Aupc - Between Two Modems - Comtech EF Data SNM-1001L Installation And Operation Manual

SNM-1001L Satellite Modem
Automatic Uplink Power Control
With Local AUPC On, set modems (A and B), if modem A loses carrier:
1. Modem A sets its output power (MAXIMUM, MINIMUM, OR HOLD) as specified by
LOCAL CL ACTION.
2. Modem A then sends a "lost carrier" command to modem B.
3. Modem B sets its output power (MAXIMUM, MINIMUM, OR HOLD) as specified by
REMOTE CL ACTION.
4. Once modem A has reacquired the carrier, it sends commands to modem B to achieve the
desired E
decrease power to maintain modem B's target E
Notes:
1. Modem B will not make changes to modem A if the E
2. Modem B will not control modem A transmitting output level if the target noise
3. Modem A will be transmitting at the maximum output if the local carrier loss
4. Caution shall be observed when setting the target E
5. Local carrier loss always takes priority over remote carrier loss.
6. The RX AUPC link is dead when the carrier is lost.
10.2.1 AUPC – Between Two Modems
This mode of AUPC operation allows each of the two modems to operate in a closed link
to control the output of the other modem in a manner that preserves a target Eb/No.
Overhead Card
TX and RX Reed-Solomon
Cards
Selecting ASYNC from the Modem Type menu when the Overhead Card is installed or
by selecting AUPC from the Modem Type menu the Reed-Solomon cards are installed
enables APUC operation. The Modem type is located under the Utility: Modem Type
menu.
To operate, AUPC is enabled on both modems and they are setup as described in
Table 10-1.
/N . During this time, modem B sends commands to modem A to increase or
b 0
target noise.
for modem B is set within 15.5 to 16.0 dB and the receive signal to the modem is
sufficient that the receive noise is 16 dB or better.
action is set to maximum.
maximum limit is established at 16.0 dB.
Hardware
ASYNC/AUPC. This provides AUPC and an ASYNC channel.
AUPC. An ASYNC channel is not available.
/N .
b 0
Corresponding Software (FAST)
10–4
Revision 1
MN/SNM1001L.IOM
/N is within 0.5 dB of the
b 0
/N above 15.5 dB, the
b 0