一种宽频带高增益高极化隔离度的微带天线

Broadband microstrip antenna with high gain and high cross-polarized isolation

设计了一种具有高增益、高极化隔离特性的宽频带层叠型E形天线。通过激励E形辐射体，获得双峰谐振回路，并在E形天线上方附加寄生元，构成了三峰谐振特性，从而取得较传统E形天线更宽的频带；通过E形天线在低端激励的双电流路径保证了天线在频率低端的高增益特性，而天线本身的辐射体尺寸保证了频率高端的高增益特性。采用Ansoft HFSS电磁仿真软件对提出的天线模型仿进行优化，依次在1．75GHz，2．1GHz，2．475GHz形成了三个谐振峰值；在1．7-2．54GHz内驻波比≤1．5，其相对带宽达40％，在1．7～2．5GHz频带内增益〉8dBi，且具有低达-55dB的优异交叉极化特性。

A broadband E-shaped stacked antenna is presented with high gain and high cross-polarized isolation. Threepeak resonant circuit is generated by adding a rectangular element above the E-shaped antenna with dual-peek resonant tank for impedance bandwidth improving. Dual currents at the low frequency band ensure its high gain characteristic, while the size of radiator of antenna present a sufficient aperture for the gain at high frequency band. Simulation and optimization of the antenna characteristics is carried out by Ansoft HFSS. Results show that three resonant frequencies are generated in the proposed antenna at 1.75 GHz, 2.1 GHz, 2.475 GHz,respectively. The antenna achieves a 40% impedance bandwidth of VSWR≤ 1.5 operating at 1.7-2.54 GHz. At the frequency band of 1.7-2.5 GHz, gain of 〉8 dBi and cross-polarized isolation〈-55 dB are obtained for mobile communication antenna.