RC3000 Antenna Controller | Chapter 3 | Detailed Operation |
3.2.2.3.5 Terminal Peak Up
NOTE: this option is only functional if the mount has been fitted with high resolution pulse or resolver sensors for both the azimuth and elevation axes. This option will not be available on some mounts where the ability to fit high resolution sensors is not available. The performance of this movement depends on whether or not the correct azimuth and elevation pulse scale factors (3.3.1.3.3 and 3.3.1.3.6) have been characterized for the mount.
The terminal peakup option is selected via the AUTOPEAK ON configuration item (3.3.1.2.6).
If an azimuth scan finds a peak, it will return to the azimuth position where it noted the peak. This position may not be the absolute peak position due to the relatively large steps taken during the azimuth scan. If enabled, the terminal peakup option will next perform a “fine tune” peakup. While executing this peakup, line 4 will display “PERFORMING PEAKUP” and the AZIM and ELEV fields will display pulse or resolver counts rather than angles.
During the peakup, small jogs in azimuth and elevation will be made to find the local peak position. These movements will be similar to the Step Track maneuver described in 3.2.2.9.1. The step sizes taken will approximate a theoretical signal strength change of 0.3 dB (according to antenna size, operating band, etc).
3.2.2.3.6 Polarization Tilt Compensation
If enabled via the TILT configuration item in the AUTOPEAK screen (3.3.1.2.6), additional movements in azimuth will be made during the LOCATE function in order to characterize the pitch and roll of the antenna platform.
Rather than going directly to the beginning point for a scan operation, azimuth will be moved to points 90 and 45 degrees away. The elevation axis will not be changed during these moves so the effect of platform pitch and roll can be measured via the inclinometer. During these additional azimuth movements a message such as "DETERMINE TILT: MOVE AZIM TO FIRST POINT" will be displayed on line 4 to indicate that the tilt is being characterized.
After the platform tilt has been characterized, the normal LOCATE sequence will be finished. After reaching the target location, an additional step will be performed to move polarization to compensate for any platform tilt. During this step the message "ADJUSTING POL TO COMPENSATE FOR TILT" will be displayed.
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