A Planar Quasi Yagi-Uda Antenna Designed For Liquid Crystal Based End-Fire Phased Arrays

摘要

This paper presents a planar quasi Yagi-Uda antenna based on liquid crystal (LC) technology for millimeter-wave applications. The antenna is built on the inner surfaces of two parallel glass substrates, with thin layer of LC filled in the feed part. It is fed by a two-step coaxial-to-microstrip transition. The antenna achieves a measured bandwidth of 31 % with a VSWR < 2, better than 15 dB front-to-back ratio, better than –13 dB cross polarization and 9.0 dBi gain at 28 GHz. Measured scattering parameters, as well as far field patterns agree very well with the simulation results. The planar quasi Yagi-Uda antenna is compatible with existing planar reconfigurable feed network based on LC technology, complementary to the broadside radiating array.