Comtech EF Data CDM-625A Installation And Operation Manual page 585

CDM-625A Advanced Satellite Modem
Appendix F
F.5 Operational References
F.5.1 Carrier-in-Carrier Link Budget Calculation
The following steps are required for calculating the link budget for a Carrier-in-Carrier Link:
Step Task
1 Calculate the link budget for both carriers in the duplex link, with required CnC margin:
2
Verify that the PDS ration is within spec for the CDM-625A.
3 Calculate the Allocated Bandwidth (BW) and Power Equivalent Bandwidth (PEB) for the duplex
link:
4 For an optimal link, the Leased Bandwidth and the Power Equivalent Bandwidth should be
equal / nearly equal.
5 Repeat the link budget process by selecting different Modulation and FEC, until the BW and
PEB is nearly balanced.
BW = Greater of (BW
•
Duplex Link
PEB = PEB
•
Duplex Link Carrier 1
Leased BW = Greater of (BW
•
Duplex Link
, BW )
Carrier 1 Carrier 2
+ PEB
Carrier 2
, PEB
Duplex Link
F–17
Revision 0
MN-CDM625A
)
Duplex Link