Comtech EF Data CDD-880, Installation And Operation Manual

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CDD-880 Multi Receiver Router MN-CDD880
Appendix D Revision 2
D–17
when dynamic routing mode is enabled, the ACM, CDRP, and data traffic statistics
messages sent to the CTOG-250 maintain the forward path ACM and routing tables.
o
Offline – In this ECM state, the CDM-840 does not transmit and remains idle until a new
ECM state is selected either locally or from the VMS. Examples for use of this particular
ECM state are COTM (communications on the move) or military maneuvers providing
radio silence conditions.
Click
[Submit]
to save.
•
Multicast IP: – Enter the IP address for the Multicast of the Transmission Announcement
Protocol (TAP) message that is sent out by the CDD-880 to all of the associated CDM-840s in
that group.
•
Group ID: (0 to 255) – Enter the Group ID number for the CDD-880 to which this unit
belongs.
• Power Hunt Enable:
– Use the drop-down list to select this function as
Disable
or
Enable
.
When enabled, the transmission power control feature for the unit modulator is activated
while in Entry Channel Mode (ECM). This function provides compensation during periods of
impaired transmission or for instances when the initial (baseline) power value is insufficient,
and assists in maintaining return link integrity.
•
Rx LO Frequency: – Assign a value, in MHz, to the Rx LO (Low Oscillator) Frequency.
• Tx LO Frequency: – Assign a value, in MHz, to the Tx LO (Low Oscillator) Frequency.
• ECM Power:
(-40.0 to 0.0) – Enter the power level, in dBm, for transmission of the ALOHA
ECM signal. This level was determined for this unit when its terminal was commissioned,
and must be calibrated with the satellite provider.
Click [Submit] to save.
ECM Remote Status
This section provides the following read-only information:
•
Cycle Length: – The Cycle Length is the total length of time, in milliseconds, between the
start of a transmission and the completion of the transmission cycle (TAP) transmitted by
the CDD-880 to the CDM-840s in the ECM group. It is the product of the number of slots and
the slot length (consisting of the preamble, data slot size, and guard band).
•
ALOHA State: – The ALOHA State indicates the current state of this unit during the ECM
cycle:
o
Idle – The unit is not transmitting; either inactive or waiting for switching assignment.