State-of-the-art Near-field Measurement System
Author: Karl Haner, Greg Masters
Publication: AMTA 1995
Copyright Owner: NSI-MI Technologies
Planar near-field measurements are the usual choice when testing phased array antennas. NSI recently delivered a large state-ofthe- art near-field measurement system for testing a multi-beam, solid state phased-array antenna. The critical sidelobe and beam pointing accuracy specifications for the antenna required that special attention be paid to near-field system design. The RF path to the moving probe was implemented using a multiple rotary joint system to minimize phase errors. Additional techniques used to minimize system errors were an optical probe position correction system and a Motion Tracking Interferometer (MTI) for thermal drift correction.