Currently, there is a need to replace mirror antennas used on mobile communication complexes with phased array antennas, including active ones, with better electrical and mass-dimensional characteristics. The purpose of the work is a theoretical and experimental study of the characteristics of a multi-element strip antenna array for subscriber terminals of satellite communication systems. The above research results have shown that most of the side lobes of the radiation patterns of this multi-element strip antenna array are located in two mutually orthogonal planes, while, for example, in mirror antennas, the side lobes of the bottom are located around the main lobe of the bottom. This, in turn, is an advantage of this multi-element strip antenna array, since the probability of operation of the satellite communication system on the side lobes is reduced. The research results allowed us to conclude that further work is promising in order to create new technical antenna solutions for subscriber satellite communication systems. Further development of the antenna array under consideration is associated with the use of digital diagramming circuits to control the beam of the radiation pattern.

The detection of malware represents a primary concern in contemporary computer security and is therefore imperative for the protection of systems and data integrity. This research presents an innovative approach to comparing diverse input image formats with the objective of identifying the optimal methodology for detecting specific malware-related signatures using convolutional neural networks (CNN), which have been specifically developed by the authors for this purpose. Subsequently, machine code instructions are generated and then converted into four distinct image format options. The four image formats, namely 1xN fixed, 1xN scalable, NxN fixed, and NxN scalable, are subsequently employed for the training of the CNN. The study assesses the formats in question in terms of training time, accuracy, and computational complexity. The results demonstrate that the NxN scalable format exhibits the highest accuracy with accelerated training times in comparison to other formats. Furthermore, the scalable format necessitates only 25% of the original pixel count for a 96% classification success rate. The utilization of the NxN scalable format for machine code instruction representation results in enhanced accuracy, accelerated training, and a considerable reduction in pixel usage, indicating a promising avenue for optimizing the efficiency of malware detection.

In compressed sensing, a measurement matrix having low coherence with a specified sparse dictionary has been shown to be advantageous over a Gaussian random matrix in terms of reconstruction performance.In this paper the problem of efficiently designing the measurement matrix is addressed.The measurement matrix is designed by iteratively minimizing the difference between the Gram matrix of the sensing matrix and a target Gram matrix.A new target Gram matrix is designed by applying singular value decomposition to the sensing matrix and utilizing entry shrinking in the Gram matrix, leading to lower mutual coherence indicators.An improved Nesterov accelerated gradient algorithm is derived to update the measurement matrix, which can improve the convergence behavior.An efficient optimization algorithm for measurement matrix is proposed on the basis of alternating minimization.The experimental results and analysis show that the proposed algorithm performs well in terms of both computational complexity and reconstruction performance.

Problem statement. Currently, increasingly stringent requirements are being imposed on the tacti-cal and technical characteristics of on-board special complexes from space systems. The existing way of modernizing these complexes, which consists in optimizing individual parameters, does not allow us to provide fundamentally new, and sometimes even optimal, characteristics of the final product. In this regard, it is becoming relevant to create a methodology for designing on-board special complexes using digital twin technology in terms of automating the procedure for building models of complex technical systems, developing methods for representing general mathematical objects of the system, and forming a methodology for computational experiments to obtain information necessary for creating on-board special complexes. Goal. Optimize the model of an on-board special complex using digital twin technology. Result. A method for optimizing the structure of special equipment of an on-board computing complex is presented. An analysis of the implementation of the model with the formation of requirements for the components of on-board special equipment is carried out. The prospects of achieving the maximum values of optimal criteria are assessed. Practical significance. The use of digital twin technology in the creation of on-board special complexes makes it possible to carefully analyze and eliminate possible problems at the early stages of design, simulate their operation on Earth without using significant resources and conducting tests in space.

The task of determining the parameters of objects based on their infrared characteristics is one of the key challenges in the field of electronic warfare. However, traditional methods for solving this problem require a significant computational resource, which limits their application in real-time conditions. Therefore, the development of a universal and efficient method based on the use of neural networks appears to be relevant and in demand. Despite the detailed description of the signal recognition problem in the radio frequency range using neural networks, the issue of a similar problem in the infrared range remains unresolved. In this regard, addressing the task of object recognition based on its signal characteristics in the infrared wavelength range using the neural network described in this work is both relevant and in demand. Experimental studies have shown that the proposed method ensures high accuracy in object recognition. The results confirmed that the radial basis neural network can effectively tackle the task of classifying objects in the infrared range, making this approach promising for practical applications. The use of the proposed method significantly reduces the time and computational costs associated with object recognition tasks. Due to its adaptability to various input data, the method can be successfully applied in optoelectronic surveillance systems, enhancing their efficiency and lowering operational costs.

Statement of the problem. When analyzing the noise immunity of radio engineering systems (RES) for transmitting information with signals with spectrum expansion, it is necessary to consider their operation under conditions of narrow-band interference acting in part of the signal frequency band. The approach under consideration is intended for the analytical calculation of noise immunity indicators under these conditions, based on determining the equivalent signal/noise ratio, taking into account the effect of both broadband and narrow-band interference. Objective. To present an approach to the analytical calculation of the noise immunity indicators of the RTS for transmitting information with signals with spectrum expansion under conditions of narrow-band interference acting in part of the signal frequency band. Results. The relationships for the narrow-band interference parameter and the equivalent signal-to-noise ratio under conditions of combined action of broadband and narrow-band interference are considered. The calculated dependencies of the narrow-band interference parameter, depending on its frequency parameters, and the probability of erroneous reception of a code symbol in the RTS of information transmission with signals with spectrum spreading under conditions of narrow -band noise interference are presented. A significant influence of the frequency parameters of narrow-band interference on the quality of signal reception is shown. Practical significance. Analysis of the noise immunity of RTS with signals with spectrum spreading under conditions of various types of interference is necessary for solving applied problems of designing RTS and means of their electronic suppression.

