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This paper discusses the issue of DVB-S2 digital television signal generation from a multi-program transport TV stream using an Nuand BladeRF x40 SDR transceiver operating under the GNURadio software environment. The quality of the generated DVB-S2 signal was evaluated in the process of its demodulation and decoding using the Prof 7500 DVB-S2 satellite TV signals receiver, running under the control of CrazyScan and TSReader programs. Research results showed the possibility of generating a DVB-S2 signal with standard roll-off factors of 0.2 and even with roll-off factors of 0.1 and 0.05, which is equivalent to reducing the frequency band occupied by a DVB-S2 signal with constant symbol rate to 8.3% and 12.5% respectively or transport stream bitrate increase up to 9,1% and 14,3% with constant DVB-S2 signal bandwidth. Also its shown that roll-off values usage less than 0.05 reduces the the DVB-S2 signal bandwidth but leads to the signal-to-noise ratio degradation by 6..10 dB. This paper will be useful for developers of television equipment based on the application of modern standards of digital TV. |
