Alignment of a Large Spherical Near-Field Scanner using a Tracking Laser Interferometer
Authors: Scott Pierce, Charles Liang
Publication: AMTA 2003
Copyright Owner: NSI-MI Technologies
In this paper, we describe the process used to align a large spherical near-field test system. The probe positioner consists of a cantilevered arc design with a probe path radius of five meters and a scan angle of 180°. The AUT positioner consists of an MI Technologies Model 51230 azimuth positioner with a high-precision encoder. The system is aligned using an SMX Tracker 4000 tracking laser interferometer.
Alignment into a spherical system is achieved by initially defining two cylindrical systems; a primary probe positioner based system and a secondary, AUT positioner based system. Sources of mechanical error in each of these systems are identified and techniques used to control these error sources are described.