COBHAM SAILOR 600 VSAT Ka, Руководство по установке

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Calibration
98-148248-A Chapter 6: Configuration 6-13
Confi
guration
6. Click
Start
. Once commissioning is completed the antenna will search for the I5 satellite
with the highest elevation.
7. The antenna will find the satellite and the modem will perform necessary steps to enter
the network (software upgrades, if available).
8. The Unified Web Interface of the Core Module will indicate the modem in the network
as well as the modem status in the display in the menu
MODEM
.
9. When commissioning is completed, test all subscribed services.
6.3.5 Operation in gyro-free mode
If input from a gyro compass is not available (Heading input: none), information from the
GPS position is used when searching for a satellite. When the antenna does not have ship
heading input from the vessel's gyro compass, the azimuth direction of the satellite is not
known. In this case the antenna will start a 360 degrees sky scan and scan until it finds a
satellite. The satellite search time to find the satellite and start tracking is therefore raised
considerably. If the ship is on a steady course and sails at a speed over ground above 5 kn,
the system can use an estimated heading from the current GPS position. This will reduce
the search time, but it will still be a longer search time than with heading input.
If a system loses the signal from the satellite, i.e. due to blockage, and the duration of signal
loss is longer than approximately 1 minute, a system without heading input must do a new
sky scan to find the satellite when the antenna is out of blockage.
6.3.6 Fixed TX IF principle
The SAILOR 600 VSAT Ka uses a TX IF gain concept. After calibration it provides a fixed
average gain from the TX-port of the ACU to the input of the BUC. Advantages of the fixed
TX IF gain principle are:
• Average TX IF gain independent of antenna cable length
1
• Compatibility with the TX Power control feature
When installing the SAILOR 600 VSAT Ka you make a cable calibration. At that point every
installation adjusts to the same average TX IF gain regardless of the ADU cable length.
Additionally the SAILOR 600 VSAT Ka system also compensates for variations of the cable
characteristics or loss over frequency.
1. You find the maximum allowed cable loss at Prerequisites on page 3-16.
SAILOR600Ka-IM-98-148248.book Page 13 Monday, November 23, 2015 1:36 PM