A uniplanar quasi-Yagi antenna with wide bandwidth and low mutual coupling characteristics

Abstract

We report for the first time a planar quasi-Yagi antenna printed on a single layer of high dielectric constant substrate (Durold, /spl epsiv//sub r/=10.2) which measures 48% bandwidth (VSWR<2). The antenna radiates an end-fire beam, with a front-to-back ratio >15 dB and cross-polarization level below -12 dB across the entire frequency band. A very low mutual coupling level of below -22 dB has been measured for a two-element array with /spl lambda//sub 0//2 separation.