Televes FSM 500, Руководство пользователя

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3.3.3.2.2.4.1.- COFDM (only terrestrial band)
Carry out the BER measurement of the digital terrestria signals with COFDM modulation. The
submenu for this type of modulation is the following:
Figure 74.- COFDM measurements
3.3.3.2.2.4.1.1.- Parameters
When this menu is selected, a window appears on top of the BER measurement window which
displays a list of the parameters that can be selected. To vary a specific parameter, use the
rotating knob (selecting and pressing), a window will appear with a list of all the possible values
for this parameter. The parameters tha can vary in COFDM are: Number of carriers (
2K , 8K ,
AUTO ), Spectrum Inversion ( ON , OFF , AUTO ), Guard Interval ( 1/32 , 1/16 , 1/8 , 1/4 , AUTO ),
Offset ( 0, 1/6 , 2/6 , 3/6 , -1/6 , -2/6 , -3/6 , AUTO ). When the AUTO option is selected in any of
the parameters, the equipment automatically selects the appropriate option, although the
locking time will increase.
Below is an example of a parameter selection window:
Figure 75.- COFDM parameters
Possible parameters that
can be selected using
the rotating knob
Current parameter
values
Information on the type
of modulation
3.3.3.2.2.4.1.1
3.3.3.2.2.4.1.2
3.3.3.2.2.4.1.3
3.3.3.2.2.4.1.4
Multimetter FSM 500 Ref. 5903
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