Zaichenko V. Method of control and diagnostics in digital combined radio engineering systems.

The object of research is the process of monitoring and diagnosing in digital combined radio system on the path of using a multipath fading simulator. The subject of the research is a model of the system of control and diagnostics of the digital combined radio engineering system. Methods of research. The mathematical apparatus of modified Bessel fractional functions, Jacobi elliptic functions, elliptic integrals, theta-functions in methods of combating intersymbol interference is applied. Elements of probability theory and theory of random processes using analytical expressions of the distribution function and probability densities in the simulation of multipath channels with fading. Bernstein's double series are used, which converge perfectly and evenly in the simulation of the troposcatter canal. The method of decomposition is used in the work, the essence of which is to divide the structure into independently modeled parts. The decomposition method, for example, has been widely used in the internal problems of applied electrodynamics. Theoretical and practical results: the first method of control and diagnostics is proposed, which consists in the construction and scientific substantiation of the model of the control and diagnostics system for combined radio engineering systems of various purpose with the possibility of imitation of the signal propagation medium, which is a multibeam channel with fading between modes. interference and allows to control and diagnose the communication channel in comparison with the known terrestrial radio engineering complexes ez radio without creating physical analogue and conducting field tests; was first proposed to reduce intersymbol interference in multipath channels with fading inputs of the function F(ξ), which describes the shape of a finite-duration signal that differs from the known "raised cosine" type with steeper slopes, and found an analytic view of the function F(ξ) through modified fractional Bessel functions; methods of combating intersymbol interference in multipath channels with fading have been further developed based on a modification of the Kalman digital filter scheme that differs from the known distortion estimation algorithm in such a channel, which is based on a two-parameter probability density distribution; the model of multipath channel applied to the channel with the transmission of information on several frequencies and whose system functions are written through complete elliptic Jacobi functions and elliptic integrals; mathematical modeling of the multipath channel simulator was further developed by describing the signal level distribution function at the multipath channel receiving point with double fading, which absolutely and uniformly converges, which generalizes the known distribution functions of the laws of distribution of fast and slow.