Doubletalk Carrier-In-Carrier Option; Figure 3-12. Dmd2050E Handheld Key Loader - Comtech EF Data DMD-2050E Installation And Operation Manual

DMD2050E Universal Satellite Modem
3.11

DoubleTalk Carrier-in-Carrier Option

WARNING
Before you commission a satellite link with Carrier-in-Carrier, make sure that the link
is sufficient for normal operation and all system settings are correct. Incorrect link
setup has an unwanted effect on the system.
Space segment costs are typically the most significant operating expense for any satellite-based
service, having a direct impact on the viability and profitability of the service. For a satellite
transponder that has finite resources in terms of bandwidth and power, the leasing costs are
determined by bandwidth and power used. Therefore, a satellite circuit should be designed for
optimal utilization to use a similar share of transponder bandwidth and power.
The traditional approach to balancing a satellite circuit – once the satellite and earth station
parameters are fixed – involves trade-off between modulation and coding. A lower order
modulation requires less transponder power while using more bandwidth; conversely, higher
order modulation reduces required bandwidth, albeit at a significant increase in power.
Comtech EF Data has added a new dimension to satellite communication optimization:
DoubleTalk Carrier-in-Carrier.
MN-DMD2050E Revision 2

Figure 3-12. DMD2050E Handheld Key Loader

Theory of Operation
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