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Information × Registration Number 0218U003446, 0116U003565 , R & D reports Title Digital television signals transmission metods via radio relay communication lines with frequency modulation popup.stage_title Head Tsukanov Oleg Fedorovych, Кандидат технічних наук Registration Date 15-02-2018 Organization National Technіcal University of Ukraine " Igor Sykorsky Kyiv Polytechnic Institute". popup.description2 The ways of further prospective application of the analogue and digital radio relay communication lines operating in Ukraine using frequency modulation for the national television programs propagation in analog format from the capital to radio transmitting television stations of regional television companies are analyzed. It is shown that the current direction of the further application of such radio relay communication lines is the transmission of DVB-T/T2/C digital television signals over them using double (combined or two-step) modulation methods that will allow the development of digital TV broadcasting networks in Ukraine within the framework of the "National television and radio information space" development plan. A method of COFDM/FM double modulation for DVB-T or DVB-T2 signal transmission and a method of QAM/FM double modulation for DVB-C signal transmission over radio frequency-modulated radio relay links are proposed. The main advantages of combined modulation for use in radio relay communication are considered: resistance to nonlinear distortions in the transmission and reception channels, high noise immunity of the radio link, no need to reissue permission to use the radio frequency resource, no need to upgrade the frontend of the radio relay line, and minimal modernization of the modem equipment of radio relay stations. By usage of CAD AWR Microwave Office (Visual System Simulator library), a radio relay link was simulated that uses the COFDM/FM method to transmit to the DVB-T signal. With the use of the equipment of microwave stations "Complex MG" in laboratory conditions, an testbed of a simple three-line radio relay communication line was constructed which consists of a signal generation subsystem, a matching subsystem with a modulator of a transmitting radio relay station modem, a radio link, a matching subsystem with a demodulator of a receiving radio relay station modem, a terminal equipment. With the help of this testbed, tests were carried out that confirmed the practical possibility of transmitting DVB-C/T/T2 digital television signal by COFDM/FM combined modulation and DVB-C digital television signal by QAM/FM combined modulation on radio relay communication lines. Product Description popup.authors Авдєєнко Гліб Леонідович Цуканов Олег Федорович Якорнов Євгеній Аркадійович popup.nrat_date 2020-04-02 Close