Radyne ComStream TIERNAN SE4000, Installation And Operation Manual

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Using a Remote Unit SE4000 MPEG-2 Contribution Encoder
4-22 01-0934-401-B
Front Panel Menu Summary
Command Function Options/Response Format
Config>Output Used to configure and monitor the SE4000 internal modulator and the ASI transport
stream output. When the initial SE4000 installation and configuration is begun, the
modulator output (Mod State) should be turned off until ready to begin satellite
transmissions.
Data Rate Auto
Calc
Controls video bit rate calculation
algorithm
? Auto – Video bit rate is automatically set to the
maximum rate available (default)
? Manual – Video bit rate is manually set under the
video menu.
Modulator
Enable
Setting enables or disables the
internal modulator.
? On - modulator is enabled (default)
? Off - modulator is disabled.
Modulator
Enable Status
Displays the present enable
status
Note: The modulator may be set
Enabled, but automatically
disabled due to a fault condition
or a rate mismatch.
? On - modulator is enabled (default)
? Off - modulator is disabled.
Modulation Type Sets the modulation scheme. ? QPSK (default)
? 8PSK (optional)
? 16QAM (optional)
Carrier Type Sets the modulation poutput into
pure carrier mode
? Norm (default)
? CW – Pure carrier mode
Sets the data rate for the output
transport stream or the
modulator data rate.
? If modulator is disabled: 1 to 80 Mbps default:
8.448 Mbps.
? If modulator is enabled: 1 to 80 Mbps (to 30 Msps).
Data Rate
Additional Information: The data rate that is entered using this parameter determines the
transport output of the SE4000 when the modulator is enabled.
Sets the code rate for forward
error correction (FEC) of the
modulated signal.
1/2, 2/3, 3/4, 5/6, 7/8
default: 5/6
Code Rate
Additional Information: The rate selected indicates the number of error correcting 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.
The relationship between the selected code rate and the data stream prior to modulation,
and an indication of the degree of error correction provided by each code rate is shown
below.
Viterbi Code Rate Transport Stream Data Rate Error Correction
1/2Increases by a factor of 2 (100% increase)Maximum
2/3Increases by a factor of 1.5 (50% increase)Very High
3/4Increases by a factor of 1.33 (33% increase)High
5/6Increases by a factor of 1.2 (20% increase)Moderate
7/8Increases by a factor of 1.14 (14% increase)Low
Sets the current transmission
symbol rate
SymRate
sets the current transmission symbol rate
1.0 to 20.0 Msps
default: 5.500187 Msps Sym Rate
Additional Information: The symbol rate is the number of symbols required to transmit the
data stream over a satellite link using quadrature phase shift keying (QPSK).
The symbol rate is automatically calculated based on the modulator input transport stream
data rate, the Viterbi code rate, and other fixed parameters that add overhead to the data
stream.
If the displayed symbol rate exceeds the allowable satellite bandwidth, the data will be
corrupted during transmission.