Radyne DMD2050, Operation Manual

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DMD2050 Universal Satellite Modem Theory of Operation
TM110 – Rev. 1.3 3-15
3.10.1 Drop Only
When Drop is enabled and Insert is disabled, the DMD2050 performs a drop-only function.
Framed E1 or T1 Data is input via the Send Data In Port, the selected timeslots are dropped into
the IBS frame structure, and the unaltered terrestrial data is output via the Send Data Out Port
(refer to Figure 3-12).
Figure 3-12. Drop Only
3.10.2 Insert Only
When Insert is enabled and Drop is disabled, the DMD2050 performs an insert-only function. If
framed terrestrial E1 or T1 Data is available, it should be input via the Insert Data In Port. The
Terrestrial Data is buffered inside the Modem. The RX Baseband Processor inserts satellite data
into the selected timeslots in the G.704 Frame and the modified terrestrial data is then output via
the Receive Data Out Port (refer to Figure 3-13).
If framed terrestrial data is not available, selection of the Internal T1/E1 frame source will cause
the modem to generate the required G.704 Frame. The Satellite Data will be inserted into the
selected timeslots, and the resulting terrestrial data will be output via the Receive Data Out Port.
Any non-inserted timeslots in the G.704 Frame will be filled with the appropriate Idle Code (refer
to Figure 3-14).
Figure 3-13. Insert Only with Eternal Frame Source