Element-level Electric-field Measurement of Phased Array Antennas using Electro-optic System for mm-wave 5G Communications

Abstract

This paper proposes an improved electric-field measurement method for phased array antenna calibration. For free space calibration of array antenna, the complex excitation coefficients for each antenna is determined from the measured amplitude and phase data, and each individual element can be individually compensated for to correct the amplitude and phase errors. A highly stabilized planar field imaging system with dual electro-optic sensors is developed to measure the phase in the reactive near-field region of an array antenna. Experimental results of the electric field of an array antenna operating at 28 GHz are shown to validate the performance of the proposed electro-optic system.