Structural Correction of a Spherical Near-Field Scanner for mm-Wave Applications
Authors: Daniël Janse van Rensburg & Pieter Betjes
A spherical near-field test system allowing for the antenna under test to remain stationary during testing is described. The system is suitable for use at mm-wave ( > 50 GHz) frequencies. Fidelity of the structure for testing at these frequencies is critical and since the structure experiences a gravitational force as a function of probe position, a complex deformation map results. There is also a radial distance variation of the probe and a technique to correct for this variation (presented before) is expounded upon. We describe the structural perturbation observed on such a scanner and assess to what extent this limits high frequency application for spherical nearfield testing.