An algorithm for accurate estimation of the carrier frequency, which is optimal by the criterion of the min-imum mean square error, is developed which is implemented using relatively short sync combinations distributed over the duration of the packet. The results of the dependence of the accuracy of estimating the carrier frequency on the level of channel noise are presented. Analytical expressions are obtained for an accurate estimate of the frequency and phase errors obtained on the basis of sufficiently short sync combinations. The results of simulation are demon-strated. The research results can be used in satellite radio links with packet data transmission.

The problem of modeling signals of various spatial coherence in radio engineering systems is considered. First, a mathematical model for spatially coherent signals in the form of stochastic differential equations is constructed, followed by its study in the Simulink environment. The following is a method for constructing a mathematical model for a more general case – partially coherent signals, and its accuracy is also evaluated. Based on the developed models, an algorithm for estimating the parameters of partially coherent signals is synthesized. Based on the obtained dependence of the sensitivity of the model to deviation from a priori data, conclusions are drawn about a sufficiently high accuracy of estimation using synthesized algorithms.

The article proposes an algorithm for controlling the electromagnetic environment in a Wi-Fi WLAN using fuzzy logic methods. A power management system for access points has been developed, deployed using the Wi-Fi segment based on existing equipment. The use of an electromagnetic compatibility control system in high-density Wi-Fi networks can significantly improve the bandwidth of the wireless segment.

In work systems analysis of process of target functioning of the satellite command relay system (SCRS) in the conditions of a difficult radio-electronic situation is carried out. The carried-out analysis of perspectives of development of a subsystem of relaying of SKRS of orbital grouping of spacecrafts of remote sensing of Earth, allowed to draw a conclusion on features of a stage of coordination planning of the means of a subsystem of relaying consisting in distribution of SKRS the orbital channel resource (OCR) on the basis of the non-Markov priority systems of service. The model of operational distribution of ROC of a subsystem of relaying on the basis of the priority systems of service in which, unlike the known models, time of stay of the request in a system is limited is received, limits for a type of distribution of holding time of requests are lifted and also expression for calculation of the initial moments of distribution of waiting time of messages of different priorities is received. Use of model allows to evaluate the probability of untimely delivery of details and also to provide required figures of merit of service of priority flows and at the expense of it to provide the required connectivity and stability of SKRS in general.

The paper considers the method of solving the problem of excitation a circular infinite impedance cylinder by means of extrinsic current with an arbitrary spatial orientation. The formal solution of the problem is based on the method of expanding the fields in a complete system of eigenfunctions. Arbitrary distribution of extrinsic currents is taken into account factors excitation. An approximate solution of the problem in the far field is presented. The effect of a dielectric cylinder on the directional diagram of an axial electric dipole is studied.

In this work we seek to approach the choice of the Republic of Angola for the ISDB-T telebroadcasting system. The experimental results of the ISDB-T digital transmission system in the Republic of Angola are Execelente. Currently, the Japanese terrestrial digital broadcasting system (ISDB-T) is used in 14 countries around the world (Argentina, Bolivia, Brazil, Chile, Costa Rica, Japan, Peru, Paraguay, El Salvador, Uruguay, Honduras, Venezuela, Philippines, Botswana) and 6 more countries (Angola, Maldives, Sri Lanka, Guatemala, Ecuador, Nicaragua) have adopted this system. The study shows that ISDB-T is a system applicable in our country, as even with the transmitter operating at 50% of its maximum power, the signal is received in a large part of the city of Luanda, with failures only in regions far from the center urban. The implementation of a fully digital transmitter that is foreseen, the increase of the transmitter's power, among other changes, may provide better advantages in implementing the ISDBT in the Republic of Angola. The commitment comes at a time when Angola plans to cover the entire national territory, starting in 2023.

With the introduction of 187-FL "On the security of critical information infrastructure in the Russian Federation", a class of tasks requiring new approaches was determined. This is due to the solution of not only practical problems with the introduction of this law, but also with the development of its scientific and methodological support, which is one of the tasks of regulators. The main regulatory problem in ensuring the security of critical information infrastructure (CII), in our opinion, is associated with the lack of a systematic approach as a methodological basis for developing requirements for the development of CII. This leads to gross errors and errors in the course of making managerial decisions, therefore, to an increase in information security risks. When considering the subject of CII as a system, there is a need to consider inter-object relationships as sources of destructive influences that can lead to the effect of infrastructural "destructivism", i.e. to the self-destruction of infrastructure. To study this issue at the initial stage, it is proposed to build a model of the states of CII subjects in a static mode. In the course of working with this model, it is possible to predict the development of the situation of self-destruction of the infrastructure of the CII subject in a situation of uncertainty.

Monitoring events and predicting the behavior of a dynamic information system are becoming increasingly important due to the globalization of cloud services and a sharp increase in the volume of processed data. Well-known monitoring systems are used for the timely detection and prompt correction of the anomaly, which require new, more effective and proactive forecasting tools. At the CMG-2013 conference, a method for predicting memory leaks in Java applications was presented, which allows IT teams to automatically release resources by safely restarting services when a certain critical threshold value is reached. Article’s solution implements a simple linear mathematical model for describing the historical trend function. However, in practice, the degradation of memory and other computational resources may not occur gradually, but very quickly, depending on the workload, and therefore, solving the forecasting problem using linear methods is not effective enough.

A method of authentication of keys generated by the Diffie-Hellman method is investigated in the context of the use of a man-in-the-middle attack by an attacker. It is assumed that the users Alice and Bob, who form the key, have pre-distributed random bit strings a and b, respectively, obtained either from some source or generated by themselves based on data obtained from magnetometers or accelerometers from mobile devices. The attacker has no access to these chains. A method for authenticating Diffie ‒ Hellman values (DH values) is proposed. For this purpose, the message (DH-value) is divided by Alice into N blocks. For each block, an authenticator is calculated using the Wegman ‒ Carter algorithm with a one-time pad keys, which are sequences a and b. The DH-value and authenticators are transmitted over the channel to Bob, who calculates authenticators from the received DH-value and compares them with the authenticators received from the channel. If the number of unauthenticated blocks does not exceed the set threshold, then DH-value authentication is considered successful. But the drawback of this method is a little disagreement between authenticating strings of different users. The formulas for probabilities of the undetected deception and the false alarm (due to the mismatch of chains a and b) are proved. The optimization of the method parameters (the number of blocks and the length of the authenticator) is carried out, at which the consumption of the authentication key (chains a and b) is minimized when the specified requirements for the probability of the undetected deception and the false alarm are met. Examples of the choice of authentication parameters for a 256-bit DH-value are given.

The problem of finding the optimal solution in a self-organizing autonomous group robotic system under conditions of uncertainty is considered. A method for assessing the quality of group management based on a statistical and probabilistic decision-making criterion under uncertainty conditions has been developed. A distinctive feature of the method is the use of trust metrics. This approach allows us to identify and reduce the influence of destabilizing factors in the process of information interaction in an autonomous group of cyber-physical objects. The results can be used in the development of algorithms for group control of swarms of autonomous robotic complexes.

The article presents the results of measurements of the parameters of the digital radio broadcasting DRM signal quality in the experimental zone of St. Petersburg in order to determine the influence of the transmission modes laid down in the DRM standard on the size of the service area.