Promax HD RANGER, Руководство пользователя

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A1.1.3
Digital Terrestrial Television Second Generation
(DVB-T2 standard / COFDM modulation)
A1.1.3.1 DVB-T2 Parameters
►
Channel Bandwidth
This parameter affects the frequency separation of the carriers. Its value is
6 MHz, 7 MHz or 8 MHz.
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Spectral inversion
It detects if the input signal has been inverted.
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FFT Mode
It defines the number of modulation carriers between values 1k, 2k, 4k, 8k,
8k + EXT, 16k, 16k + EXT, 32k, 32k + EXT.
►
Pilot Pattern
There are several pilot patterns available from PP1 to PP8, which offer
different features depending on the type of channel. Each pattern supports
time and frequency variations up to the Nyquist limit. Limits depend on
certain characteristics such as the receiver operation, if the interpolation is in
frequency and time or just in time, and so on.
►
Guard Interval
This parameter is the dead time between symbols; its purpose is to detect
problems due to multipath echoes. This parameter is expressed in terms of
the symbol duration: 1/4, 19/256, 1/8, 19/128, 1/16, 1/32, 1/128.
►
Constellation
COFDM modulation with constellations QPSK, 16QAM, 64QAM, 256QAM.
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Constellation rotation
It detects if the constellation is rotated (ON) or not (OFF).
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Code rate
Also known as Viterbi ratio. 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 detection and recovery of errors).
►
PLP id
It is the PLP identifier. In the case of PLP Single mode identifies the input
stream (0-255).In the case of PLP Multiple mode clients can choose the PLP
ID to view.
August 2012
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