28GHz-Band Antenna-Coupled Electrode Electro-Optic Modulator for Receiving Two Orthogonal Polarization Components Simultaneously

We have been studying an antenna-coupled electrode electro-optic (EO) modulator based on an antenna-coupled-electrode on LiNbO
3
-crystal. EO modulators are applicable as a passive wireless-optical signal converter with an integration of planar antenna and are expected to be a key device for the realization of “Massive Machine Type Communications” in Fifth-generation (5G) mobile communication systems. An antenna-coupled electrode EO modulator is also applicable for an EO senser for quasi-millimeter and millimeter wave. In this paper, we report on a new antenna-coupled electrode EO modulator that can receive two orthogonal polarization components simultaneously. The ability to simultaneously receive two orthogonal polarization components is effective for expanding communication capability. The experimental results of good polarization separation, directivity and data transfers are reported.