Power Reference In Dpc Operation; Set Power Reference - Comtec CDM-840 Installation And Operation Manual

CDM-840 Remote Router
Appendix M
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4. Use the drop-down list in the Tx Dynamic Power Control Configuration section of the
CDM-840 HTTP Interface 'Configuration | WAN | Mod | DPC' page to enable DPC. Click
[Submit] when done.
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M.3.1.2

Power Reference in DPC Operation

Once DPC is configured, the power reference setting is vital to the overall operation of DPC. The
reference setting is an automatic feature that requires a dSCPC transmission link between a
CDM-840 and its corresponding CDD-880 at the hub; outbound communication is assumed. The
link can be statically or dynamically established, and at any data rate at or below budget
maximum.
When calibrating the reference, the system uses the ACL to adjust power until it reaches the
optimal target value. This is accomplished through an exchange of messaging between units at a
fast rate – taking the set values, adjusting power, and comparing against limits before allowing
the reference set to complete.
M.3.1.2.1

Set Power Reference

To set the reference, the remote must be operating with an established link in dSCPC. The link
data rate can be anywhere between remote site minimum or maximum, and MODCOD is at
(default) maximum.
It is not important to enable ACM at this time.
Leave the Target Es/No Margin at 0.0.
Dynamic Power Control provides additional power margin for all of the
MODCOD switch points. Adding any ACM margin will deduct from the DPC
power margin, which is a one-for-one subtraction.
When operating in dSCPC, the Max MODCOD is set automatically from the
Site Default MODCOD setting. The Max MODCOD drop-down list is
therefore dimmed, allowing no selection.
ACM is not required for DPC operation.
Terminal Maximum Power is left at "Not Set" at this time and will not be
applied until hub fade detection is available.
M–20
MN-CDM840
Revision 3