一种适用于波束扫描的宽带低剖面介质谐振器天线  

A low-profile wideband dielectric resonator antenna suitable for beam-steering applications

作　　者：崔伦雪 范鑫 余洋 杨汶汶[1] 陈建新[1] CUI Lunxue;FAN Xin;YU Yang;YANG Wenwen;CHEN Jianxin(School of Information Science and Technology,Nantong University,Nantong 226001,China)

机构地区：[1]南通大学信息科学技术学院,南通226019

出　　处：《电波科学学报》2022年第5期768-774,共7页Chinese Journal of Radio Science

基　　金：国家自然科学基金(62071256);毫米波国家重点实验室开放课题(K202112);江苏省高校“青蓝工程”。

摘　　要：近年来,为解决传统介质谐振器天线(dielectric resonator antenna,DRA)体积庞大等问题,新颖的低剖面DRA如介质贴片天线和平面介质天线被提出并迅速成为研究热点.然而,现有的低剖面DRA设计要么平面尺寸较大(>0.5λ_(0)×0.5λ_(0)),要么带宽较窄(<10%),限制了它们的实际应用.文中提出了一种具有小型化平面尺寸的宽带低剖面DRA.本天线采用介质贴片设计,顶部为高介电常数的介质贴片,中间为低介电常数的介质基板,底部为缝隙馈电结构.缝隙馈电结构可激励起介质贴片谐振器的基模TE_(111)和高次模TE_(131)两种工作模式,这两种模式的场分布在贴片边缘部分存在基模场强较弱而高次模场强较强的显著区别.本设计巧妙地利用了该区域的模式场强区别,通过略微增加贴片边缘部分高度来显著影响高次模谐振频率而轻微影响基模谐振频率,从而将高次模TE_(131)的谐振频率迅速下拉并与基模TE_(111)的谐振频率靠近合并,在不增大介质贴片平面尺寸的前提条件下获得宽带工作效果.本天线的三维尺寸为0.35λ_(0)×0.35λ_(0)×0.08λ_(0)(λ_(0)为中心频率处的空气中波长),线极化实物案例测试结果表明该天线具有18.5%的−10 dB阻抗带宽以及7.3 dBi的最大增益.该天线平面尺寸小,适用于具有波束扫描功能的阵列天线设计;且提出的设计理念还可进一步拓展应用于圆极化天线设计.Recently,to solve the huge volume of conventional dielectric resonator antenna(DRA),the innovative low-profile DRAs,such as dense dielectric patch antenna(DDPA)and planar DRA,have been developed,and quickly become the hot spots.However,the existing low-profile DRA designs have disadvantages such as large planar sizes(>0.5λ0×0.5λ0)or narrow bandwidths(<10%),which limit their applications.In this paper,a low-profile wideband DRA with a miniaturized planar size is studied.This antenna adopts a dense dielectric patch resonator(DDPR)design,which has a high permittivity dielectric sheet on the top,a low permittivity substrate in the middle,and a slot feeding structure on the bottom.The slot feeding structure can excite two working modes of the DDPR,which are TE111 and TE131,respectively.The two modes have very different field distributions at the edge area of the DDPR,that is the E-field distribution of TE111 is very weak while the E-field of TE131 is quite strong.Based on the observation,we propose a technique of slightly increasing the height of the edge area of the DDPR,which can significantly affect the TE131resonant frequency while slightly affect the TE111 resonant frequency.With this technique,the resonant frequency of TE131 mode can be quickly pulled down and merged with that of TE111 mode.The operating bandwidth,therefore,can be greatly enhanced without increasing the planar size of the DDPR.The size of the antenna is kept as 0.35λ0×0.35λ0×0.08λ0.Measured results show that the linearly polarized antenna prototype has a-10 dB impedance bandwidth of18.5%and a maximum gain of 7.3 dBi.Simulated results of the 1×5 array show that the antenna is suitable for beamsteering applications.Further,the design concept is extended to a design of circularly polarized antenna,which also has a compact size and an enhanced bandwidth.

关 键 词：低剖面 介质谐振器天线(DRA) 宽带 波束扫描 圆极化 

分 类 号：TN820.2[电子电信—信息与通信工程]