Konstantin Anatolyevich Vytovtov

The problem of electromagnetic monitoring, detection and tracking of low-power radio emission from unmanned aerial vehicles (UAVs) using the amplitude-difference method is being solved. An overview of the most commonly used signals of telemetry and control of UAVs has been conducted, their spectral electromagnetic portraits have been evaluated, an amplitude-difference method for tracking low-power radiation sources of UAVs has been described, and an automatic air space monitoring system has been developed. Special attention is paid to the multi-lobed nature of the antenna-feeder system's directional patterns, methods for reducing side lobes, and the resulting nonlinear effects. The effectiveness of the proposed method of increasing the sensitivity of the radio locator is analytically shown, the possibility of linearization and increasing the average steepness of the direction-finding characteristics of the antenna system by introducing a decoupling device is demonstrated. The described decoupling device is a flat multilayer dielectric structure with losses capable of effectively absorbing electromagnetic radiation over a wide range of wavelengths and incident angles. A distinctive feature of the proposed monitoring system is its operation in a completely passive mode, i.e. without emitting electromagnetic energy into the surrounding space, which significantly increases electromagnetic compatibility and simplifies the process of implementing the system into existing information and communication networks. The described system is designed to solve the problem of airspace zoning, increase the safety of the civil engineering sector and critical infrastructure facilities. The described problems and methods of their solution can be useful in the construction of similar amplitude-difference angle-measuring locators, as well as low-power radio direction finders and electromagnetic field sensors.

This study presents a mathematical model capable of evaluating non-stationary operating modes of medical information-measurement systems in order to improve their efficiency. Such systems play a critical role in medicine and are used for forecasting and assessing patient conditions in life-threatening situations. The mathematical model introduced in this work is a multichannel queuing system with impatient requests in a transient regime, along with its performance characteristics. This type of model appropriately describes real-time medical information systems not only during normal operation but also under conditions of reboot, failure, or equipment malfunction. To analyze the transient regime of the multichannel queuing system with impatient requests, a system of Kolmogorov differential equations is used, along with a solution based on the probability transition matrix method. The study derives expressions for determining the average number of requests in the buffer, the probability of request servicing, the absolute and relative throughput of the system, and the transient time. The paper presents the results of a transient regime analysis for an M/M/2/4 system with impatient requests, including numerical calculations for various service rates and abandonment rates of impatient requests from the queue.

The work is devoted to the development of a mathematical model for the evaluation of non-stationary performance characteristics of medical information-measuring systems used in medicine to assess the condition of patients in critical health and life situations. The model is a unilinear mass service system with a finite queue, Poisson input flow and impatient requests, adequately describing the functioning of real-time medical systems including under conditions of equipment malfunctions and failures. The paper presents a system of Kolmogorov differential equations describing the mass service system under study, as well as its solution based on the method of probability transformation matrix. Expressions for finding the probabilities of the system states at an arbitrary moment of time are obtained, as well as non-stationary characteristics of the system performance, such as loss probability, throughput, and transient time. The results of numerical calculations are presented for a system with a buffer size equal to two packets at different ratios of the intensity of leaving impatient requests from the queue and service intensity.

The work is devoted to the development of mathematical models and a method for assessing the reliability of all-optical or so-called photonic switches as one of the key elements of a control system built on the basis of modern technical means. The proposed method includes the development of block diagrams of the reliability of switches based on an analysis of their architectures, operating algorithms and control methods. Mathematical models are presented to calculate the reliability function as well as the average system operating time before failure occurs based on various failure distributions, such as exponential and Weibull–Gnedenko distributions. A comparison of reliability functions is presented for various options for constructing all-optical switches, taking into account the manufacturing technologies of basic elements, construction scheme and control method.

A fundamentally new model of an optical switch with decentralized control is proposed. The advantage of the optical switch is the ability to build scalable