of these two recording systems data. Discrepancies (differences) in the AZN-B registrations and radar data are an additional source of information related to reliability and accuracy of their measurements. The problem lies in the method of information extraction. The article analyzes the stable features of discrepancy distribution (histograms) probability obtained in the "Air Navigation Research and Development Institute" branch of GosNII GA by analyzing the observations of aircraft operations in Moscow region. The presence of asymmetry in these histograms is supposed to be interpreted as the presence of uncompensated latency in the transmission of data from AZN-B, which is typical for a certain portion of aircraft in the airspace of Russia. The emphasis on the "territorial affiliation" of the effect is due to the fact that we don’t have any information about the works abroad devoted to the phenomenon under discussion. In accordance with the hypothesis stated, a mathematical model of the measurement procedure with the following parameters to be estimated was constructed: the average value of the uncompensated delay and the expected share of aircraft, characterized by this defect. The values of the sought-for parameters were discovered according to the condition of minimum "distance" between the experimental histogram and the corresponding model analytical dependence. The estimates made revealed that about 30% of the aircraft, out of the total observed number, report their coordinates with an additional error of 75 m. at an average.

Monitoring technologies are rapidly developing at present and allow to extract and use non-coordinate information about objects. Noncoordinate information is the information about the type and properties of an object under study. Remote sensing is the main method of solving monitoring problems where special positioning belongs to the radar methods, based on space-time processing of signals and, in particular, on methods of radio polarimetry. It is necessary to have information about the surface in order to solve the monitoring task. The slightest changes in the electrical and physical properties of such areas as salinity, humidity, soil composition, etc. will lead to a change in the basic electrodynamics of the surface, notably its complex dielectric permittivity. The article demonstrates the precise solutions to the problems of radio-waves reflection from a layered surface with various laws of changes of the complex permittivity  in depth. Media with exponential and quadratic laws of variation  for arbitrary angles of incidence of the radio wave on the surface are considered. Precise decision is obtained for layered media with the law of change in the complex permittivity the polynomial and linear characteristics. A similar problem for the parabolic layer is considered separately. The detailed analysis of radio waves reflection from the medium with a matching layer is carried out. The nature of the electromagnetic field inside the transition layer is studied in detail. The article is illustrated by the graphs showing the dependences of an electromagnetic wave reflection coefficient on the layered medium with linear and exponential laws of variation of the complex dielectric constant over depth.

Using features of Doppler frequency and two its derivatives in the filtration problem for radar survey have been considered. Comparative analysis of filtration parameters for different radar survey have been accomplished.

By working out of a radar with the aperture synthesis of the aerial (RAS) of space basing there is a necessity of its debugging and verification at the land conditions. The most difficult verification task is requirement performance on resolution maintenance of RAS on an azimuth. It is caused by the given resolution provided in RAS at an orbit during stable moving in space with a speed about 7,6 km/s. The verification method of maintenance of the demanded linear resolution of RAS on an azimuth in land conditions with turned synthesis of aerial aperture is offered. It operates when RAS is unmoved and objects of resolution are placed at a moving ship.

В статье предлагается подход к анализу возможности возникновения резонанса в системах с вынужденными колебаниями, включая системы, в которых нет автоколебаний и линейного резонанса. Основным классом рассматриваемых систем являются следящие системы, в которых возможно разделение линейной динамической и нелинейной статической частей. В качестве примера рассматривается радиолокационная станция, функционирующая в режиме обнаружения. Методом гармонической линеаризации формируется уравнение для вынужденных колебаний относительно амплитуды, где параметром является частота внешних колебаний. Показывается, что полученное уравнение может быть решено хорошо известными численными методами, например, методом Ньютона. Решение при любой частоте входного сигнала в рабочем диапазоне частот существует, но необязательно единственно. На частотах, для которых существует два решения уравнения, происходит нелинейный резонанс, характеризующийся скачкообразным увеличением или уменьшением амплитуды вынужденных колебаний. При медленном изменении частоты входного сигнала скачек амплитуды вынужденных колебаний происходит практически мгновенно. Приводятся результаты проверки вычисленных параметров нелинейного резонанса методом математического моделирования, подтверждающие правильность выбранного подхода к анализу резонансных свойств нелинейных следящих систем., The article proposes an approach to analyzing the possibility of resonance in systems with forced oscillations, including systems in which there are no self-oscillations and linear resonance. The main class of the systems under consideration is the tracking systems, in which the separation of the linear dynamic and nonlinear static parts is possible. As an example, a radar station operating in the detection mode is considered. The harmonic linearization method is used to form an equation for forced oscillations relative to the amplitude, where the parameter is the frequency of external oscillations. It is shown that the obtained equation can be solved by well-known numerical methods, for example, Newton’s method. There is a solution for any frequency of the input signal in the operating frequency range, but not necessarily the only one. At frequencies for which there are two solutions to the equation, a nonlinear resonance occurs, characterized by an abrupt increase or decrease in the amplitude of forced oscillations. With a slow change in the frequency of the input signal, the jump in the amplitude of the forced oscillations occurs almost instantly. The results of verifi cation of the calculated parameters of nonlinear resonance by the method of mathematical modeling are presented, confi rming the correctness of the chosen approach to the analysis of the resonance properties of nonlinear servo systems., Авиакосмическое приборостроение, Выпуск 9 2021

