Comtech EF Data MDX420 SkyWire Manual - Manual (Page 68)

MDX420 SkyWire™ Satellite Network Gateway SkyWire Controller (GUI)
MN-MDX420 Revision 6 7–12
Figure 7.4.1.4 AUPC Configuration
Theory of operation: Fade conditions can happen for numerous reasons such as uplink rain
fade, downlink rain fade, antenna mispointing, LNB failure, BUC failure, cable run issues,
temperature etc. The purpose of SkyWire’s AUPC is to try and mitigate the effects of UPLINK
fade ONLY. The reason we do not want to mitigate the effects of downlink fade is due to the fact
that SkyWIre is designed to work in a MESH environment so compensating for one site’s
downlink fade will overdrive the uplink power and the system will be using more of the satellite
power resources than the satellite operator would typically allow. Further to this point increasing
the uplink power to compensate for one site’s downlink rain fade would negatively impact all sites
that did NOT have downlink fade. The purpose of SkyWire’s AUPC is to attempt to illuminate the
satellite with a constant or near constant power and to overcome uplink rain fade. The use of
AUPC is a site by site selection, some units in the share may use this while others in the same
share group may not. AUPC only effects the TX power of the device being configured to use
AUPC and the demodulator RX level is only reading the level of it’s own burst not the RX level of
other sites or an average of all sites in the share group.
Operation: Once the network is up and running in a stable environment and all carrier levels
and Eb/No levels are within the operational range desired (see section 7.6.1 Demodulator
Status Screen) AND the site in which AUPC is to be turned on is in CLEAR SKY
CONDITIONS the user should follow these instructions in this exact order:
1) Click on the “Set Ideal Conditions” button. When this button is clicked, the “Ideal TX
Power Level (dBm)” and “Ideal RX Power Level (dBm)” fields will populate with the
present values of the modulator’s TX power setting and the demodulators Carrier Level
reading. NOTE: If the actual values of the demodulator and modulator are NOT set
when doing this or if the values stay at their default (0.0 dBm TX and -45 dBm RX) this
means that the present conditions of the demod are NOT within SkyWire’s specification
and AUPC SHOULD NOT BE USED. You will also see an event in the event log stating
“INVALID AupcIdealRXCarrierLeveldBm”. If you get this message in the Event Log DO
NOT USE AUPC.
2) Set the TX % Fade figure to a number between 50 and 90 (more on this below).