新型双频全向Alford环微带天线

基于无线通信系统对极化分集的应用需求,提出一种新型双频水平极化全向Alford环天线。该天线由2个环形辐射结构构成,外环辐射结构包含4个微带偶极子阵列,谐振频率为2.45 GHz;同时新增耦合圆环内辐射结构,谐振频率为5.225 GHz。实测结果表明,该天线在802.11b (2.40～2.48 GHz)和802.11a (5.15～5.35 GHz)频率范围内S11优于-10 dB,其中在2.45 GHz和5.225 GHz的S11分别达到-17.9 dB和-27.2 dB。由于具备良好的水平极化全向辐射特性,该天线可作为极化分集天线单元应用于无线局域网(WLAN)多输入多输出(MIMO)系统中。

A Novel Dual-band and Omni-directional Alford Loop Microstrip Antenna

Based on the requirements of wireless communication system on polarization diversity,this paper proposes a novel dual-band and horizontal polarization omni-directional Alford loop antenna.This novel dual-band antenna is composed of such two loop radiators as outer loop radiator including four microstrip dipole arrays with resonant frequency of 2.45 GHz and the inner coupling loop radiator with resonant frequency of 5.225 GHz.The practical test results show that this antenna can cover 802.11b(2.40~2.48 GHz)and 802.11a(5.15~5.35 GHz)bands with the S 11 better than-10 dB.The measured S 11 of-17.9 dB and-27.2 dB are achieved at 2.45 GHz and 5.225 GHz respectively.Because the antenna has better omni-directional horizontal polarization,it can be used for polarization diversity of Multi-Input-Multi-Output(MIMO)systems in Wireless Local Area Network(WLAN)applications.