В статье рассмотрен новый метод измерения доплеровского изменения частоты радиолокационного микроволнового сигнала, отражённого от движущегося объекта, основанный на технологиях радиофотоники. Измеритель доплеровского изменения частоты имеет ту же структуру, что и последовательное радиофотонное звено с фильтрацией и состоит из лазера, блока электрооптических модуляторов, фильтра – волоконной брэгговской решётки и фотодетектора. Блок электрооптических модуляторов в отличие от известных решений на двухпортовом амплитудном модуляторе Маха–Цендера построен на двух субблоках, состоящих из последовательно включённых тандемных однопортовых амплитудного и фазового модуляторов. Такая замена не усложняет структуру указанного блока по числу используемых модуляторов, тем более если она выполнена на интегральных фотонных схемах. Кроме того, при их использовании обеспечивается высокая спектральная чистота обрабатываемых радиосигналов, перенесённых на оптическую несущую, что позволяет повысить точность измерений. Экспериментальные результаты показывают, что измерение доплеровского изменения частоты в диапазоне ± 100 кГц в области зондирующей частоты около 6,5 ГГц может быть реализовано с погрешностью в доли Гц, а погрешность измерения скорости движения объекта составит доли мм/с., Introduction. The Doppler shift (DS) of the microwave echo signal reflected from a moving object is fundamental parameter for determining the radial velocity and has an important role in radar and wireless communications. Besides DS, the direction of movement is also very important, according to which one can judge where the target is moving - towards the observer or vice versa. Microwave signals demanded in radar cover the frequency range from MHz to hundreds of GHz. However, the measurement of DS, implemented with the use of an electronic component base, can't cover such a large frequency range and, moreover, is extremely sensitive to electromagnetic interferences. Thanks to radio-photonic methods, the range and the accuracy of DS measurements are significantly increased. The aim of the work is to present and experimentally prove the new radiophotonic DS measuring tool. Method and experimental technique. There is presented a novel method for measuring the Doppler shift of a radar microwave echo signal reflected from a moving object, based on radio photonics technologies. The DS measuring tool has the same structure as the sequential radio-photon link with filtration and consists of a laser, a block of electro-optical modulators and a filter that is a fiber Bragg grating (FBG), and a photodetector (PD). The block of electro-optical modulators, in contrast to the known solutions based on a two-port Mach-Zehnder amplitude modulator, is built on two sub-units, consisting of tandem one-port amplitude and phase modulators connected in series. Thus, the measuring tool has a very simple structure and low cost, has a wide operating frequency range up to 40 GHz, determined by the bandwidth of the modulators and the FBG filter, wideband or narrowband PD depending on the type of the signal processing at the output, and high operational reliability due to simple procedures of calibrating and managing the temperature regimes of elements, especially if it is made on the basis of integrated photonic circuits. Research findings showed that the measurement of DS in the range ± 100 kHz at the sounding frequency of roughly 6.5 GHz can be implemented with an error of a fraction of a Hz and the error in measuring the velocity of the moving object of fractions of mm/s., ВЕСТНИК ПОВОЛЖСКОГО ГОСУДАРСТВЕННОГО ТЕХНОЛОГИЧЕСКОГО УНИВЕРСИТЕТА. СЕРИЯ: РАДИОТЕХНИЧЕСКИЕ И ИНФОКОММУНИКАЦИОННЫЕ СИСТЕМЫ, Выпуск 2 (50) 2021, Pages 63-75

Данная работа посвящена предоставлению метода установки локатора на самолет для определения местоположения Ð²Ñ‹ÑÐ¾ÐºÐ¾Ð²Ð¾Ð»ÑŒÑ‚Ð½Ñ‹Ñ Ð»Ð¸Ð½Ð¸Ð¹ для быстрого и точного определения местоположения Ð²Ñ‹ÑÐ¾ÐºÐ¾Ð²Ð¾Ð»ÑŒÑ‚Ð½Ñ‹Ñ Ð»Ð¸Ð½Ð¸Ð¹, снижения Ñ‚Ð°ÐºÐ¸Ñ Ð¿Ð¾Ñ‚ÐµÑ€ÑŒ и предотвращения потери ресурсов. Самолеты ограничены климатическими условиями во время полета, и различные авиационные происшествия могут быть вызваны влиянием ÐºÐ»Ð¸Ð¼Ð°Ñ‚Ð¸Ñ‡ÐµÑÐºÐ¸Ñ ÑƒÑÐ»Ð¾Ð²Ð¸Ð¹, Ñ‚Ð°ÐºÐ¸Ñ ÐºÐ°Ðº осадки, пыльные бури и смог. Среди Ñ€Ð°Ð·Ð»Ð¸Ñ‡Ð½Ñ‹Ñ Ð¿Ñ€ÐµÐ¿ÑÑ‚ÑÑ‚Ð²Ð¸Ð¹, Ð²ÐµÐ´ÑƒÑ‰Ð¸Ñ Ðº авиационным происшествиям, высоковольтные линии являются наиболее опасными. В соответствии с основными принципами работы обычного радара, эта работа выполняет серию Ð¸Ð½Ñ‚ÐµÐ³Ñ€Ð°Ð»ÑŒÐ½Ñ‹Ñ Ð²Ñ‹Ñ‡Ð¸ÑÐ»ÐµÐ½Ð¸Ð¹ и, наконец, получает формулу для отражения поля параллельной поляризации и формулу для отражения поля вертикальной поляризации. И изучили соотношение ÑÑ‚Ð¸Ñ Ð¿Ð¾Ð»ÐµÐ¹, чтобы показать разницу между отражениями от Ð´Ð»Ð¸Ð½Ð½Ñ‹Ñ Ð¿Ñ€Ð¾Ð²Ð¾Ð´Ð¾Ð² Ð²Ñ‹ÑÐ¾ÐºÐ¾Ð²Ð¾Ð»ÑŒÑ‚Ð½Ñ‹Ñ Ð»Ð¸Ð½Ð¸Ð¹ электропередач и отражениями от Ð´Ñ€ÑƒÐ³Ð¸Ñ Ð¾Ð±ÑŠÐµÐºÑ‚Ð¾Ð² (земли, полей, лесов, океанов, рек и т. Д.) и как использовать практически это отличие., The given work is devoted to providing a method for installing a locator on an aircraft to locate high-voltage lines to quickly and accurately locate high-voltage lines, reduce such losses and prevent loss of resources. Aircraft are limited by climatic conditions during flight, and various accidents can be caused by the influence of climatic conditions. such as precipitation, dust storms and smog. Among the various obstacles leading to accidents, high voltage lines are the most dangerous. According to the basic principles of conventional radar, this work performs a series of integral calculations and finally derives a formula for reflecting a parallel polarization field and a formula for reflecting a vertical polarization field. And studied the relationship of these fields to show the difference between reflections from long wires of high-voltage power lines and reflections from other objects (land, fields, forests, oceans, rivers, etc.) and how to use this difference in practice.

