Promax HD RANGER, User Manual

Page: 81 / 92

A1.1.4
Digital Satellite Television First Generation
(DVB-S / QPSK modulation)
A1.1.4.1 DVB-S Parameters
►
Channel Bandwidth
It displays the channel bandwidth from 1.3 MHz to 60.75 MHz. This
parameter affects the frequency separation of the carriers.
►
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
COFDM Modulation with QPSK constellations.
►
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.
August 2012
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