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The idea of improving the methods of processing the received radio signals used in radio communication and radiolocation systems is considered. It is proposed to consider the radio signal as a noise-resistant code with repetition of its periods (symbols), each of which carries the same information about the value of its amplitude and initial phase. The possibility of realization of coherent reception of radio signals with amplitude or biphasic discrete modulation under the influence of powerful noise on them by their most "reliable" (suitable for calculations) fragments, determined by the values of samples, received at moments when the amplitude of a received signal shall be equal to zero (samples correspond to the value of the noise component – point A) or be maximum – point E (the phase of signals shifted with respect to the phase of noise, by π/2 or 3π/4). The considered approach on processing of a mix of a signal and noise allows to define some varieties of "reliable" fragments (at difference of phases of noise and a signal on π/2 or 3π/4, at a match of zero values of signals and noise, at difference of phases of noise and a signal on the value smaller, than ±π/24) on values of samples in points A and E, and also to exclude from consideration fragments, decision on which often is erroneous. The possibility of obtaining an additional estimation ∆ of the quality of the decision on a fragment of a discrete signal (BPSK), with already calculated its average value SСР on the set of its fragments, which allows to select the best or several best fragments for the decision on the received signal is shown. Fragments with a difference of noise and signal phases on the value smaller than ±π/24 occur most often from all considered variants and allow to distinguish with high accuracy the initial phases of opposite signals (BPSK). To solve the problem, we used all possible temporal representations of fragments of signal, noise and a mixture of signal and noise, mathematical models and formulas of the theory of circuits and signals.

The timely discovery of existing threats in the airspace is a permanent concern of the relevant military powers of this century and sensor networks have been developed in this regard, arranged over very large geographical areas in order to achieve a permanent and continuous surveillance of the areas of interest. Research conducted by the scientific community has demonstrated the potential of bistatic (passive) radar as a means of surveillance, the efforts focusing on improving receiver parameters and signal processing algorithms. An important role in these scientific approaches is played by the geodetic distance estimation methods, as well as by the diversification of technical solutions that provide the necessary support for their application and the establishment of algorithms for refining the data provided.

The article carries out a literature review and investigates the existing methods of determining the coordinates of the location of the acoustic signal source. The advantages and disadvantages of passive and active methods given in the article are highlighted. These methods can be used in aviation,cosmonautics, mechanical engineering and other fields of science and technology, where measurements are used, and are designed to determine the coordinates of the acoustic signal source. Recently, there has been a growing interest in using neural networks to solve various problems and their application in various fields. With the help of artificial neural networks, it is possible to process, analyze and summarize information. The authors of the article have compared the method of determining the coordinates of the location of the acoustic signal source using an artificial neural network with existing methods. In this method, the presence of a signal from the acoustic signal source at the reception points is determined by receiving and registering the signal at spatially separated points with known coordinates and further determining the difference in signal propagation times from the source to the signal reception points. The presence of a signal is determined by the middle of the area of the received signal. The number of signal reception points is set at the training stage of the artificial neural network according to the minimum error criterion in determining the coordinates of the acoustic signal source. The time differences of signal propagation from the source to the signal reception points are determined between all reception points, which are located in an orderly or random manner, and these time differences arefed to the input of a previously trained artificial neural network, at the output of which the coordinates of the acoustic signal source are obtained. The application of this method allows to determine the coordinates of the acoustic signal source without having prior information about the distance to the acoustic signal source or any other characteristics of the object, to determine the coordinates of non-periodic signals, to simplify the process of measuring time intervals and calculating coordinates., У статті проведено літературний огляд і досліджено існуючі методи визначення координат розташування джерела акустичного сигналу. Виокремлено переваги і недоліки наведених у статті пасивних і активних методів. Ці методи можуть знайти застосування в авіації, космонавтиці, машинобудуванні й інших галузях науки та техніки, де використовують вимірювання, і призначені для визначення координат джерела акустичного сигналу. Останнім часом спостерігається тенденція зростання інтересу до використання нейронних мереж для вирішення різних завдань і застосування їх у різних сферах. За допомогою штучних нейронних мереж можна опрацьовувати, аналізувати та узагальнювати інформацію. Авторами статті було порівняно метод визначення координат розташування джерела акустичного сигналу із застосуванням штучної нейронної мережі із вже існуючими методами. У цьому методі визначають наявність сигналу від джерела акустичного сигналу у точках прийому шляхом приймання і реєстрації сигналу у просторово рознесених точках з відомими координатами та подальшого визначення різниці часу поширення сигналів від джерела до точок прийому сигналу. Наявність сигналу визначають за серединою площі прийнятого сигналу. Кількість точок прийому сигналу встановлюють на етапі навчання штучної нейронної мережі за критерієм мінімуму похибки визначення координат джерела акустичного сигналу. Різниці часу поширення сигналів від джерела до точок прийому сигналу визначають між усіма точками прийому, які розташовані впорядковано або випадковим чином, причому ці різниці часу подають на вхід попередньо навченої штучної нейронної мережі, на виході якої отримують координати джерела акустичного сигналу. Застосування цього методу дозволяє визначати координати джерела акустичного сигналу, не маючи при цьому попередньої інформації щодо відстані до джерела акустичного сигналу або будь-яких інших характеристик об’єкта, визначати координати неперіодичних сигналів,спростити процес вимірювання часових інтервалів та обчислення координат.

