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The subject of the manuscript is the algorithms for radar imaging. This research develops imaging methods and algorithms for wideband and ultrawideband active aperture synthesis systems with antenna arrays and stochastic probing signals. The use of antenna arrays makes it possible to obtain radar images without the need to move radar or antenna system in space. The use of wideband and ultra-wideband stochastic probing signals is justified by their narrow autocorrelation functions. This increased the resolution of the obtained images. The main idea of the proposed algorithms is to filter the original wideband signal into several narrowband processes. Furthermore, only the central frequencies of each narrowband signal were processed. This approach allows us to use the classical widespread methods of aperture synthesis for the case of a wideband signal. Usually, they are applicable only for narrowband signals that satisfy the condition of a quasi-monochromatic approximation. This significantly reduces the overall computational complexity of the imaging algorithm, which simplifies its further practical implementation on the existing radioelement base. Because of the simulation, a primary radar image has been obtained and the overall performance of the proposed approach to processing wideband signals has been confirmed. An increase in the quality of the obtained image when using a multiple of frequency ranges is shown. An experimental study of the effect of processing a wideband signal only at its centre frequency instead of the entire frequency band is conducted. During the experiment, the correlation functions of the signals received by two spaced receivers were obtained. As a result, the Van Cittert-Zernike theorem has been experimentally confirmed. It allows signal processing only at its centre frequency instead of the entire frequency band. Simultaneously, the prospect of expanding the bandwidth of the probing signal is indicated. It, in the presence of a wideband element base and devices for high-speed signal processing, will further increase the imaging resolution of a radar system.

The focus of this study is the arrangement of a rational control technique used to maintain the airflow temperature in a vortex energy separator (VES) under destabilizing effects. The objectives include the development of tools for the rational control of temperature in the cold and hot air flows of a VES. Methods used: Discrete state space, production rule statement, resolution of two-valued predicate equations, dichotomous trees, diagnosis, and recovery of dynamic objects. Problems settled: the studied features of the vortex energy separation process, architecture, and operation links of the rational control system were considered, mathematical models were deduced, and tools for diagnosing and recovering the efficiency of the vortex energy separator as a rational control object were developed. The scientific novelty of the study lies in the formation of instrumental tools to provide rational control of the airflow condition in the VES, where the control object is subjected to the substantial influence of various destabilizing effects.

The object of study in this article is the formation process of a rational control of the temperature of a vortex energy separator under destabilizing influences. The subject matter of the article is the process of forming a dichotomous tree by two-digit predicates from diagnostic models a vortex energy-separator device as a rational control object when destabilizing influences appear, and its further recovery. The goal is to develop an analytical approach to the formation of digital algorithms for the rational control of cold and hot air flow temperatures of a vortex energy separator. The tasks are to study the features of the process in the vortex energy-separator device; to describe a rational control system of the vortex energy-separator device; to analyze the experimental characteristics of the vortex energy-separator device; to form linear mathematical models of the nominal mode of the vortex energy-separator device; to develop linear diagnostic models that describe the inoperable states of the vortex energy separator as a rational control object; to form logical signs of diagnosing using diagnostic models, to develop recovering algorithms for the vortex energy separator. The methods used are transfer functions, discrete state space, forming production rules, two-digit predicate equations, dichotomous trees, diagnosing and recovering the operability of dynamic objects. The following results were obtained: the vortex energy-separation process features analysis, the rational control system structure and function description, the experimental characteristics analysis, the development of mathematical models, diagnostic and recovering tool development for the emergency operation process of a vortex energy separator as a rational control object for a given destabilizing influence set. Conclusions. Scientific novelty is the development of an analytical approach to the development of rational control of the vortex separation process of the air flow under the significant influence of various kinds of destabilizing influences.

