CDM-750 Advanced High-Speed Trunking Modem
Revision 2
Appendix G
MN-CDM750
G–2
•
The
arrows
in
the
diagram
indicate
the
direction
of
data
flow;
while
data
flow
between
Blocks
1
and
2
is
valid
,
data
flow
between
Blocks
2
and
1
does
not
occur
.
Arrows
on
both
ends
of
a
link
show
where
data
flow
is
bidirectional
.
Name
Function
LAN Region
This unmarked region of the diagram refers to the LAN – the source / destination for data traffic.
The information of interest is tailored to Ethernet interfaces, so most of the statistics do not apply
to the G.703 interface.
Block 1 – Ethernet Switch
The LAN’s access to the modem is at the Ethernet switch. There are two RJ-45
10/100/1000BaseT ports and one optional optical Gigabit Ethernet (SFP module) port available
at the rear of the modem.
Block 2 – Terrestrial Port
Processor (Tx)
Data from the LAN destined to the satellite flows into this block.
Block 3 – Expansion Slot
This is reserved for future plug-in modules.
Block 4 – Terrestrial Port
Processor (Rx)
This is the counterpart to the Tx processor. It forms Ethernet packets and forwards them to the
Ethernet Switch.
Block 5 – Deframer
The data from the satellite frames is recovered.
Block 6 – Framer
Data processing to assemble data into frames for the modulator is performed in this block.
Block 7 – Modulator
Frames are mapped into the appropriate FECFrame and mapped into the selected ModCod for
transmission to the satellite.
Block 8 – CnC
Signals to and from the satellite are processed here to cancel the locally transmitted carrier and
receive the carrier from the distant end.
Block 9 – Demodulator
Carriers received from the satellite are processed here to recover data frames.
Block 10 – µP / M&C /
Management
The microcontroller (µP) is involved in collection and calculation of statistics.
IF Region
This unmarked region of the diagram refers to data to or from the satellite link.
Figure G-1. CDM-750 Data Flow Diagram
Summary of Contents for CDM-750
Page 76: ...CDM 750 Advanced High Speed Trunking Modem Revision 2 Updating Firmware MN CDM750 4 12 Notes...
Page 224: ...CDM 750 Advanced High Speed Trunking Modem Revision 2 Appendix A MN CDM750 A 4 Notes...
Page 234: ...CDM 750 Advanced High Speed Trunking Modem Revision 2 Appendix B MN CDM750 B 10 Notes...
Page 256: ...CDM 750 Advanced High Speed Trunking Modem Revision 2 Appendix C MN CDM750 C 22 Notes...
Page 280: ...CDM 750 Advanced High Speed Trunking Modem Revision 2 Appendix D MN CDM750 D 24 Notes...
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