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Oct 14th, 2009 at 12:59pm
SR = Symbol Rate DR = Data Rate = the information rate. This is the same as the customer information rate if there is no framing, packet header, supervisory, conditional access or encryption overhead added to the data stream in the modem. DVB modems and IP packets add significant overheads. CR = FEC Code Rate. Eg. 5/16, 21/44, 1/2, 2/3, 3/4, 5/6, 7/8, 188/204, 0.95 m = modulation factor (transmission rate bits per symbol). BPSK=1, QPSK=2, 8PSK=3, 8QAM =3, 16QAM=4 etc
Formula: SR = DR / (m x CR)
Best regards, Eric.
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