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7.5.2.4
Initializing Sensors
Now that the azimuth and elevation are in the proper homed position, the precision feedback
encoders are initialized based on the analog sensor position. From this point forward, axis
movements are based on the motor encoders and analog inputs are used to signal an alarm in the
event a sensor fails or the readout is incorrect.
7.5.2.5
Compass Read
The system will then move to the predefined azimuth/elevation compass read positions. Typically
this is where the Electronic compass is level. This reading is a coarse heading the system will use to
reduce time searching for the target satellite. Once the system is in the correct orientation for data
collection from the compass, the system reads the value from the compass and generates a heading
based on the reading. Once the heading is generated, the system creates a series of azimuth and
elevation points that are tilt compensated according to the pitch and roll values taken during the
‘Home’ command. The points are based on a compass scan width where the width is set to
compensate for any compass error.
Command Response Message: Read Compass
7.5.3 Acquisition Sequence
Any Acquisition command will use parameters selected in the active profile for the current target.
The following steps are common for all types of Acquisition. If a home has not been performed prior
to the acquire routine, the unit will automatically home first before taking acquiring.
7.5.3.1
Move to Initial Scan Point
The positioner now moves to the initial scan point (first point of the tilt compensated azimuth and
elevation values). The polarization is moved to a calculated value based on the electronic compass
heading.
