Comtech EF Data MCED-100 - Manual (Page 88)

MCED-100 MetaCarrier Embedding Device Revision 1
Appendix A MN-MCED100
A–2
A.2 Scenario 1: Marginal Interference
Item Description
A “Interfering” 256 ksps Data Carrier
B “Desired” 3.5 Msps Data Carrier
Figure A-1. Scenario 1 (Marginal Interference)
Figure A‐1 shows a marginal interference scenario where a 256 ksps Data Carrier is interfering
with a 3.5 Msps Data Carrier.
In this situation, the energy of the interfering carrier is not significant. As shown, the 256 ksps
carrier does not have enough energy to completely interfere with the 3.5 Msps carrier. In most
cases, a carrier as small as this would not be detectable, and the only discernable problem
would be where the Forward Error Correction (FEC) does not compensate for the reduction in
Es/No due to the minor interference.
When both carriers have Carrier ID technology enabled, the MCxD‐100 may be instructed to
look in the spectrum below the composite envelope of the 3.5 Msps carrier to determine if
Carrier IDs are present. Optimally, only a single carrier would be present, but in such
interference conditions, multiple Carrier IDs may be found.
Once an interfering carrier is found, the uplinking station may be contacted and a request made
to disable the identified transmission service.