基于特征模理论的超宽带单极子天线设计

Design of UWB monopole antenna based on characteristic mode theory

对于传统的天线而言,其带宽相对较窄。针对此问题,提出了一种新型超宽带(ultra-wideband,UWB)对称单极子微带天线。根据特征模理论,首先对一款窄带单极子印刷天线进行特征模式分析,结合天线理论,在窄带天线结构上引入渐变结构和矩形槽,使特征模式在目标频段内谐振,并通过馈电激励方式激发出该特征模式,从而使天线带宽得到拓展的同时具有良好的增益。仿真结果表明,基于特征模理论设计的天线具有140.86%的相对带宽,在2.88~16.6 GHz的工作频段内阻抗匹配良好,并且具有良好的辐射性和稳定的增益,其工作频率覆盖UWB频段、无线局域网、射频识别、全球微波互联接入及Ku频段。

In this paper,a novel ultra-wideband(UWB)symmetrical monopole microstrip antenna is proposed.According to the characteristic module theory,firstly,the characteristic mode of a narrow-band monopole printed antenna is analyzed.Combined with the antenna theory,the tapered structure and rectangular slot are introduced into the structure of the narrow-band antenna to make the characteristic mode resonate in the target frequency band,and the characteristic mode is excited by the feed excitation,so that the antenna bandwidth is expanded and the antenna has good gain.The simulation results show that the antenna designed based on the the characteristic module theory has 140.86%relative bandwidth,good impedance matching in 2.88~16.6 GHz frequency band,good radiation pattern and stable gain.Its operating frequency covers the frequency band of UWB,wireless local area network,radio frequency identification and worldwide interoperability for microwave access and Ku bands.