RC3000 Antenna Controller

Chapter 2

Installation

The azimuth scale factor is obtained by noting the difference in the azimuth pointing solution angles between two satellites and the pulse counts when on the satellites. For best results, use satellites that are as far apart as possible and make sure you have positively identified the satellites.

Example : Kansas City (38’56N,94’45W) heading of 180.0

SATELLITE

AZIMUTH POINTING

PULSE

 

SOLUTION ANGLE

COUNT

SPACENET 2 (69.0W)

-37.5

33333

SATCOM C5 (135.0W)

53.4

11000

Difference

90.9

22333

(22333 / 90.9) * 57.29 = 14075 pulses/radian

SCALE FACTOR FOR RESOLVER SYSTEMS

The RC3000 uses the actual digitized resolver count in the same way it uses a pulse count. The RC3000 utilizes a 16 bit resolver to digital converter which generates a count value from 0 to 65,535. Typically the resolver sensor rotates with the antenna. The resulting “pulse scale factor” therefore is:

65536 reslover counts / ( 360 degrees * 1 radian/57.29 degrees) = 10430.2 “pulses” / radian

The default scale factor for a resolver system is therefore rounded up to 10431.

The constants are entered via the azimuth pulse drive (3.3.1.7) and elevation pulse drive (3.3.1.10) configuration item screens.

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