Over-the-Air Near-Field Test of Antenna Array Using Harmonic Probes on Dielectric Strip Waveguide

A method for testing radiators in an antenna array is presented, which is comparatively simple and allows for parallelization of per-element tests. Diode-loaded dipoles are placed on dielectric waveguide in the near-field of the radiators. The probed signal is frequency-doubled by the diode and then guided by the waveguide to receivers at the strip ends. A proof-of-concept prototype is presented, using patch radiators at 10 GHz and frequency-doubling towards 20 GHz. Measurements show minor influence of the probing setup on the radiators and localization of the active radiator being possible from received signals at both ends of the dielectric waveguide.