Paradise P300 User Manual

Page 158

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P300H

P300 Series Modem Installation and Operating Handbook

Page 158

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Start the AUPC in a passive mode (distant end monitoring only mode) to ensure the system is working:

&

Switch on REMOTE REPORTING (

Change, Rx, Demod, AUPC

) to respond to the Eb/No

requests at the distant modem.

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Set the local AUPC for

Mon Dist

, to determine if it is working correctly. If it is then the distant Eb/No

should be available on the

Monitor, Distant

screens. If the Eb/No or BER figures say “Unavail”

then the ESC is not correctly configured. If it does not work in this mode don’t start changing the
AUPC, sort out the ESC channel !

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When the distant Eb/No is displayed, record the distant Eb/No under clear sky conditions. Then
change the AUPC mode to Maint Eb/No in order to get access to the other AUPC settings.

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Review the proportion of ESC bandwidth and more importantly the distant Eb/No update rate using

Info, View Config, Tx, (down, down etc)

.

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Determine the parameters for the AUPC:

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Determine the way the AUPC will operate, will it try to :

1.

Maintain a minimum Eb/No, but take advantage of a better Eb/No when atmospheric
conditions are favourable (normal)

2.

Maintain a fixed Eb/No, reducing Tx power when atmospheric conditions are favourable
(unlikely).

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To maintain a minimum Eb/No, set this as the

Target Eb/No

, set the

Max power

to the

maximum increase you are allowed, and set

Min power

to Zero. This will prevent the Tx power

decreasing if the Eb/No is better than the target, but will increase the power if the Eb/No falls below
target.

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To maintain a fixed Eb/No set this as the

Target Eb/No

, set the

Max power

to the maximum

increase you are allowed, and set

Min power

to the limit of the power decrease you will accept.

The Tx power will increase and decrease within the limits to try and maintain a constant Eb/No.

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Set the

Tolerance Window

size to something practical, say 0.2 to 0.5dB (depending on how

accurately you wish to try and maintain the Eb/No).

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Set the

Slew Rate

to something which can respond to a fast fade. We suggest no less than

15dB/min (ie 0.25dB/sec) If there is no reason to set a particular slew rate then leave it set to zero
(no slew rate limit).

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Set the

Comms Loss Action

after careful consideration. The most advantageous setting is

Maximum

, but note that anything which interrupts the link will cause the Tx carrier to increase to

the maximum delta Tx power.

Freeze

is probably the most sensible choice, causing the carrier to

remain at the current value until the link is restored. Finally

Nominal

is the safest option, with the

AUPC returning the carrier to it’s nominal power if the link is broken.

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Optionally log the parameters:

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Use the Autolog feature to optionally record the distant Eb/No and/or the AUPC delta power. This
may prove useful in determining how often the AUPC is required, and if it manages to maintain the
Eb/No within the parameters you have set. Logging the AUPC delta power allow you to, if
questioned, be able to specify to the satellite operator the exact power you were transmitting
throughout the day (or at a specific time in question).

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