The systems of short-range radiolocation and multistatic radio holography based on multielement MIMO antenna arrays (AAs) with recirculation of orthogonal signals in the spatial feedback circuits of AA transmitting element–​​target–AA receiving element–AA transmitting element are investigated. The generalized ambiguity function in spatial coordinates for an ensemble of coherent orthogonal sounding signals with allowance for the partial propagation constants of the feedback circuits is obtained. The characteristics of the range, azimuth, and elevation resolution in MIMO retrodirective systems are determined based on the analysis of two-dimensional and one-dimensional sections of the generalized ambiguity function (GAF). For the centimeter wavelength range, the GAF cross sections of the azimuth–elevation and range–elevation are compared with and without recirculation as well as at different ranges to the target. The results show the presence of super-resolution effects in MIMO systems with spatial signal recirculation and a nontrivial dependence of the resolution on the target range.

One of possible directions of increase of efficiency of informative facilities of modern and perspective multichannel anti-aircraft missile systems that have in the composition multifunction radar is examined in the article. Existent methods of management the power resource of multifunction radar does not allow in a complete measure to use possibility of the modern radiolocation stations of anti-aircraft missile systems, including in the mode of exposure of air aims. They, as a rule, envisage the use of even parameters of this mode, id est a selection of identical power resource is on realization of measuring of coordinates of aim and transmission of commands of management a few rockets. Besides the sequence of realization of these operations in time is fixed, that not always allows to decide with the proper efficiency and exactness the tasks put before radar. Thus, unchanging order of functioning of multifunction radar in the real terms of battle work results in the decline of her potential carrying capacity and it can result in admission of aims without a fire by a zenithal rocket complex (anti-aircraft missile systems), and as a result, to non-fulfillment of the put combat mission of anti-aircraft missile systems and it worse to elimination of building protection . Thus, for overcoming of contradictions it is necessary to optimize functioning of necessity to change stopped up in multifunction radar on the stage of planning offers, algorithm of battle work that is unchanging in the loop of work of the station and to use the uninvolved time intervals for realization of other indexes of the mode of discovery. Analytical expressions over are brought for the search of air aims in the set area of zone of finding out the station. Researches over of mean value and standard deviation of errors are brought on the search of air aims in the set area of zone of finding out the station. On results the conducted analysis an optimal sector is to the search of air aim in the set area of zone of exposure of the station, came to the conclusion that programed on the stage of planning to the search of aim in the sector of k degrees for аzimut and k degrees on the corner of place(all k x k of angular directions) occupies more than time and charges of power(sentinels) resources than to search of aim of headlights in the sector of q degrees on an azimuth on q degrees on the corner of place.

