Near-Field Electro-Optic Measurement for Multiphysics Analysis of THz Antennas

In this paper, we propose a novel approach using near-field electro-optic measurements to evaluate the impact of mechanical deformations that must be considered in the multiphysics design of THz systems.Unlike conventional microwave systems, THz systems feature much shorter wavelengths, making them highly sensitive to even minute mechanical displacements.By measuring the near-field phase distribution of the antenna, our method enables accurate quantification of the effects that structural deformations-such as twisting or shifting of the antenna aperture-have on the radiation pattern.Focusing on a 40 dBi, 300 GHz high-gain antenna (FWHM: 1.4 degrees), we demonstrated that a beam tilt of 0.17 can be detected using this technique.