MODULATION AND DEMODULATION METHOD FOR SATELLITE COMMUNICATION USING WIDESPREAD SIGNAL TO NOISE RATIO

摘要

PURPOSE: A modulation and demodulation method for satellite communications having a wide range of SNR is provided to transmit data in satellite communications and broadcasting systems based on DVB-S2 at various SNR levels without any effects on conventional terminals based on DVB-S2. CONSTITUTION: A dummy frame is added to a broadcasting/communication signal frame to transmit signals of a DVB-S2 modulator (301). A spreading factor is identified (302). An identical physical layer header is repeated as many as the corresponding number of the spreading factor, and added to the broadcasting/communication signal frame to which the dummy framed is added (303). [Reference numerals] (301) Dummy frame is added to a broadcasting/communication signal frame; (302) Spreading factor is identified; (303) Identical physical layer header is added by being repeated as many as the corresponding number of the spreading factor; (AA) Start; (BB) End