Advanced planar near-field antenna measurements

Abstract

This chapter presents a brief introduction to a number of more advanced and more recently developed topics associated with planar near-field antenna measurements. These include active alignment correction which seeks to improve the accuracy with which the boresight direction of an antenna is known; position correction techniques for improving the flatness and straightness of the sampling grid; non-canonical transforms, phase-recovery which enables measurements to be made where obtaining a direct phase reference would be impractical including testing using drones and industrial robotic systems; microwave holographic metrology which is used for performing non-destructive non-invasive aperture diagnostics; compressive sensing which is used for efficient industrial testing; three-antenna extrapolated gain and polarisation measurements, auxiliary translation and auxiliary rotation which are used to minimise truncation; finishing with the poly-planar technique which is used to mitigate measurement truncation.