Radyne ComStream TIERNAN SE4000, Инструкция по установке и эксплуатации

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SE4000 MPEG-2 Contribution Encoder Using a Remote Unit
01-0934-401-B 4-17
SE4000 Remote Command Descriptions
Remote Command Parameter
Range
Factory
Default
Description
MOD CAR_TYPE NORM, CW NORM Norm – Normal modulation
CW – Pure CW carrier
MOD CODE_RATE 1/2, 2/3, 3/4,
5/6, 7/8
5/6 Viterbi code rate; sets the code rate for forward
error correction (FEC) of the modulated signal.
The rate selected indicates the number of error
correction bits that will be added to the data
stream. For example, if you select the 5/6 rate, for
every 5 bits that are input to the FEC encoder, the
FEC encoder outputs 6 bits.
Viterbi forward error correction increases the
transmitted symbol rate by increasing the number
of bits in the data stream.
Front panel command equivalent:
Config>Output>Code Rate
MOD DATA_RATE 1,000,000 to
108,000,000
bps
8448000 Data rate; used to set the modulator input transport
stream data rate.
The data rate you enter is a function of the symbol
rate and the code rate.
The data rate may be entered directly by issuing a
MOD DR command or may be computed based
upon the symbol rate you enter. Specifically, the
data rate is equal to the Symbol Rate x 2 x 188/204
x V, where V = the Viterbi code rate.
Front panel command equivalent: none
MOD SPEC_INV Inverted,
Normal
Normal Spectrum Inversion; used to set the modulator so
that the modulated IF spectrum is inverted.
Parameters are:
? Inverted = the modulated IF spectrum is
inverted.
? Normal = the modulated IF spectrum is not
inverted.
Front panel command equivalent:
Config>Output>Spect Invert