Calculate Max Power; Max Power; Target Ebno; Speed Up Ebno - Comtech EF Data Vipersat CDM-570 User Manual

V i p e r s a t C o n f i g u r a t io n
is recommended; although DPC will function using Viterbi, this type requires
significantly more power to operate and is not recommended.
Enter F at the command prompt to set this parameter.

Calculate Max Power

Once all of the Max Power parameters have been set, enter A at the command
prompt to execute the maximum power calculation for this site.

Max Power

This menu item is information only and displays the result of the last calculation
that was performed for the maximum achievable power level. During network
operations, this level will only be reached when the environmental conditions
are at diminished capacities (e.g., rain fade) and all of the DPC power parame-
ters have reached their maximums.

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 E /N . This information is sent back to the transmitting
b 0
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 3-77. The default value for this parame-
ter is 10 dB.
Figure 3-77
Target EbNo prompt

Speed Up EbNo

Normally, the DPC message is sent every 60 seconds from each terminal in the
network. If the received E /N level at the demodulator drops below the Speed
b 0
Up EbNo set value, the corresponding terminal increases its message 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.
C h ap t e r U s i n g t h e C o m m a n d L in e I n t e r f a c e ( C L I )
3 - 3-59