基于共面波导馈电的三频单极子天线

摘要

本文提出了一种新型的三频单极子天线,该天线用共面波导(CPW)馈电,由两个不同长度和结构的单极子构成,长单极子结构实现谐振频率1.57 GHz 和3.5 GHz,短单极子结构实现谐振频率2.4 GHz.同时,通过在左侧接地面上增加一个正方形贴片,改善了三个频段内的峰值增益.所实现的天线尺寸为59 mm×40.55 mm×1.6 mm,在三个工作频率上的带宽分别为254 MHz (1.518 GHz~1.772 GHz)、461 MHz (2.289 GHz~2.75 GHz)和226 MHz (3.514 GHz~3.714 GHz),覆盖了 GPS、无线局域网(WLAN)和无线接入系统等频段,增益分别为2.15 dBi,3.12 dBi和3.86 dBi.%In this paper,a novel compact monopole antenna fed by a coplanar waveguide (CPW)for tri-band applications is presented.It comprises two different monopoles and can operate at three resonant frequencies of 1.57 GHz,2.4 GHz and 3.5 GHz.The resonant frequency 1.57 GHz and 3.5 GHz are controlled mainly by the longer monopole and 2.4 GHz is mainly decided by the shorter monopole.In order to improve the gain of the antenna,a rectangular patch is added on the left side of the ground plane.The realized antenna has a total size of 59 mm×40.55 mm×1.6 mm.The bandwidth at three frequencies are 254 MHz (1.518 GHz~1.772 GHz),461 MHz (2.289 GHz~2.75 GHz)and 226 MHz (3.514 GHz~3.714 GHz)respectively,covering the band for GPS,WLAN and wireless ac-cess system.The gains are 2.15 dBi,3.12 dBi and 3.86 dBi respectively.