Comtech EF Data CDM-570A Installation And Operation Manual page 220

Carrier-in-Carrier (CnC)
Appendix G. D
When CDM-570 Compatibility Mode is selected using the 'Configuration |
Utilities' page (Sect. 7.4.3.3.8), CnC is UNAVAILABLE and this page section
becomes nonfunctional.
•
Mode – Use the drop-down list to set your desired CnC operating mode (Off,
Normal, or CnC-APC variants).
•
Search Delay Range – Enter minimum and maximum values, in ms.
To reduce the time taken for the CnC algorithm to converge, you may apply restrictions to the
range of delay used by the search. During initial link testing, you should set the delay to a
minimum of 240 ms and a maximum of 300 ms. Once CnC has found the exact delay, the
value can be further reduced but care should be taken to allow sufficient range to
accommodate changes in path delay due to Doppler.
If bench-testing CnC with two units in a back-to-back configuration, you
should set the minimum delay to 0 ms, and the maximum delay to 20 ms.
This takes into account the lack of satellite delay.
•
Freq Offset Range – This range is pre-calculated. The Rx symbol rate determines
the CnC Frequency Offset:
o
o
Click [Submit] to save.
Ethernet-based Remote Product Management
CDM-570A/570AL Satellite Modem with Optional Packet Processor
T C
OUBLE ALK ARRIER
From 16 to 64 ksymbols/sec (ksps): ±1 to the symbol rate (ksps/2)
64 ksps and above: ±1 to 32kHz
- -C (CnC) OPTION
IN ARRIER
7–32
Revision 5
MN-CDM570A