Comtech EF Data Vipersat SLM-5650A, Инструкция по установке и эксплуатации

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SLM-5650A Satellite Modem
Revision 10
Appendix H G–4 MN-SLM-5650A
Figure G-1. Conceptual Block Diagram
In a number of ways, CnC carriers behave similar to conventional carriers in satellite links. Both
are exposed to adjacent carriers, cross-polarization, and rain fade, and exhibit impairments when
any of these become too great. CnC additionally operates in an environment where:
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Carriers intentionally occupy the same spectral slot, and
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Performance depends upon desired and co-located interfering carrier. The interfering
carrier is canceled, leaving the desired carrier for demodulation.
G.2.1 Operational Recommendations
The rules for CnC operation are summarized as follows:
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Both earth stations share the same footprint so each sees both carriers.
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CnC carriers are operated in pairs.
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One outbound with multiple return carriers is not allowed.
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Asymmetric data rates are allowed (no restrictions).
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The ratio of power spectral density is normally less than 11 dB.
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CnC operates with modems – not modulators only or demodulators only.