Functional Descriptions; Drop Only; Insert Only; E.4 Functional Descriptions - Comtech EF Data DMD-2050E Installation And Operation Manual

DMD2050E Universal Satellite Modem

E.4 Functional Descriptions

E.4.1 Drop Only

When Drop is enabled and Insert is disabled, the unit 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 (see
Figure E-3).

E.4.2 Insert Only

When Insert is enabled and Drop is disabled, the unit 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 (see Figure E-4).
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 (see
Figure E-5).
MN-DMD2050E Revision 2
Figure E-3 Drop Only
Efficient Drop and Insert
E–4