Актуальність теми: сфера застосування сучасних БПЛА (безпілотних літальних апаратів) на сьогоднішній день дуже актуальна. Велику кількість БПЛА широко використовують як у цивільному, так і у військовому середовищі, що є важливим джерелом даних для спостереження, картографування та моделювання програм. Моделі постійно модернізуються та вдосконалюються і це дозволяє практично непомітно з повітря збирати інформацію про цікавий для нас об'єкт. Мета проекту: визначення основних технічних параметрів радіолокаційних систем контролю руху БПЛА. Новизна одержаних результатів: розроблена структурна схема радіолокаційної системи з малим радіусом дії, розроблена антенна система для РЛС виявлення БПЛА, спроектрований блок синхронізації роботи елементів радіолокаційної системи. Relevance of the topic: the scope of modern UAVs (unmanned aerial vehicles) is very relevant today. A large number of UAVs are widely used in both civilian and military environments, which is an important source of data for observation, mapping and modeling programs. Models are constantly being modernized and improved, and this allows us to collect information about the object of interest to us almost imperceptibly from the air. The purpose of the project: determination of the main technical parameters of radar control systems of UAVs. Novelty of the obtained results: the structural scheme of the radar system with a small range was developed, the antenna system for the UAV detection radar was developed, the synchronization unit of the radar system elements was designed.

The accuracy of radio radiation source (RRS) coordinates determination in MLAT systems is largely determined by the algorithm used. Traditionally, the MPS use one-step estimates of RRS coordinates obtained by the least squares method (LSM), where differences in measurements of RRS signal reception moments at different receiving stations (RS) are used as input data. This approach ignores some of the information contained in the observations - the moments and period of radio signal emission from RRS. The algorithm of joint filtration of RRS coordinates and time of transmission (ToT) for sampling of sequential observations is presented. The results of modeling of different algorithms for determination of RRS coordinates are presented, and the advantages of the proposed algorithm in comparison with the traditional algorithm based on the TDoA method are shown. Estimation of ToT and its filtration at a known period allows you to get closer to the accuracy provided by Time of Flight (ToF) method, which can not be implemented directly for MLAT systems. This hypothesis was confirmed by modeling with the use of two types of trajectories - circular movement and straight-line movement.

F.I. Peregudov graduated from Tomsk Polytechnic Institute with a degree in Radio Engineering in 1953, then done his postgraduate studies at Tomsk State University and worked at Tomsk Polytechnic University: he was one of the organizers and leaders of the first research projects in the field of radiolocation. In 1961 he organized the Tomsk Design Bureau «Project», in 1966 1970 became Director of the Tomsk Radio Engineering Plant, in 1970–1981 took the position of Deputy Director and Director of the Research Institute of Automation and Electromechanics at Tomsk Institute of Automated Control and Radioelectronics (TIASUR), in 1981–1984 took the lead as Rector of TIASUR. In 1984–1985 he continued his career as Deputy Minister of Higher and Secondary Specialized Education of the Russian Soviet Federative Socialist Republic (RSFSR), in 1985–1990 was appointed the USSR Minister and Deputy Chairman of the USSR State Committee for Higher Education. F.I. Peregudov applied a systematic approach in all areas of his activity. During the times he headed Tomsk Design Bureau «Project» F.I. Peregudov organized the development of passive radar equipment. Working as director of the Tomsk Radio Engineering Plant, he created one of the country's first automated control systems (ACS) for production. During his work at the Research Institute of AEM, he initiated the creation of one of the first territory automated control systems in the country. In 1973, the Research Institute of Automation and Electromechanics was designated as the head organization for the development of Tomsk region automated control system, and F.I. Peregudov becomes its chief designer. He made an appeal to many leading scientists from Tomsk to create the Tomsk region automated control system, on his initiative, a computing center for collective use of the Tomsk regional statistics department was established as an integral part of the Tomsk region automated control system. During his work in Moscow, Felix Ivanovich maintained constant contact with Tomsk. In 1990, he contributed to the opening in Tomsk of the first Science Park in Russia

