s80HD WorldView™ – Marine Satellite Television System
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-3°
-2°
-1°
0°
1°
2°
3°
1
5
10
15
20
30
25
Search 1 (Gyro Free) Search Pattern
Search 3 pattern
Elevation
(EL) Range
step size
Azimuth (AZ) Range
Search 3:
A search pattern 3 will automatically be initiated after Search 1 or Search
2 mode. In Search 3 mode, the antenna will search for the target satellite by turning
its azimuth angle directly to the position calculated using the ship’s heading input
and lock onto the satellite. If the desired signal is found and above the predefined
tracking level, the ACU will terminate Search 3 and go into TRACKING mode.
Search is conducted in a two-axis pattern consisting of alternate movements in
azimuth (AZ) and elevation (EL) as forming expanding square indicated as below
diagram.
Target Satellite EL Position
Revolution (AZ direction)
Target EL Angle
Turn 1
Target EL Angle + 0.5°
(or defined step size)
Turn 2
Target EL Angle -0.5°
(or defined step size)
Turn 3
Search 1 antenna motion