Показаны особенности применения методов искусственного интеллекта в современных радиолокационных комплексах (РЛК) мониторинга для организации превентивного технического обслуживания. Приведена структурно-функциональная схема интеллектуальной системы поддержки функциональных характеристик РЛК. Представлены экспериментальные оценки точности прогнозирования излучаемой мощности РЛК по данным диагностического контроля., Purpose. This work is devoted to a description of an intelligent support system (ICP) of the functional characteristics of radar systems operating in heat-stressed modes. The purpose of the work is to simulate the operation of the failure prediction module based on the data on the operation of the critical components of the radar. Methodology. Failure prediction based on block temperature data was performed using supervised machine learning methods, including regression methods. The highest quality parameters of the forecasting model (horizon - accuracy) were achieved when training the model using the gradient boosting method, which allows organizing continuous additional training of the forecasting model during the operation of the radar by forming a training sample consisting of a data flow about the technical state. Findings. A structural and functional diagram of the ICP has been developed and a description of the operation of its components is given. The error (20%) and the horizon (20 min.) of the prediction of failures obtained during the experiments are sufficient for the staff serving the radar to take the necessary measures and prevent a critical decrease in the functional characteristics of the product. Originality/value. The introduction of ISP will allow realizing the maximum functional capabilities of the radar, taking into account the forecast of their change, as well as making an operational report to the command post of the radar on the reasons for the decrease in functional readiness according to the pop-up tips about the faulty element and the degree of its influence on the functional characteristics., Вычислительные технологии, Выпуск 6 2021, Pages 95-103

Introduction. The modern approach for ensuring marine activities of necessary quality related to the assessment of current information on the state of the ocean environment in Russia is clearly insufficient. The development of operational methods and instruments of observation, as well as the assessment of the state of the ocean and its forecast naturally determine such an approach. Therefore, the development of the concept, tools and methods of obtaining data is an urgent task of the operational Oceanography formation.Objective. The objective of the paper is to con-sider the concept of ocean surface monitoring using short-wave surface wave radar.Methods and materials. The paper presents a number of specific Oceanologic examples that require operational monitoring of the state of coastal waters of the oceans and individual regions. Also, it describes observational systems used in other countries. The paper pays special attention for the development of radar sensing of surface waters, carried out in our country occasionally. The resonant nature of the reflections gives the opportunity to obtain maps of high-precision measurements of surface currents and wave characteristics on the long-range area in real time. The paper notes difficulties of the experiments implementation and the results interpretation, shows the insistent issues for the establishment of the ocean surface operational monitoring, and gives the approaches for solvation of the existing problems. The paper formulates the main task of the world ocean parameters forecast for ensuring of the sea transport safety from natural and anthropogenic threats, as well as formulates the problems solution of effective nature management.Results. The paper shows that the optimal means of natural data acquisition is the creation of an observation network of coastal HF radars, which enables to assess surface currents and wave characteristics, as well as to solve the problem of monitoring. It is Important to develop an adequate coastal model and correlate its parameters with experimental data. The adaptive modeling and monitoring by modern technical means can overcome inadequacy of physical models to specific natural conditions can.Conclusion. By assimilation in hydrodynamic and wave models, these data become applicable in spatial mapping of hydrophysical inhomogeneities of the water layer, sound velocity, and underwater acoustic noise.

Aerodrome-enroute surveillance radar systems (ARSR) of civil aviation are designed for detection of aerial objects and determination of their range and movement parameters. Meanwhile, the reflector-type antennas are still the main type of_used antenna systems. Radars (ARSR) have, as a rule, antennas with a bidirectional beam, structurally reflector-type antenna is made in the form of a truss welded structure. The use of active phased antenna arrays (APAR) is a promising direction of radars (ARSR) development. Radars (ARSR) based on the phased antenna arrays can significantly improve such critical tactical and technical criteria as: the accuracy of the coordinates determination, the number of simultaneously followed targets. However, the use of APAR does not solve one of the main problems - the presence of a support-rotary device in the radar (ARSR). The principal necessity of a support-rotary device leads to the need of the use of movable joints of feeder lines, which, with a significant number of antenna elements used in the PAR, significantly reduces the potential time before failure. It seems promising to use in the radar antenna systems based on several stationary multi-beam dual-reflector antennas made by axially asymmetric scheme. Methodology of estimation of aberrations of a dual-reflector sensimetrics antenna based on a polynomial expansion of the eikonal function in the plane of the aperture of the main reflector is proposed in the article. Analytical expressions of the functions of display and rotation of the scanning plane of a dual-reflector axially asymmetric antenna with arbitrary parameters, designed based on clippings from centrally symmetric surfaces of rotation of the second order, are obtained. It is shown that the aplanatic antennas lose their scanning features during the transition to the axially asymmetric variant.

