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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.

Studied the possibility of creating on USRP platform receiving terminal Ionosonde continuous chirp signal and to obtain compared results with the data of ionospheric sounding analog chirped probe. Created on USRP platform receiving terminal chirp ionosonde showed a higher noise immunity, lack of congestion own signal, the possibility of simultaneous studies of the characteristics of direct and global propagation. Developed an algorithm providing frequency HF communication systems based on panoramic radio sensing using a device sold by technology SDR. As a result of experiments conducted on the radio a length of about 3000 km is established that the application of the developed approaches in the trunk radio enhances the probability of error-free reception of test messages from 54% to 84% of cases in the daytime and from 46% to 90% at night. The first values correspond to the case selection OWC by long-term prognosis. Selecting the OWC as a result of sensing link can significantly reduce the power of the connected signal. In the experiments quite often there have been cases where the choice of OWC using the SDR Ionosonde communication system operating signal power 5W had reliability of communication at the level of 97%. The experimental results showed that during tests of various radio technical systems HF band monitoring of ionospheric radio links using chirp probes allows about 10 times to reduce their terms, as well as improve the reliability and informative test results. Thus, this Ionosonde is a modern tool for providing frequency HF communication systems probed the link.