The object of study in the article is the vortex effect of temperature separation in a rotating gas flow, which is realized in small-sized vortex energy separators. The subject matter of this article is the process of forming diagnostic models of inoperable states of a vortex energy separator device as a rational control object when destabilizing influences appear. The goal is to develop an analytical approach to the formation of digital diagnostic models for rational control of cold and hot air flow temperatures that reflect the effects of direct signs of inoperable states of the vortex energy separator device that are inaccessible to measurement with indirect signs accessible to measurement. The tasks are to study the features of the process in the vortex energy separator device; to describe a rational control system of the vortex energy separator device; to analyze the experimental characteristics of the vortex energy separator device; to form linear mathematical models of the nominal mode of the vortex energy separator device; to develop linear diagnostic models that describe the inoperable states of the vortex energy separator as a rational control object; to form logical signs of diagnosing using diagnostic models. The methods used are the method of transfer functions, the method of the discrete states space, the method of diagnostic models, the method for forming production rules, the method of formation of two-digit predicate equations. The following results were obtained: linear mathematical models of functional elements and the entire device as a whole were formed for the nominal operation mode. Linear digital diagnostic models were developed for the inoperable states of the vortex energy separator device. Logical signs of diagnosis were formed on the basis of the diagnostic models. Conclusions. The scientific novelty lies in the formation of an analytical approach to the development of digital diagnostic models of inoperable states of the vortex energy separator device and two-digit predicate equations of indirect signs for a dichotomous diagnostic tree.

Within the maximum likelihood method an optimal algorithm for polarization target selection against the background of interfering signal reflected from the earth’s surface is synthesized. The algorithm contains joint operations of spectral interference rejection and their polarization compensation by means of certain combinations of interchannel subtraction of signals of different polarizations. The physical features of the elements of the polarization scattering matrix are investigated for the technical implementation of the synthesized algorithm.

Using the statistical theory of optimization of radio engineering systems the optimal method of coherent radar imaging of surfaces in airborne synthetic aperture radar with planar antenna arrays is developed. This method summarizes several modes of terrain observation and it is fully consistent with current trends in the development of cognitive radars with the possibilities of radiation pattern restructuring in space and adaptive reception of reflected signals. Possible modifications of the obtained optimal method for the operation of high-precision airborne radars with a wide swath are presented. The idea is to create a theoretical basis and lay the foundations for its practical application in solving a wide range of issues of statistical optimization of methods and algorithms for optimal spatiotemporal signal processing in cognitive radar systems for the formation of both high-precision and global radar images. To implement the idea, the article highlights the concept of statistical optimization of spatio-temporal processing of electromagnetic fields in on-board cognitive radar systems, which will be based on the synthesis and analysis of methods, algorithms and structures of radar devices for coherent imaging, the study of limiting errors in restoring the spatial distribution of the complex scattering coefficient, the synthesis of optimal feedback for receiver and transmitter adaptations in accordance with a priori information about the parameters of the objects of study, the area of observation and the existing sources of interference. Objective is to develop the theory and fundamentals of the technical implementation of airborne radar systems for the formation of high-precision radar images in an extended field of view from aerospace carriers. Tasks. To reach the objective it is necessary to solve following tasks: – formalize mathematical models of spatiotemporal stochastic radio signals and develop likelihood functional for observation equations in which the useful signal, receiver internal noise and interference radiation of anthropogenic objects are random processes; – to synthesize algorithms for optimal processing of spatio-temporal stochastic signals in multi-channel radar systems located on aerospace-based mobile platforms; - in accordance with the synthesized methods, to substantiate the block diagrams of their implementation; – obtain analytical expressions for the potential characteristics of the quality of radar imaging and determine the class of probing signals and space scanning methods necessary to perform various tasks of radar surveillance; ‒ to confirm some of the theoretical results by simulation methods, in which to reveal the features of the technical implementation of aerospace remote sensing radar systems.