The disadvantage of (RLI) radar images obtained with a single-channel radar station is the presence of speckle that leads to intensity flashes increasing the number of false alarms when detecting point targets. Therefore, the detection and target distinguishing by their reflective capability (using the energy characteristics of the signal) is not effective enough. In polarimetric radar stations the formation of each image element is carried out by the output signals of four receiving channels. Joint processing of these signals allows minimizing speckle without reducing the resolution capability. The paper presents the results of the computer simulation of the suppression methods of the image speckle obtained in the polarized radar stations with the synthesized antenna aperture. The first one uses the norm of the backscattering matrix as a parameter of the intensity of the reflected signal resolution from the i-th element. The incoherent addition of the intensities obtained by sequential overview of the space with several rays is carried out in the second one. Both of these methods can be applied together. The block diagram of such processing for one strip of range is given. The computer simulation of the three-rayed suppression method of the image speckle obtained in the radar stations with the synthesized antenna aperture is carried out. As a model of the reflecting surface a random diffraction grating formed by a set of independent reflectors located at the nodes of a regular rectangular grid with a step of 1 m is chosen. In this connection the image of the grating is formed as an incoherent sum of three images obtained at different angles. The results show that the speckle effect reduces even at angular changes of the order of degree units.

Nowadays the interest in search of ways of improving the efficiency of small radar cross-section aerial objects detection and localization rises against the background of widespread use of light and unmanned aerial vehi-cles. As a result, researchers pay attention to radar systems (RS) with continuous linear frequency modulation (linear FM) signal. The use of such signals gives the measurable opportunity to reduce radar system peak-speech power and to cut the cost and weightsize parameters of the RS. The paper observes low-power ground based radar implementation prospects for purposes of detection and estimation of motion rates of small-sized aerial objects. The proposed algorithm of radar signals processing enables to simplify the detection of such tar-gets. The paper reveals the structure and defines the steps of the algorithm. The fundamental for the algorithm under consideration is the method of the range-Doppler image composition of the scanned area using digital signal processing. The paper presents the results of the algorithm operation in the low-power RS of C-band radar, obtained by processing of quadrotor echo-signals during the real experiment. The results show successful solvation of the applied problem of detection and tracking on the small-sized aerial object with the radar cross-section equal to less than 0.5 m2 and the spectrum of secondary radiation characterized by the expressed multimodality. The results of the experiment validate the application of the algorithm and demonstrate the possibility of the algorithm implementation in design of portable RS and automated target acquisition centers for detecting and tracking of the small-sized aerial targets (both, single as multi agent) with the information display on operator control panel.

The fine structure and conditions for the occurrence of radar reflections from a cloudless atmosphere in various meteorological conditions and at different times of the year are considered. The few research results in the millimeter wavelength range determine the importance and relevance of the tasks in this area. The results of field measurements carried out using a radarof 8 mm wavelength range at different times of the year under various weather conditions are presented. The possibilities of the developed software for processing and analyzing the data are considered. The obtained data can be used in the design of all-weather small-sized weather radars for various purposes. The parameters of pulse Doppler radars of 8 mm wavelength range for measuring wind profiles in a wide range of weather conditions are presented. Sensing modes, methods for processing and accumulating data using software, as well as the form for presenting the results are indicated. The technique of wind profile recovery in the directions of sounding is considered. The data on radar reflectivity in a clear sky in various meteorological situations are given. Separately, the features of the structure of the Doppler spectra in the millimeter wavelength range when reflected from the clear sky are considered.

ObjectivesThe aim of the study is to develop a methodology for identifyingaircraft by the deflections of an electromagnetic radar beam by a heated jet engine. MethodsAtoms of the crystal lattice of the metallic parts of the operating jet engine will be in a state of chaotic Brownian motion due to heating. The electromagnetic beam, falling on these atoms, will change its frequency in accordance with the Doppler effect, by means of which the spectral electromagnetic radiation component will expand in direct proportion to the magnitude of the engine temperature. When determining the width of the spectral line of the direction-finding radio emission, it is possible to accurately identify the temperature of the aircraft in order to avoid false targets.ResultsWhen locating aircraft having a working jet engine, it is possible not only to determine the coordinates of the target, but also to identify the heated engine. Due to the use of high-precision methods for identifying heated sections, the direction-finding targets may be classified, the spatial orientation of both the aircraft itself and its control planes to be determinedand the direction of the thrust vector control of the jet engine calculated.ConclusionThe application of an innovative technique for direction-finding air targets will allow the radar targets to be identified with high accuracy against the background of active and passive interferences. In addition, when analysing the information on the magnitude and direction of the jet engine thrust and the position of the aircraft controls, it is possible to determine not only the coordinates of the direction-finding object, but also to proactively identify the manoeuvres to be performed.