Currently, there is a contradiction between the need to drastically reduce the time and cost of developing and testing samples of weapons and military equipment and the limited capabilities, great complexity and cost of development tools and field test benches. Solving this problem using existing approaches is difficult. It is necessary to develop virtual testing tools, primarily digital counterparts of weapons and military equipment. Thus, the formation of one's own foundations of the theoretical provisions of the concept of digital twins is relevant. The purpose of the article is to establish the relationship between historical and logical in the concept of "virtual reality" in order to actualize various hypothetical environments and situations that do not really exist and are possible as variants of the development of digital analogues of real-world systems, which will allow controlling a virtual object by modeling the laws of space, time and interaction. The result of the article is the developed implementations of digital twins that improve the quality of operational and technical solutions at the stages of the life cycle of electronic warfare samples. The article implements the concept of synthesis of such categories as a single information space (universal), virtual reality (private), digital twins (singular). The implemented concept and implementations of digital twins can be used in the operational development of new-generation electronic warfare samples. The use of digital twins in the development of weapons and military equipment samples can significantly facilitate the development process, make it faster and less time-consuming and costly, since a digital twin can solve the following tasks without a long, iterative and costly creation of models and experimental samples with subsequent tests on full-scale stands and landfills: evaluation of algorithmic solutions for information processing; testing and debugging of mathematical, software and information support under development; debugging of both internal and external protocols of functional interaction of the developed one, assessment of the bandwidth of data transmission channels; testing support, development of programs and methods of preliminary and state tests. The use of a digital twin makes it possible to simplify the process of creating new-generation radio monitoring equipment that allows detecting and locating radio-electronic weapons controls operating under noise by using incoherent signal accumulation, which makes it possible to effectively counteract radio-electronic weapons controls with any bandwidth of probing signals.

Problem statement. The requirements for the system for determining radio sources involve increasing the effectiveness of radio intelligence in the tactical and operational level of the ground forces by detecting and determining the direction of the enemy's radio source. In this regard, the use of digital twin technology to implement a multi-position direction finder based on an unmanned aerial vehicle to detect enemy radio sources is an urgent task. Goal. To carry out mathematical modeling of a multi-position direction finder in conditions of use in the on-board equipment of an unmanned aerial vehicle and analyze the results obtained. Result. The results of the implementation of the technology of digital twins of a multi-position direction finder are presented. Mathematical modeling of a direction finder operating in the range of 1...7 GHz using the phase method is carried out. The antenna system of the direction finder is calculated, consisting of four antenna elements with a minimum distance of 49 mm between them. It is shown that this distance provides the smallest number of uncertainty hypotheses at the maximum frequency of the operating range and the maximum distance between the antenna elements required for a given accuracy at the minimum frequency of the operating range. It has been established that the combined use of the combined phase and quasi-difference rangefinder method makes it possible to increase the accuracy of determining the location of radio sources. The possibility of using one unmanned aerial vehicle to the developed system has been confirmed to ensure the accuracy requirements for determining radio sources up to 300 m in the frequency ranges L, 5 and C, where the accuracy of the coordinates of radio sources is determined by the quasi-difference rangefinder method, and the phase method is used to eliminate ambiguity. Practical significance. The presented combined phase and quasi-difference rangefinder method can be used in the on-board equipment of an unmanned aerial vehicle.

The technologies of perspective satellite networks suggest their use to form an end-to-end information exchange, regardless of whether the network is terrestrial or non-terrestrial. In this case, the quality of service must be ensured throughout the reception/transmission path. This is directly related to the prospects of using satellite networks in the field of the Internet of Things, for example, to control various unmanned devices. Characteristics of the quality of service such as delay time and the loss probability directly affect the performance of tasks by such unmanned devices. The hybrid satellite networks are also supposed to be used to serve subscribers of 5G/6G networks, but this will require the placement of multi-satellite groupings in low and very low Earth orbits. Thus, promising hybrid satellite networks use a variety of orbits that host a large number of spacecraft (with intersatellite lines), providing heterogeneous communication services, including to subscribers of terrestrial mobile networks. In order to prevent network congestion and maintain the given quality of service in a hybrid network, it is necessary to ensure the functioning of conformed end-to-end quality assurance functions. The main purpose of this work is to provide the basic provisions of the concept of the quality of service in hybrid orbital-terrestrial networks. The main results are the multilevel approach, distributed management, topology-invariant method and wide using software-defined systems. The multi-level approach is based on a multi-agent organization of service quality provision with a hierarchy both by type of orbit and by functional purpose. As a topology-invariant method, it is proposed to use tensor analysis of networks, which provides the possibility of taking into account the process-structural interaction of information flows, the distribution of which across the network affects the quality of service. Software-defined systems allow a flexible approach to the distribution of functions and resources in a multi-agent system by using software-defined networks and software-defined radio. The main results of this work can be used in the formulation of requirements for systems and complexes of perspective hybrid satellite orbital-terrestrial networks. Further, it will be used for multi-agent distributed system of quality of service provision for perspective hybrid satellite-terrestrial networks.