Weather hazards caused by the vertical air movement are considered. It is stated that the only effective mean for their detection is the weather radar. The methods used for this purpose in modern radiolocation are listed, and the difficulties encountered in their practical implementation are discussed. A new method developed by the authors to detect the zone of local vertical movement of elementary reflectors is proposed. It is based on comparing the energy spectrum width of the output signal in the phase and amplitude detection channels.

Indoor localization is becoming increasingly important but is not yet widespread because installing the necessary infrastructure is often time-consuming and labor-intensive, which drives up the price. This paper presents an automated indoor localization system that combines all the necessary components to realize low-cost Bluetooth localization with the least data acquisition and network configuration overhead. The proposed system incorporates a sophisticated visual-inertial localization algorithm for a fully automated collection of Bluetooth signal strength data. A suitable collection of measurements can be quickly and easily performed, clearly defining which part of the space is not yet well covered by measurements. The obtained measurements, which can also be collected via the crowdsourcing approach, are used within a constrained nonlinear optimization algorithm. The latter is implemented on a smartphone and allows the online determination of the beacons’ locations and the construction of path loss models, which are validated in real-time using the particle swarm localization algorithm. The proposed system represents an advanced innovation as the application user can quickly find out when there are enough data collected for the expected radiolocation accuracy. In this way, radiolocation becomes much less time-consuming and labor-intensive as the configuration time is reduced by more than half. The experiment results show that the proposed system achieves a good trade-off in terms of network setup complexity and localization accuracy. The developed system for automated data acquisition and online modeling on a smartphone has proved to be very useful, as it can significantly simplify and speed up the installation of the Bluetooth network, especially in wide-area facilities.

Introduction: Location of weather surveillance radars near settlements, in residential areas and on airport premises makes it important to ensure safe levels of electromagnetic fields when operating these radio transmitters. Electromagnetic fields maximum permissible levels for weather radars developed in the 1980s are outdated. Our objective was to analyze modern weather surveillance radars to develop proposals for improvement of radar-generated radiofrequency field monitoring. Materials and methods: We studied trends in meteorological radiolocation and technical characteristics of modern weather radars for atmospheric sensing and weather alerts, analyzed regulations for electromagnetic fields measurements and hygienic assessment, and measured radiofrequency fields produced by weather radar antennas in open areas and at workplaces of operators. Results: We established that modern types of weather radars used in upper-air sensing systems and storm warning networks differ significantly in terms of technical characteristics and operating modes from previous generations. Developed in the 1980s, current hygienic standards for human exposures to radiofrequency fields from weather radar antennas are obsolete. Conclusions: It is essential to develop an up-to-date regulatory and method document specifying estimation and instrumental monitoring of electromagnetic fields levels generated by weather radars and measuring instruments for monitoring of pulse-modulated electromagnetic radiation.

Recently, the technology has evolved towards artificial intelligence world which include IoT (Internet of Things) and IoE (Internet of Everything) as communication between machines or between devices is possible. The development of these systems today requires electronic components capable of generating higher power and frequency levels, which is why new technologies have emerged to meet these needs, GaN HEMT technology. It has attracted a lot of attention for microwave power and high temperature applications. More recently, this technology has become a great interest to the international scientific community for the realization of low noise amplifiers which are the main components of wireless communication systems. In this paper, we modeled an LNA amplifier based on HEMT GaN transistors. This amplifier is unconditionally stable in the X-band (8–12) GHz with a gain of 38 dB, a noise factor does not exceed 2.4 dB and lower input and output reflection coefficients (S11, S22). at -14 dB and − 8 dB respectively. The designed amplifier can be integrated into radar systems, space communications systems and civilian-military radiolocation systems.