At present, multilateration systems are becoming increasingly important in air traffic control. This is due to their significant advantages in compare with secondary surveillance radar complexes. This article solves the problem of synthesizing an algorithm for object location estimation for multilateration system operating in passive mode. The synthesized algorithm is a combination of a procedure, the result of which is a rough estimate of the observed object coordinates, and an iterative algorithm specifying the resulting solution. The rough estimate is the result of solving a linear system of equations. The iterative refinement procedure is based on the linearization of the observational equations and does not require a large number of iterations. The paper provides a comparative statistical analysis of the proposed algorithm and the known Bancroft algorithm. For an objective analysis of two algorithms, the paper derives the Cramer-Rao boundary for the correlation matrix of estimates of the observed object coordinates, which makes it possible to determine the potential accuracy of the solution of the problem. It is shown that both algorithms allow obtaining estimates, the accuracy of which is close to the potentially achievable accuracy of the object location estimate. In contrast to the Bancroft algorithm, the rough estimate of the object location is unambiguous. This virtue reduces the total amount of computations during the algorithm implementation and reduces the probability of anomalous errors.

Often, the monitoring systems solution of remote sensing problems, recognition (classification, discrimination) of radar objects using radio polarimetry methods is required in real time mode with the display of the current information on the radar monitor. Monitoring systems can be either stationary (more often terrestrial) or mobile (based on various transport vehicles). When designing such systems, along with ensuring the required speed and performance of the computer, it is also important to ensure the unification of the units and assemblies, the reduction of weight and size characteristics, simplification of the tuning, increase of the operational reliability. In this case, the use of blocks of digital information processing is required. When digitally processing polarized signals, it is necessary to convert the input analog signal to digital form, i.e. to sampled by time and frequency and perform level quantization. The peculiarities of the discretization of the radar polarized signal over time are considered in the article. Analytical expressions for the input polarized signal are derived with considering the geometric parameters of the polarization ellipse. Formulas are given for the in-phase and quadrature components of the polarized signal, for a complex signal envelope. It is alleged that quadrature processing of the polarized signal leads to a decrease in the requirements for analog-to-digital conversion chips due to a significant reduction in the sampling frequency. After the transformations presented in the article, electronic components, which are already in production by Russian companies in the radio electronic industry, can be used in monitoring systems. The transformations of a polarized signal in the time domain described in the article lead to certain transformations in the frequency domain. We are talking about converting the two-side signal spectrum into a one-side spectrum with its transfer to the video frequency region. Such a conversion helps to reduce the sampling rate from gigahertz to megahertz. Analytic expressions in the time domain are accompanied in the article by a graphic interpretation of the signal spectra in the frequency domain. A scheme for demodulating the in-phase and quadrature components of the polarized signal is given. Functional features of filtering units in the scheme are described, the attention of the designers of the digital signal processing systems to the requirements of the Kotel'nikov's sampling theorem is emphasized.

Обсуждаются проблемы использования роботизированных комплексов для обследования и регистрации следов цунами в труднодоступных местах. Приводится описание такого комплекса с хорошими эксплуатационными характеристиками, разработанного в Нижегородском государственном техническом университете им. Р.Е. Алексеева. Представлено решение, позволяющее доукомплектовать автономный мобильный робототехнический комплекс сенсором собственного производства и повысить его проходимость. Предложен способ построения антенной решетки, позволяющий достичь оптимальных характеристик в отношении максимальной дальности обнаружения и углового разрешения. Этот результат достигается за счет того, что вся геометрическая апертура антенны «заполнена» элементами (столбцами) с шагом в половину длины волны. При этом размещение приемных подрешеток на краях подложки формирует наибольшую апертуру в условиях решаемой задачи и позволяет использовать классический метод диаграммообразования при работе в дальней зоне. Рассмотрен пример построения антенной решетки, обеспечивающий формирование лучей шириной 5° в секторе углов дальней зоны. Применение предложенного решения позволяет расширить зону обнаружения объектов., The problems of using robotic systems for survey and registration of tsunami tracks in hard-to-reach places are discussed in this paper. A description of such a complex with good operational characteristics, developed at the Nizhny Novgorod State Technical University n. a. R.E. Alekseeva. A solution that allows to equip an autonomous mobile robotic complex with a sensor of its own production and increase its cross-country abilityis presented. A method for constructing an antenna array is proposed, which allows achieving optimal characteristics in terms of maximum detection range and angular resolution. This result is achieved since the entire geometric aperture of the antenna is «filled» with elements (columns) with a step of half the wavelength. In this case, the placement of the receiving sublattices at the edges of the substrate forms the largest aperture under the conditions of the problem being solved and allows the use of the classical method of diagramming when working in the far zone. An example of constructing an antenna array providing the formation of beams with a width of 5° in the sector of the far-fi eld angles is considered. Application of the proposed solution allows to expand the detection area., Экологические системы и приборы, Выпуск 11 2020