The production of parts and (or) finished products in electronics, mechanical engineering and other industries is inextricably linked with the control of the accuracy and cleanliness of the processed surfaces. Currently existing meters of parameters of statistically uneven surfaces, both contact and non-contact have some disadvantages, as well as limitations due to methods and design features of measurement. Speckle interferometric methods for measuring parameters of statistically uneven surfaces make it possible to get away from some disadvantages inherent in existing methods and measurements. The use of methods of statistical radio engineering, methods of optimization of statistical solutions and estimates of parameters of predictive distributions for optimal radio engineering system synthesis is promising for the analysis and processing optical-electronic coherent laser space-time signals (speckle images) form with the laser radiation scattered by statistically uneven surfaces. This work synthesizes the optimal algorithm and structure for analyzing the parameters of statistically-temporal surfaces based on spatio-temporal processing of optical speckle interference signals and images using modern methods of optimal synthesis of radio engineering and coherent optoelectronic systems. In this work, an algorithm for processing optical signals scattered by statistically uneven surfaces is synthesized and investigated for problems of optimal estimation of parameters and statistical characteristics of statistically uneven surfaces. A block diagram of the optical contactless device for evaluating the parameters of statistically uneven surfaces is proposed. The limiting errors of estimation parameters of statistically uneven surfaces and the optimal installation angles of the emitters and the optical receiver are investigated. Equations are obtained for estimating the root-mean-square height of the ridges and the correlation radius of small-scale statistically uneven surfaces in the approximation of small perturbations. The proposed method for evaluating the parameters of statistically uneven surfaces allows to increase the accuracy of measurements, to conduct a non-contact assessment of the parameters - even statistically uneven surfaces that have geometric surface irregularities or located in hard-to-reach places, for example, grooves, holes, as well as products of cylindrical, spherical and other shapes.

Subject of study. The article proposes new methods of input and preliminary processing of video data for web- and specialized pi-cameras in monocular and stereo vision systems based on Raspberry Pi microcomputers to improve the quality of work of modern mobile vision systems. This approach is always relevant, since the design of modern vision systems constantly requires new non-trivial hardware, algorithmic and software solutions. Objectives. The goals are to compare quality indicators of the known methods of input and preliminary processing of video data in vision systems and to develop new methods and algorithms providing better speed, the necessary frame resolution and the independence of the frame brightness from changes in scene illumination while reading video data. Methods used. The paper formulates a comprehensive criterion for improving the quality of the Raspberry Pi microcomputer video input and preprocessing video data. Based on the accepted quality indicators (video input speed, resolution, and stability indicators of average brightness of the current frames of the received video stream), video input and preprocessing algorithms that satisfy the specified requirements are synthesized. This allows to find the optimal method for processing video data and to overcome the contradiction of reducing the input speed due to the need of increasing the resolution of video frames for each project. The created universal program for input and preliminary processing of these data allowed to obtain quantitative estimates of the effectiveness of the developed algorithms and formulate recommendations for their further use. All this allows you to significantly increase the efficiency of using Raspberry Pi microcomputers in modern mobile vision systems. The results obtained are the basis for the creation of a universal software product for high-speed input (in real time) and preliminary processing of video data for face detection and recognition systems, as well as stereo vision systems. Conclusions. The conducted experimental studies confirmed the efficiency and effectiveness of the proposed methods and algorithms for high-speed input of video data with different values of the resolution of the frame and the ability to adaptively adjust its brightness. Based on the created methods and algorithms, various options for its software implementation are proposed. This allows us to recommend the results for practical use. Prospects for further research include the expansion of the vector of criteria for assessing quality and features for optimizing video data, as well as the creation of new algorithms and various versions of programs based on them.