The features of the functioning of coastal radar information support, monitoring and control of the movement of marine vessels in the cramped conditions of navigation are examined and analyzed. The general issues and features of the optimization of digital processing of coordinate information in the near-radar sensing of extended marine objects under the influence of passive interference caused by the presence of the underlying sea surface and hydrometeorological formation in the form of rainfall are formulated and analyzed. Simple and effective digital algorithms have been developed for determining the azimuthal range-finding coordinates of extended objects from selected single and dispersed binary signal groups belonging to an extended radar object. The coordinates of the conditional geometric center, determined in accordance with the developed method, do not contain errors associated with the presence of a jib-trace. The results obtained by estimating the amount of mixing of the object when it moves along the channel are within the range of the real-expected values ΔD ≈ 15 meters. The developed method and its practical implementation are quite simple and effective in providing information support to the skipper in the process of escorting the vessel along the channel. Results fulfilled research in future will use in solving problem of determining the coordinates of the location of extended maritime object, as well as in the solution of similar problems when designing digital radar technics.

This paper proposes a technique for recognizing anthropogenic location objects on an underlying surface that is based on measuring the complete polarization scattering matrix (PSM) of a radiolocation scene. The intelligent analysis of a PSM implies the generation of adaptive robust estimates for trends and covariance matrices, as well as reflected non-stationary non-Gaussian signals. Based on the results of the digital computer simulation experiments and field measurements of the radiolocation scene’s PSM, machine learning algorithms for clustering and classifying the elements of an underlying surface and location object are verified. The possibility of using neural network architecture in the form of a support vector machine for real-time implementation of these algorithms is substantiated.

A polyphase (p-phase, where p is a prime number) radiolocation signal that has an area of zero sidelobes in the vicinity of the central peak of the autocorrelation function has been synthesized. It is shown that this signal is a burst of p coherent phase-code-manipulated pulses coded by p-ary D-code complementary sequences. A method of forming a set of p-ary D-code ensembles is proposed for synthesizing this signal. The correlation characteristics of the synthesized signal are considered. A compression algorithm for the signal, which includes a superposed fast Vilenkin–Crestenson–Fourier transform algorithm, is presented.

The article discusses the solution to the problem of increasing the output power and efficiency of devices using high-current relativistic electron flows.

The article presents a measuring system that allows the noise parameters of the receiver of a radiolocation station to be controlled. The existing solutions of the radiolocation pre-search station P18 Laura control unit have been adapted to the system.

The paper describes the application of the optimization method of fuzzy automatic classification in the problem of combining estimates of trajectory measurements in a radar system. By a radiolocation system the author mean an automated hierarchical technical complex that combines, using communication tools, a set of asynchronously functioning radiolocation tools, as well as central and intermediate points that collect, process and issue trajectory radiolocation information. It must be borne in mind that in conditions of tracking tight groups of air targets, with relatively small intervals and distances, it is not always possible to obtain trajectory information of the required quality. The main reason for this is the difficulty in determining the values of the correlation matrices of errors in estimating the parameters of the state vector of air targets. The task becomes more complicated as the number of intermediate processing points increases when it is brought to the final consumer. The main goal of the article is to increase the accuracy of estimates of trajectory measurements in a radiolocation system. The research is done by means of the mathematical tool of fuzz-set theory, namely, by optimizing fuzzy automatic classification. The article demonstrates that using fuzzy automatic classification under a priori parametrical uncertainty in the law of trajectory measurement errors, when determining weight coefficients, can improve the accuracy of estimates in these conditions up to 30 % compared with methods based on the application of the probabilistic approach. The results obtained allow us to justify the prospects of using optimization methods of fuzzy automatic classification in the tasks of processing trajectory information. In addition, the advantage of the proposed method is its low computational complexity and ease of implementation, which is especially important while maintaining a large number of airborne objects.