Vykhodets A. Improvement of analog- digital system of synchronous broadcast with pilot sidnal

Оbject – processes of operation of the improved system of the stereophonic broadcasting with the difference modulation of signal. An subject – methods of construction of the new hybrid analog-digital system of synchronous stereophonic broadcasting with pilot signal. Methods: mathematical analysis, mathematical statistics, design on computer. Theoretical and practical results: the new improved system of stereophonic broadcasting is offered with the difference modulation in the channel of stereophonic signal; developed and explored new hybrid system of analog-digital sound broadcasting FM/SSB/DRM, in which the digital DRM signal is passed in the upper band of spectrum of pilot-tone system stereophonic signal, and an analog difference signal is passed in a lower band; the new method of measuring of transitional distortions between stereochannels in the network of synchronous FM broadcasting is developed, which allowed in the process of field tests to get information, about the value of protective ratios; theoretical researches allowed to set character and value of transitional and nonlinear distortions at radioreception of signals of the pilot-tone stereophonic broadcasting system and to define information about necessary radio frequency protective ratios; it is set that value of protective ratios, obtained in the process of the conducted measuring in the network of the synchronous FM broadcasting does not have universal character and belong to the concrete areas of territory between synchronous FM transmitters; the new hybrid system of digital sound FM broadcasting is offered, that allows simultaneously pass two stereophonic programs and a few informational or one stereophonic analog and two monophonic digital programs; the parameters of digital channel of the new hybrid system of analog-digital broadcasting FM/SSB/DRM are defined. Results are inculcated at implementation of research work in the Ukrainian research institute of radio and television by agreements with National Radiocompany of Ukraine, Concern of radio, broadcasting and television, and Company ”Interdnestercom” that is confirmed the proper acts of introduction.