Operational Network Specification; Terrestrial Framing - Drop Mode/Insert Mode - Radyne DMD20 Installation And Operation Manual

User Interfaces
n = 1, data rate = 64000
n = 2, data rate = 128000
n = 3, data rate = 192000
n = 4, data rate = 256000
n = 5, data rate = 320000
n = 6, data rate = 384000
n = 8, data rate = 512000
n = 10, data rate = 640000
n = 12, data rate = 768000
n = 15, data rate = 960000
n = 16, data rate = 1024000
n = 20, data rate = 1280000
n = 24, data rate = 1536000
n = 30, data rate = 1920000 (valid with E1 Interface only)

4.6.2 Operational Network Specification

The Network Specification of the Modem often determines which additional menus and displays
are available for use by the operator. The D&I Mode-specific menus will not be displayed unless
the Network Spec. of the modem is set to D&I. Therefore, the second step in configuring the
modem should be to set the Network Spec. to D&I. At this point, the D&I specific menus in the
Interface section will become available and will remain available until the Network Spec. of the
modem is changed to something other than D&I. When the Network Spec. is changed to
something other than D&I, the D&I specific menus will automatically disappear.

4.6.3 Terrestrial Framing - Drop Mode/Insert Mode

The Drop Mode Selection and the Insert Mode Selection identify the Terrestrial Data-Framing
Format. As previously mentioned, their selection is influenced by the Modulator and Demodulator
Data Rates, and trying to select a T1 Type Framing Format with a data rate of 1920000 bps will
result in an error message. In turn, the selection of the terrestrial framing formats influences the
satellite channel to terrestrial timeslot mappings in the following manner:
The selection of T1 -D4, T1-ESF, or SLC-96 type terrestrial framing format limits the
terrestrial timeslots to values from 1 - 24.
The selection of PCM-30 or PCM-30C type terrestrial framing limits the terrestrial
timeslots to values from 1 - 15, 17 - 31. In these modes, terrestrial timeslot 16 is
reserved for ABCD signaling and may not be dropped or inserted.
The selection of PCM-31 or PCM-31C type terrestrial framing limits the terrestrial
timeslots to values from 1 - 31. Therefore, the terrestrial framing format should be
identified via the Drop Mode and Insert Mode entries prior to editing the Drop or Insert
satellite channel to terrestrial timeslot maps.
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DMD20 Universal Satellite Modem
TM103 - Rev. 1.1