No abstract

The article describes and analyzes mathematical models of multiplicative and additive non-Gaussian noises affecting the useful signals. For synthesis and analysis, and, hence, the effective design of information systems and radio devices operating in conditions of intense perturbations it is necessary to choose not only the adequate mathematical model of the useful signals and information processes, but also the corresponding models of random effects, possessing in general non-Gaussian multiplicative and additive character. To describe the arbitrary non-Gaussian noises, which are quasiharmonic processes whose spectrum is close (or narrowband) to the band of the desired signal, the authors used a two-dimensional elliptic symmetric probability density function, including two extreme cases: Gaussian processes and a sinusoidal signal with random initial phase distributed uniformly in the interval [0, 2 π]. Model of correlated non-Gaussian narrowband noises of elliptically symmetric two-dimensional probability density function allows you to make a synthesis of information systems and devices based only on a priori knowledge of one-dimensional probability density function and the correlation function. Because knowing one-dimensional probability density function of the instantaneous values, we can determine the probability density function of the envelope; this makes it possible to use the elliptically symmetric probability density function to describe not only additive, but multiplicative (baseband) noises. To describe the real density of probability density function of the non-Gaussian process, the authors propose to approximate its a priori known one-dimensional probability density function and a specially designed transitional probability density function, and show the adequacy of this approximation of the real two-dimensional probability density function of correlated noises.

Various metrics of evaluation of the quality of the transmitted video information are considered. Algorithms for calculating the objective and subjective ratings of the video information are described, including RMSE, PSNR, PQR, VQM. The main problems are given that appeared in the process of quality assessment and related to the desyncronization of the images and other negative effects associated with the transmission of the video information over the wireless communication channels. In conclusion, a brief comparison of the considered metrics is performed.

Reviewed and analyzed issues associated with the analysis of patterns of density probability distribution of the envelope of the signal reflected from the extended objects that are used in the analysis and synthesis of radio engineering devices of short-range radiolocation.