Поступила : 01.11.2020. Принята в печать : 23.11.2020. Received: 01.11.2020. Accepted: 23.11.2020. Рассматриваются и сравниваются параметры антенных систем радиолокаторов, построенных по традиционной схеме с фазовращателями как в антенной решетке передатчика, так и в антенной решетке приемника с радиолокатором, в котором обработка сигнала выполняется только на приемной стороне. Во втором случае на излучающую систему передатчика накладывается дополнительное требование ортогональности излучаемых сигналов. Сравниваются характеристики радиолокатора с тремя передающими антеннами и четырьмя приемными. Рассматриваются два варианта формирования виртуальной антенной системы. В первом случае анализируется излучение линейной регулярной антенной решетки, во втором – прореженной, но с тем же числом излучателей. Показано, что во втором случае можно реализовать радар с лучшим угловым разрешением. Рассмотрены особенности применения радаров в качестве сенсоров систем безопасности автомобиля с широкоугольным обзором. Отмечена возможность ложного захвата цели. Предложен способ однозначной пеленгации. The parameters of radar antenna systems constructed according to the traditional scheme with phase shifters inserted both in the transmitting and receiving antenna array with the radar in which signal processing is performed only on the receiving side are considered and compared in the paper. In the second case, an additional requirement of orthogonality of the radiated signals is imposed on the radiating system of the transmitter. The characteristics of the radar with three transmitters and four receivers are compared. Two variants of forming a virtual antenna array are considered. In the first case, the radiation of the linear regular antenna array is analyzed, in the second case the thinned one, but with the same number of emitters. We demonstrate that in the second case, it is possible to implement the radar with a better angular resolution. The features of using the radar as a short-range radar for vehicle security systems with a wide-angle view are elaborated. The possibility of false capture of the target is noted. The authors of the research suggest the unambiguous direction finding method. Работа выполнена при финансовой поддержке Министерства науки и высшего образования Российской Федерации в рамках соглашения № 075-11-2019-052 от 13.12.2019 с Научно-производственным объединением автоматики имени академика Н.А. Семихатова (АО «НПО автоматики») по комплексному проекту «Создание высокотехнологичного производства высокочастотного радара, предназначенного для использования в составе интеллектуальных систем помощи водителю, систем автоматического управления беспилотных транспортных средств и систем интеллектуального земледелия» при участии ФГАОУ ВО «Уральский федеральный университет имени первого Президента России Б.Н. Ельцина» (ФГАОУ ВО «УрФУ») в части выполнения научно-исследовательских, опытно-конструкторских и технологических работ. This work was financially supported by the Ministry of Science and Higher Education of the Russian Federation under agreement No. 075-11-2019-052 dated December 13, 2019 with the Scientific and Production Association of automatics named after academician N.A.Semikhatov in the complex project “Creation of a high-tech production of a high-frequency radar intended to be used as a part of intelligent driver assistance systems, automatic control systems for unmanned vehicles and intelligent farming systems” with the participation of the Ural Federal University named after the First President of Russia B.N. Yeltsin in terms of the implementation of research, development and technological work.

Исследуется зондирование снежного покрова методом радарной интерферометрии. Предложена приближенная модель интерферометрического зондирования, основанная на методе малых возмущений. Поле обратного рассеяния рассматривается как когерентная сумма волн, рассеянных на неровностях границ раздела “воздух - снег” и “снег - почва”. Представлены результаты определения водного эквивалента снега с помощью радарной интерферометрии на ровной земной поверхности (равнина) и поверхности с уклонами рельефа (холмисто-гористая местность). Проведена оценка вклада рассеяния от поверхности снега в значения амплитуды и интерферометрической фазы. Выполнен анализ влияния уклонов рельефа на оценку параметров снежного покрова. Приведены результаты численных оценок. Показано, что для местности с уклоном рельефа около 45изменения в интерферометрической фазе относительно ровной поверхности достигают 40%. Однако если склоны сравнительно ровные (менее 10), эти изменения не превышают 10%, The main characteristics of the snow cover determining its impact on the environment are its thickness and the snow water equivalent (SWE). SWE assesses the water content in the snow cover. Radar interferometry is one of the methods for determining SWE. The paper presents the results of snow cover sensing by radar interferometry on both flat Earth’s surface and terrain with relief. A backscattering model taking into account backscattering from the snow surface is proposed in contrast to the existing methods. The backscattering field is considered as a coherent sum of waves scattered on the irregularities of the air - snow and snow - soil interfaces. These interfaces are statistically rough surfaces with random irregularities, whose heights are described by uncorrelated stationary random functions with their mean values, standard deviations, and correlation radii. It is assumed that the irregularities are small compared to the wavelength, their slopes are small, and the conditions for the applicability of the method of small perturbations are satisfied. It is also supposed that roughness does not affect the coherent field according to the Born approximation. The incident and scattered waves are assumed to follow Snell’s law. The coherent waves reflection and transmission coefficients are determined by Fresnel formulas for a flat interface. The contribution of backscattering from the snow surface to the values of the amplitude and interferometric phase is estimated using small perturbation method. It is shown that the relative error of interferometric phase determination due to the influence of the wave scattered by the air - snow boundary does not exceed 8% for the angles of incidence of 20-45and the density of snow 0.2-0.3 g/cm. The approximate relations show the linear dependence between the interferometric phase and SWE. The model is extended to the general case of backscattering from snow cover on the Earth’s surface with relief. The influence of terrain slopes on the interferometric phase is estimated. It is shown that for hilly terrain with slopes of about 45, the relative changes in the interferometric phase could reach 40%. However, if the slopes are relatively flat (less than 10), these changes do not exceed 10%., Вычислительные технологии, Выпуск 4 (25) 2020

