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5.13.3 DVB-T2 (COFDM) Digital Channel Configuration
Press the Measurements Configuration
CONFIGURATION menu and turn the rotary selector
signals parameters which can be defined by user and are described below:
1)
Channel BW (channel bandwidth)
Enables the channel bandwidth to be selected between 5, 6 , 7 and 8 MHz. The
selection of this parameter is essential for the correct operation of the tuner, as it
affects the frequency separation of the carriers.
2)
Spectral Inv. (spectral inversion)
This option enables spectral inversion to be applied to the input signal, though in
the majority of cases it should be in the OFF position (not inversion).
This configuration menu shows, besides the user definable COFDM signal
parameters, the value of the rest of signal parameters detected automatically:
Carriers
Guard Interval
Pilot Pattern
PLP Mode
PLP Code Rate
PLP Constellation COFDM Modulation with QPSK, 16QAM, 64QAM, 256QAM
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It defines the number of modulation carriers between 1k, 2k, 4k, 8k,
8k+EXT, 16k, 16k+EXT, 32k, 32k+EXT.
The Guard Interval parameter corresponds to the dead time
between symbols, its purpose is to permit a correct detection in
multi-path situations. This parameter is defined according to the
symbol length: 1/4, 19/256, 1/8, 19/128, 1/16, 1/32, 1/128.
Several pilot patterns are available, named PP1 to PP8, with the
intention of providing efficient options for different channel scenarios.
Each pattern can (in principle) support time and frequency variations
up to corresponding Nyquist limits. The applicable limits do depend
on certain assumptions as to how the receiver works, in particular
whether it uses interpolation in both time and frequency, or in
frequency only, etc.
It is determined by the number of stream at input. For a single
stream is Single. For several streams is Multiple.
Defines the ratio between the data bits number and the total number
of bits transmitted (the difference corresponds to the number of
control bits for the error detection and recovery): 1/2, 3/5, 2/3, 3/4,
4/5, 5/6
constellations. A constellations refers to all the data from the
selected PLP.
USER'S MANUAL. TV EXPLORER HD +
[17] key to access to the
[1] to access the COFDM
12/2011
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