Radio devices and complexes of strategic application are highly complicated technical systems working under difficult conditions including the conditions of intentional interference. Radio systems have been developed at various times and with various technical parameters and operation requirements, which makes their common use even more difficult due to their mutual influence. The article examines semi-Markov model of maintaining electromagnetic stability of system control for radio complexes. We suggest analytical tools for solving the problem of maintaining electromagnetic compatibility of the total of radio complexes on the basis of the analysis of the state of the model in conditions of interference, the use of state-space representation and the relativity theory. Thus, the suggested tools allow to calculate the efficiency of radio systems operation, probability of task performance for the period not exceeding the predetermined one. The work offers the methods of studying the dependence of this efficiency parameter on the following parameters of system functioning: the expected value of the time of radio system operation during task performance, the expected value of the start of interference, the expected value of restoring RS operation capacity, the probability of the fulfillment of conditions of overlapping frequencies and the interference power exceeding the limit value of the signal power. The resulting mathematical tools allow to calculate the average time of effective radio system functioning in conditions of unintentional and intentional interference, calculate the probability of effective simultaneous work of two radio systems with their unintentional mutual interference. They will also help us determine the optimum plan of frequency resource for interference reduction. We have developed the methods for determining the optimum working plan for a number of heterogeneous radio complexes, thus aiming to build a single effective system of their control by changing dynamically the parameters of their radio emissions.

The object of the study encompasses the control systems for functional elements of complex strategic and specialized systems that serve various purposes and are aimed at achieving set criteria quality and can be interpreted in mathematical terms. The study centres on mathemetical modelling of structural elements of complex multi-level systems and the rationale for determining control actions. The article analyses the complex model of radio electronic communication system. The aim of the study is to solve the problem of multi-parameter adaptation of the system elements to the current conditions at different operating stages by the determination of optimum set of control actions. The study was conducted on the basis of systems theory, system analysis and control, and methods of search optimization. The rationale for determining control actions allows to obtain current and prognostic data on control actions assessment. The technique for determining and establishing rational control actions affecting the system components was developed on the basis of set qualitative states of the system. The main advantage of the developed technique is its multi-purpose application to elements of various complex strategic, social and economic, specialized systems. The technique excludes excessive iteration during calculations, which means economic use of time resources. The technique allows to control effectively the system elements within the limits of criteria set level not only when it is necessary to use additional resources but also when the system resources are used inefficiently and unreasonably.

Radio-electronic means for various purposes are classified as complex systems and are characterized by a multilevel hierarchical structure in the form of separate units, blocks, and modules. As the system is influenced by a complex of factors in the process of operation, reliability of complex systems functioning depends on the reliability of the system elements and optimal distribution of reliability indicators between the elements of the system. The purpose of this article is to define the reliability requirements for structural elements, taking into account failure rates, and possible gradual changes in parameters of the designed system elements. It is required to ensure the minimum cost for a given level of the system reliability. Systems analysis method, reliability of complex systems theory and probability theory are used in the article with reference to failure rates and changing parameters in the process of operation. This approach provides an opportunity to complement the known methods and to obtain analytical expressions for solving design problems of ensuring the reliability with reference to possible gradual and sudden failures, as well as possible gradual changing in parameters of the designed system elements. It is proposed to apply the developed methodology for defining the reliability requirements for the elements of complex technical systems at the early design stages, when the lack of information makes it impossible to find the optimal distribution of reliability norms for structural elements, providing the minimum total cost of the product. In addition, the method for determining the reliability of structural elements can be used to design highly reliable onboard radio-electronic systems of long-term operation.

The description of a way of contactless measurement of the module and a component of a vector of vibro movement of a point is given in a range microwave oven antenna mirror surface by the automatic analysis of geometrical parameters of a trace of vibration degradation of a round tag which center coincides with this point.

The paper proves the necessity of taking into account external conductive layers of the printed circuit board with the thermal physical designing radio-electronic means. For example, a single printed circuit board shows the level of influence of the external conductive layer on the thermal conditions of the printed circuit board. It proved the influence of Joule heat in the thermal conditions of a single conductor. Developed geometrical and thermal printed circuit board models take into account the topological layer and can improve the accuracy of determining the thermal conditions of the printed circuit board.

Increasing density of arrangement of radio-electronic equipment of different purpose, especially on-board equipment, limits significantly the possibility of heat removal by means of ventilation and convection in multi-level radio-electronic modules. At the same time, conductive method of heat removal, that suggests the use of heat mode support systems, special heat-exchange materials for sealing elements of radio-electronic devices. The aim of the research is to analysis possible mathematical models of heat exchange processes in radio-electronic modules in the form of analytical solutions. The article suggests the mathematical model of the analysis and heat mode support in radio-electronic devices and complexes in the form of quasihomogeneous non-isotropic parallelepiped with stationary three-dimensional or flat heat sources, placed in the surrounding conventions environment with stable temperature. This approach gives the opportunity to implement the following procedures: complex spatial arrangement of heat sources exchanged for simpler ones; multi-component subsystems with nonhomogeneous structures exchanged for quasi-homogeneous areas with effective values of heat-transfer properties; spatial arrangement of values describing heat exchange processes at the edges of the areas substituted by their mean values. The suggested approach allows simplifying substantially the expected value of temperature fields and these models can be widely applied for calculation, measurement, and analysis of heat modes in radio-electronic modules with high density of arrangement of radioelectronic equipment.