Автономные транспортные средства, или, как мы обычно их знаем, автомобили с автоматическим управлением, часто представляются в качестве транспортной технологии будущего. Наконец-то становится возможной возможность управления транспортным средством без вмешательства человека или ручного управления. Первой задачей было бы настроить и впитать существующие технологии в обычном автомобиле, чтобы перевести их на почти ожидаемый автономный автомобиль. Этот переход обычных транспортных средств в автономное транспортное средство путем принятия и реализации различных будущих технологий обсуждается в этом тезисе. Это включает в себя цели автономных транспортных средств и трудности реализации. Диссертация также затрагивает существующие технологии, такие как обнаружение объектов, обнаружение и центрирование полосы движения, планирование пути и сравнение с традиционными методами. Эти подходы затем тестируются в среде моделирования перед применением на реальном солнечном автомобиле Санкт-Петербургского политехнического университета., Autonomous vehicles, or as we usually know them by, self-driving cars, are often presented as the transportation technology of the future. The possibility of a vehicle to drive itself without any human intervention or manual control finally becomes possible. The first challenge would be to customize and imbibe existing technology in a conventional vehicle to translate them to a near expected autonomous car. This transition of conventional vehicles into an autonomous vehicle by adopting and implementing different upcoming technologies is discussed in this thesis. This includes the objectives of autonomous vehicles and the implementation difficulties. The thesis also touches upon the existing technologies such as object detection, lane detection and centering, path planning and comparison with the traditional methods. These approaches are then tested on a simulation environment before applying on the real solar car of Saint-Petersburg Polytechnic University.

Выпускная квалификационная работа посвящена изучению Ñ‚ÐµÑ Ð½Ð¾Ð»Ð¾Ð³Ð¸Ð¸ FMCW радаров миллиметрового диапазона, построению экспериментального стенда, обладающего требуемыми параметрами, соответствующими результатам исследования алгоритма обработки Ñ€Ð°Ð´Ð°Ñ€Ð½Ñ‹Ñ Ð´Ð°Ð½Ð½Ñ‹Ñ . Результатом работы является рабочий стенд, обладающий Ð½ÐµÐ¾Ð±Ñ Ð¾Ð´Ð¸Ð¼Ñ‹Ð¼Ð¸ параметрами сигнала, собирающий и передающий данные для дальнейшей постобработки., The final qualification work is devoted to the studying of FMCW radar technology, building experimental device, with required parameters, corresponding to the research on radar data processing algorithm. Result of this work is an operating unit, capable of capturing and transmitting the data for further post-processing.

Source at https://doi.org/10.21443/1560-9278-2018-21-1-170-181. Licensed CC BY 3.0. Results of observations of variations of temperature, electron concentration and total electron content of the high-latitude region of the ionosphere during its modification by powerful short radio waves of the heating complex EISCAT/Heating (Tromsø, Norway) according to signals of the GLONASS satellites and the incoherent scattering UHF EISCAT radar (Tromsø, Norway) have been provided. The geometry of passes of the GLONASS and GPS satellites for operating conditions of the heating complex in Tromsø has been considered. It has been shown that during the experiments on the EISCAT/Heating complex for the study of the modified structure of the high-latitude ionosphere it is more convenient to use the GLONASS satellites. Parameters of orbits of these satellites allow researching changes of total electron content in the direction along the geomagnetic field line at the place of observation. It has been shown that during heating of the ionosphere by powerful short radio waves its structure is becoming an irregular one. Operation of the heating complex in the mode "switched on – switched off" has caused appearance of wavy variations of total electron content with the periods close to the heating period. The main features of behavior of the total electron content in the case of the continuous heating of the ionosphere in the direction of the magnetic zenith according to the GLONASS satellite are: reduction of total electron content in the central zone of the antenna diagram, i.e. in the direction of the magnetic zenith, and presence of the increased values of total electron content at the edges of the heating zone. According to the incoherent scattering radar the heating of the ionosphere by the powerful short radio wave has created the region of the increased electron temperature and electron concentration along the direction of the magnetic zenith. The behavior of total electron content according to the GLONASS satellite and the radar of incoherent scattering in many respects corresponds each other except the central part. Reasons of the mismatches have been considered. Представлены результаты наблюдений изменения температуры, электронной концентрации и полного электронного содержания высокоширотной области ионосферы во время ее модификации мощным коротковолновым радиоизлучением нагревного комплекса EISCAT/Heating (Тромсё, Норвегия) по данным сигналов спутников ГЛОНАСС и радара некогерентного рассеяния УВЧ ЕИСКАТ (Тромсё, Норвегия). Рассмотрена геометрия пролетов спутников ГЛОНАСС и GPS для условий работы нагревного комплекса в Тромсё. Показано, что во время экспериментов на комплексе EISCAT/Heating для изучения модифицированной структуры высокоширотной ионосферы удобнее использовать спутники ГЛОНАСС. Параметры орбит этих спутников позволяют исследовать изменения полного электронного содержания в направлении вдоль геомагнитной силовой линии в месте наблюдения. Показано, что во время нагрева ионосферы мощной коротковолновой радиоволной ее структура приобретает неоднородный характер. Работа нагревного комплекса в режиме "включено – выключено" вызывает появление волнообразных вариаций полного электронного содержания с периодом, близким к периоду нагрева. Основными особенностями поведения полного электронного содержания при непрерывном нагреве ионосферы в направлении магнитного зенита по данным спутника ГЛОНАСС явились уменьшение полного электронного содержания в центральной зоне диаграммы направленности антенны нагревного комплекса, т. е. в направлении магнитного зенита, и присутствие повышенных значений полного электронного содержания на краях зоны нагрева. По данным радара некогерентного рассеяния во время нагрева ионосферы вблизи направления на магнитный зенит формируется область повышенной электронной температуры и электронной концентрации. Поведение полного электронного содержания по данным спутника ГЛОНАСС и радара некогерентного рассеяния во многом соответствует друг другу, кроме этой области. Высказываются предположения о причинах такого несоответствия.