Subject of study. The article proposes new method and tool for color correction of web-cameras in stereo vision systems in order to improve the quality of their work. The goal is a comparative analysis of the quality indicators of well-known color correction methods and the development of a new method and working algorithms for the joint procedure for color correction and rectification of video frames of the left and right cameras. Objectives: the task was to carry out a theoretical analysis of the quality indicators of well-known color correction algorithms and methods, to develop new working algorithms, write the program codes of these algorithms in Python using the necessary OpenCV functions. Conduct experimental studies of these algo-rithms. Evaluate the performance of the stereo system in the laboratory, and test the reliability of the results obtained using sta-tistical analysis methods. Methods used: comparative analysis of known methods and algorithms by statistical modeling, syn-thesis of new algorithms and evaluation of the effectiveness of their work by conducting laboratory field tests. The results obtained: a comparative analysis of the performance of the known methods of color correction of stereo cameras was carried out, new efficient algorithm was proposed for solving this problem. Findings. Scientific novelty of the results: new algorithm for correcting the color balance of webcams used in stereoscopic vision systems have been created, featuring high color correction accuracy and working in real time using the functions of the OpenCV library in the Python software environment.

Subject of research is the detection and recognition of faces. The purpose of this work is creation of modified algorithms of face detection, which are providing automatic brightness stabilization of the analyzed image regardless of brightness level. A technique is proposed for assessing the effectiveness of their work in comparison with the classical algorithm. Research methods. We will dwell in more detail on the first part of the problem − face detection and recognition. In the meantime, the most popular method used for searching the face area on an image is the Viola-Jones method, which is popular because of its known high speed and efficiency. It is based on an integral image representation, on the method of constructing classifiers based on adaptive boosting algorithm (AdaBoost) and on the combination classifiers in cascade structure method. The Viola-Jones method is firstly using cascades of wavelets (primitives) - Haar features. All of the above made it possible to build a face detector that works in real-time with a fairly high quality. However, there are a lot of disturbing factors, which are limiting the efficiency of such algorithm work. The major of them are spacial face position ambiguity on the analised image and poor quality of stage lighting. The results of the study. The adaptive algorithms of face detection and recognition on digital images and video sequences in real-time, based on the Viola-Jones method, are suggested. An automatic stabilization of frame brightness is additionally added to the classical structure of such algorithms to compensate an effect of changes in the stage illumination level on quality of face detection. The structure of the algorithms is described and the software developed in Python programming language for a face detection and recognition using OpenCV library resources. Video data is processed in real time. An original method for the efficient estimating of the algorithm based on the criterion of the maximum probability of faces and their main elements (eye, nose, mouth) correct detection is proposed and implemented programmatically. The results of work of classic and suggested algorithms are compared. The examples of work and testing of software are given. Conclusion. The use of the obtained results allows to improve the quality of work and the reliability of the results when recognizing faces in different systems.

Proposed model of technical vision system use for supplementation and clarifying information about surround objects classes and distances, received by driver.

The paper presents a methodology for diagnostic of the technical condition of vehicle. The high accuracy of the actual trajectory of the transport aggregate (TA) is provided by the use of local differential mode of global navigation satellite system (GNSS). Comparing the real and rational trajectories will determine the kinematic and dynamic characteristics of the car.

This article focuses on the development of architecture and technicalsolutions for implementation intelligent transport systems (ITS). The presented system will perform the following functions: monitoring the movement of an object collecting and displaying information about the state of the road, warning of the approaching object to obstacles, routing, as well as control of movement and speed of the output parameters of the recommendations of the movement, the development of intelligent decisions about the choice of optimal routes, intellectual analysis of data (IAD) of the style and movement of the driver (the influence of alcohol), IAD on the technical parameters of the vehicle. Thus, it is advisable for ITS to be divided into several subsystems, which are related but are responsible for one or more functional tasks. Consequently, the need for monitoring the movement subsystem, the database on the state of the object database onthe location of an object, display subsystem, the subsystem of control of the road, the engine safety (prevention of obstacles), the subsystem control parameters of movement, routing subsystem.

Description of the modeling system of differential GNSS mode for the operation ITS is considered. Differential method of navigation allows to precise determination of the coordinates and is not very complicated for technical realization. The coordinates of the consumer are calculated with high accuracy because the base station and the user are located in a short distance from each other. Determination of the origin location is on the same satellite and method of local correction is implemented.