Compact bandwidth-enhanced center-fed CPW zeroth-order resonant antenna loaded by parasitic element

Abstract

A low-profile bandwidth-enhanced zeroth-order resonant (ZOR) antenna based on composite right/left-handed transmission line (CRLH-TL) theory loaded by parasitic element is presented in this paper. The bandwidth and efficiency of the proposed ZOR antenna is improved simultaneously by introducing a parasitic element resonating within the CRLH-TL band-stop. The dispersive behavior of the ZOR antenna is analyzed by performing full-wave simulation using CST microwave studio and compared with the theoretical circuit model. The overall dimensions of the proposed antenna is 0.303λ0× 0.248λ0× 0.003λ0. The antenna has been fabricated and tested. The experimental results exhibit wide operational bandwidth of 87.1% and excellent radiation efficiency up to 95.7%. Owing to the symmetrical configuration of the proposed design the polarization purity better than −14 dB is obtained. The measured results are in very good agreement with the simulation. The compact, uni-planar and via-less configuration of the proposed antenna with reasonable polarization purity makes it desirable to be used for modern wireless communication systems such as GSM, UMTS, WiMAX, WLAN and LTE.