
March 2015 5
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A1.1.3
Digital SATELLITE Television FIRST Generation
(DVB-S standard/QPSK modulation)
DVB-S Parameters
► Channel Bandwidth
It displays the channel bandwidth from 1.3 MHz to 60.75 MHz.
► Spectral inversion
It detects if the input signal has been inverted.
► Symbol Rate
It represents the number of times that the signal status changes in a
period of time. The bandwidth is related to this parameter.
► Roll-Off Factor
Roll-off factor of Nyquist filter. It indicates the excess of bandwidth over
the ideal bandwidth
► Constellation
QPSK modulation for constellations with DVB-S signals.
► Code rate
Also known as Viterbi ratio. It defines the ratio between the number of
data bits and the total number of bits transmitted (the difference
corresponds to the number of control bits for the error detection and
recovery). This value should be between 1/2, 2/3, 3/4, 5/6 and 7/8.
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