Testing electrically small antennas with using a fiber optic to RF transducer

The paper presents how the effect of the coax cable can be resolved when testing electrically small antennas in a multi-probe antenna measurement system [1]. The MVG StarLab15 system setup was used for such testing activity. It was equipped with a fiber optic to RF transducer which was directly connected to the AUT (Antenna under Test). The StarLab15 was validated in terms of its system performances when using the transducer in place of the coax cable. The fiber optic to RF transducer is 20×23.5×10mm in size and it is powered by a DC voltage through a fiber optic. Not-chocked monopole antennas were used as AUTs at 1GHz and 2GHz resonance frequency. Comparison between the FoMs measured with using metallic coax cable, EMI dressed coax cable and fiber optic to RF transducer is also reported. This work was done by using the INSIGHT SW tool [2] which allowed in reconstructing the current distributions of the antenna from the measured data.