Mocomtech CDM-QX - Manual (Page 34)

CDM-Qx/QxL Multi-Channel Satellite Modem with DoubleTalk™ Carrier-in-Carrier® Revision 7
Introduction MN/CDMQx.IOM
1–10
To accomplish this, either the EDMAC or D&I++ or ESC++ framing types may be used, and the
distant end modem constantly sends back information about the demodulator Eb/No using
reserved bytes in the overhead structure. Using the Eb/No, the local modem adjusts its output
power, and a closed-loop feedback system is created over the satellite link.
A benefit of this AUPC feature is that the remote demodulator’s Eb/No can be viewed from the
front panel display of the local modem.
See Chapter 7. Automatic Uplink Power Control (AUPC) for further information.
1.3.10 EDMAC
To facilitate network management for small networks, the CDM-Qx/QxL incorporates the
proprietary Embedded Distant-end Monitor And Control (EDMAC). In this mode, an additional
5% overhead is combined with the traffic data, (1.6% in Turbo BPSK modes, Turbo Rate 21/44
QPSK/OQPSK, and all data rates greater than 2 Mbps). M&C information is added (transparent
to the user), allowing access to the distant-end modem.
In addition, EDMAC-2 uses 1.6% overhead in all modes for those applications where the 5%
overhead is excessive. The EDMAC and EDMAC-2 modes do not require any additional cabling
at either the local or distant-end Modems. Access to EDMAC is via the standard M&C control
port. Full monitor and control is possible, and the on/off status at the distant-end carrier can be
controlled.
See Chapter 9. EDMAC CHANNEL for further information.
1.3.11 Flash Upgrading Modem Firmware
The internal firmware is both powerful and flexible, permitting storage and retrieval of up to 10
different modem configurations. The modem uses ‘flash memory’ technology internally, and new
firmware can be uploaded to the unit from an external PC. This simplifies software upgrading,
and updates can be sent via the Internet (using the CDM-Qx/QxL Web Server Interface), e-mail,
or on CD. The upgrade can be performed without opening the unit, by simply connecting the
modem to the USB port or Ethernet port of a computer.
See Chapter 4. FLASH UPGRADING for further information.
As of July 2008, Comtech EF Data began incorporating an enhanced flash memory
chip into its chassis design. To accommodate this design upgrade, units that
employ the original vs. the currently-used flash memory chips are identifiable by
the installed Firmware Version.
Observe the following:
• Original chassis = units typically manufactured prior to July 2008: Firmware
No. FW/11245 (Version 1.X.X ↑ )
• Upgraded chassis = units typically manufactured from July 2008 to present:
Firmware No. FW-0000107 (Version 2.1.1 ↑ )
Note that, while the functionality of the two firmware versions is transparent to the
user, these firmware products may
not
be cross-utilized. Always be sure to
identify the chassis in use by its installed firmware prior to attempting any firmware
flash upgrade, then download the appropriate firmware as needed.