Dpc With Acm - Comtec CDM-840 Installation And Operation Manual

CDM-840 Remote Router
Appendix M
M.2.3.3

DPC with ACM

DPC and ACM function independent of one another, whereby power is modified first or second
in combination with ACM. Depending on conditions, DPC and ACM can be operated exclusively
or in combination, sharing the same resources for checks and balances. When DPC and ACM are
operating in combination, the CDM-840 receives the LQRM comparing value to current settings
and depending on conditions adjusts power or modifies ModCod.
Figure M-5 depicts Dynamic Power Control operating with ACM.
•
As Carrier-to-Noise Ratio (C/N) is decreased, output power is increased until rated maximum
power margin is achieved, clamping power change.
•
As C/N continues to decrease, the ACM function commences to reduce ModCod.
• Further, as C/N increases, ModCod is adjusted, first leaving power at maximum until quality
indicates reduction in power. Such reduction represents the terminal power control
operating without hub backoff information, preventing power from increasing beyond
margin.
Figure M-5. DPC with ACM at Rate Max Power
M–12
MN-CDM840
Revision 3