The basis of modern radar techniques is the direct use of radio-physical data on the power of backscattering. At the same time, the data volume received from the radar allows us to form new estimates and essentially specify classical ones. Significant steps have been made in this direction, using, for example, phase (Doppler) methods. The "modified Rayleigh model" used in radar meteorology to form a scattered field on rarefied medium particles is called the Kerr-Rice model. The main advantage of the Rayleigh model is its simplicity. But it itself contains a deep contradiction, consisting in its logical completion. Based on the statistics study of the first distribution in the rains of varying intensity the authors on a large statistical material have determined the fact of their not Rayleigh form and extreme stability of the latter in relation to natural changes of precipitation intensity. The first distribution is different from the theoretically expected one in the Kerr-Rice model, which makes it possible to use linear-logarithmic detection. It is concluded that the width and the mean of the spectrum of the same signal have the expected dynamics with respect to changes in precipitation intensity and dynamic processes in them. Tables with experimental data are presented. Two main distribution models are considered: lognormal and "logo-gamma-functional". It is concluded that, despite the absence of qualitative differences, the difference in the form of the distributions obtained with different equipment can be a natural consequence of significant discrepancies in the peak power and / or the width of the antenna pattern. The graphs of the first experimental distributions of envelope fluctuations on a linear and semi-logarithmic scale are presented.

The article contains the statistics analyzes of accidents associated with adverse external conditions, including weather conditions, for seven years. On the analysis basis insufficient supply of final consumers meteorologic data is concluded. One of the ways to improve meteorological support of Unified air traffic management system consolidated centers by creating regional centers of processing radar information for conducting environment geophysical monitoring is suggested.

This article describes the main achievements in the development of phased antenna arrays (par) in the past decade. Provides an overview of the most famous systems based on the PAR and PAR based on MMIC technology - PAR in radar stations, PAR to control the laser and optical beams. The existing options for the design of the PAR:ferroelectric antenna array; plasma antenna with electronic scanning; reflective grating on 100-mm semiconductor wafers; wideband antenna arrays with aperture; antenna arrays with digital beam forming.

Объектом исследования в данной работе являются современные методы компьютерного зрения и поиска препятствий. Целью данной работы является исследование возможностей компьютерного зрения и машинного обучения в Ð·Ð°Ð´Ð°Ñ‡Ð°Ñ Ð¾Ð¿Ñ€ÐµÐ´ÐµÐ»ÐµÐ½Ð¸Ñ препятствий и , в частности, при совместном использовании лидара и видеокамеры. Результатом данной работы является алгоритм обработки и комплексирования Ð´Ð°Ð½Ð½Ñ‹Ñ Ð²Ð¸Ð´ÐµÐ¾ÐºÐ°Ð¼ÐµÑ€Ñ‹ и лидара. Результаты данной работы будут являться частью системы автопилотирования железнодорожного состава. Также возможно использование алгоритма на Ð´Ñ€ÑƒÐ³Ð¸Ñ Ð²Ð¸Ð´Ð°Ñ Ñ‚Ñ€Ð°Ð½ÑÐ¿Ð¾Ñ€Ñ‚Ð°., The object of research in this paper are modern methods of computer vision and search for obstacles. The purpose of this work is to study the capabilities of computer vision and machine learning in the problems of determining obstacles and, in particular, when sharing a lidar and a video camera. The result of this work is the algorithm for processing and complexing the data of the video camera and lidar. The results of this work will be part of the train autopilot system. It is also possible to use the algorithm on other modes of transport.

Приведены результаты исследования возможности применения поляриметрических и интерферометрических данных X-иL-диапазонов TanDEM-X и ALOS-2 PALSAR-2 для мониторинга криогенных рельефообразующих процессов полуострова Ямал. Выполнен статистический анализ сезонных изменений интенсивности и параметров поляриметрической Н - А - α -декомпозиции на участках с оползнями, активно растущими и пассивными термоцирками научного полигона Васькины дачи., The article presents the results of the developed methods for thermal-degradation processes detection and monitoring based on the X- and L-bands radar data. The research objects are developing thermocircuits and collapsing slopes in the coastal zone of ten lakes of “Vaskiny Dachi” polygon (Central Yamal, 70∘15′N, 69∘05′E). To detect the formed and active cryogenic formations TanDEM-X and ALOS-2 PALSAR-2 interferometric and polarimetric data (VV, VH) of 2015-2016 were used. The research was carried out in three directions: 1) digital terrain models (DTM) with high resolution construction using differential interferometry methods and the cryogenic formations topographical features identification, temporal changes in DTMs observation; 2) comparative statistical analysis of the total intensity and the polarimetric Н-А-α -decomposition components for cryogenic formations and adjacent stable sites; 3) development of a technique for express detection of such formations on the basis of total intensity and polarimetric Н-А-α -decomposition components images texture. It is established that the intensity, polarimetric characteristics, topography parameters and textures of radar images significantly differ from those for neighbouring stable regions (more than 3 σ ) for active thermocircuits. Intensity variations are most significant, but the localization of cryogenic formations can be limited by the radar survey geometric conditions. For passive thermocircuits, landslides in the coastal zone, deviation of intensity and polarimetric characteristics from background ∼ σ , therefore as an indicator a set of polarimetric Н-А-α -decomposition parameters should be used. Combining parameters α and H can be the basis for express diagnostics of the occurrence and activation of cryogenic processes in the area of the present study., №4(23) (2018)