Target Ebno; Target Range; Speed Up Ebno; Figure 3-57 Target Ebno Prompt - Comtech EF Data Vipersat CDM-570 User Manual

V i p e r s a t C o nf i g u r a t i o n

Target EbNo

The Target EbNo is the desired operating receive level for closed loop servo
control. This is the value used by the receiving CDM-570/570L for comparison
with the actual received Eb/No. This information is sent back to the transmitting
terminal for output power level adjustment as necessary.
Enter T at the command prompt in the DPC Configuration screen to display
the Target EbNo dialog shown in figure 3-57. The default value for this parame-
ter is 10 dB.
Figure 3-57
Target EbNo prompt

Target Range

The Target Range command sets the range on either side of the Target EbNo
value, plus or minus, where the received level at the demodulator is acceptable
and no adjustment to the output power of the transmitting terminal is necessary.
Enter R at the command prompt in the DPC Configuration screen to display
the Target Range dialog shown in figure 3-58. The default value for this param-
eter is 0.2 dB.
Figure 3-58
Target Range prompt

Speed Up EbNo

Normally, the PLDM (Path Loss Data Multicast) is sent every 60 seconds from
each terminal in the network. If the received Eb/No level at the demodulator
drops below the Speed Up EbNo set value, the corresponding terminal
increases its PLDM send rate to every 15 seconds until the receive level is
greater than the set value. This provides a loop speed up to rapidly regain link
quality.
V i p e r s a t C D M - 5 7 0 / 5 7 0 L U s e r G u i d e
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