In this paper, we consider the need to assess the influence of the parameters of a linear time-invariant causal system in the processing of quadrature amplitude modulation signals of various positionality and constellation diagram irregularity. We describe the equations that determine the energy balance of a radio line and the total losses arising in route. We have developed mathematical expressions to assess the equivalent energy losses caused by the irregularity of amplitude-frequency and phase-frequency characteristics of the frequency selection filters. We propose a procedure to assess the non-noise losses in the frequency selection filters when designing high-speed radio systems for transmitting the information.

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The purpose of research is to analyze the functionality of classical and advanced sensors for controlling the mechanical parameters of aircraft using the example of strain and vibration sensors to identify their current areas of development.Methods. Research methods are based on the concepts of the theory of sensory systems, the theory of diagnostics and forecasting of the technical condition of aircraft. Methods of multi-criteria analysis, parametric and structural synthesis are used. The principles of operation, as well as the functionality of the main classical sensors used in aircraft to control the parameters of deformation and vibration, are analyzed. A critical assessment of the possibilities of using the analyzed sensors for implementation in various tasks of aviation diagnostics of mechanical parameters has been made.Results. It has been established that the impact of flight loads on the airframe and critical components of aircraft is accompanied by the appearance of hidden deformations in the form of mechanical stresses, which are divided into two components: normal and tangential. Analytical dependencies are obtained for calculating the above quantities using fiber-optic sensors with distributed Bragg cells that convert the change in their own linear dimensions into a change in the reflected wavelength. A necessary condition for obtaining correct measurement results is the temperature compensation of the cells, which makes it possible to localize the places of deformations with an accuracy up to the location of a particular cell. The practical results of using alternative sensors for detecting hidden deformations (cracks) based on radio frequency identification methods in various frequency ranges are presented.Conclusion. The development of the method for diagnosing stress-strain states of aircraft complex units is the use of frequency-Doppler fiber-optic sensors with a high signal-to-noise ratio and a spherical radiation pattern, which will allow developing technical means for monitoring the dynamics of internal deformations of controlled units in real time. As promising areas of research in the field of creating new sensors with new physical properties, fiber-optic Bragg sensors with an inclined grating should be considered.

The purpose of research is to determine the list of necessary controlled parameters of promising aviation systems, which represent a complex system of interaction "pilot - aircraft - environment", as well as to assess the ranges of their change.Methods. Research methods are based on the concepts of the theory of diagnostics and prognosis of the technical condition of aircraft, ergonomic systems. Methods of multi-criteria analysis, parametric and structural synthesis are used.Results. It is shown that the choice of the range of controlled helicopter units is determined by their purpose, the severity of consequences in case of failure, testability, operating conditions and modes, the predicted level of reliability, as well as the experience of operating prototypes and analogues. A variant of organizing a parallel system for diagnosing and predicting the technical condition of advanced aviation systems has been developed. This article presents a stochastic (probabilistic) diagnostic model of damage to the inter-rotor bearing of an aircraft engine, designed to study the correlation dimension of a vibration signal, which imitates the spectral composition of a real vibration signal, with a different form of amplitude distribution density. A decisive rule for predicting engine failure 8-9 flights before the destruction of the inter-rotor bearing is presented.Conclusion. For objective control of the parameters of units of heavy and light helicopters, they are divided into 10 groups, for each of which the composition of diagnostic control sensors is determined based on an analysis of the necessary and sufficient values of the parameters in real time. The range of measurements of specific physical quantities is assigned at the stage of designing one or another vital system of the aircraft. Limits of measurement of parameters are set during regular measurements, as well as at the stages of verification and testing of state control. A variant of the formation of a boundary separating a good and a faulty state, described by a hypersurface, is presented.