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The algorithm of obtaining ionograms of oblique sounding of wideband radio channels was implemented in software. The paper presents an algorithm of computer filtering of ionograms with the use of median equalization. The algorithm of determining signal-to-noise ratio in HF ionospheric radio channel was developed and implemented in software.

Modern radio systems that use a transionospheric channel, are required signal bandwidth expansion. However, with a significant bandwidth expansion, there is a problem of dispersive distortions signals due to different phase speed of its spectral components. Evaluation of distortions is required comprehensive research of frequency dispersion for such radio channels. The aim of the research is to solve this problem. Formulated the general provisions of theory of frequency dispersion of phase shift in a medium. Formulas are obtained for components of dispersion through the approximation of a refractive index of a wave at a satellite-to-Earth link. Dependencies were obtained to evaluate dispersion parameters of various orders by the integral characteristics of electron density profile. Expressions were obtained for band coherence of wideband transionospheric channels and method of its evaluation, also we present the algorithm for constructing diagnostic maps of bands coherence for different regions by data of receiving stations of satellite navigation systems.

The development of passive ionosonde that enables to assess the information of technological characteristics of ionospheric radio channel in real time, was carried, which is part of the long distance HF communications systems. On its basis there was conducted applied research of the effect of radio blackout of HF communications caused by the X-ray flare on the sun on the frequency capacity of the multi-dimensional ionospheric radio. It was found out that the blackout of R2 category leads to the cessation of HF communication about 2600 telephone channels, i.e. frequency channel capacity is reduced by 34%. It was set that the relaxation time of blackout is in 1.7 times more than the relaxation time of the X-ray flash.

Scientific substantiation of the adaptive noise whitening algorithm is given in the HF band when receiving a continuous chirp signal. The software implementation of the algorithm is presented. Full-scale experiments were conducted, using the developed device with a continuous chirp signal, based on the technology of software-defined radio systems. It is established that whitening tends to equalize noise level throughout the HF band. Some rare emissions of whitening spectrum do not exceed the range of 10 dB.

We propose an approach to solving the problem of mobile management and the analysis of data of oblique sounding of an ionosphere and ionospheric HF radio channels on a network of radio links. On the basis of our research, we have shown the way to solve this problem, illustrated by diagrams of client-server architectures, mobile client interface and a mobile system to interaction with the receiving terminal.