不完整带隙结构在微带天线中的应用

Application of new defected EBG structure in microstrip antenna

为了使微带贴片天线满足导航和通信等应用设计的某些特殊要求,提出了一种可改善微带天线性能的不完整电磁带隙结构:首先在普通的切去两个对角的方形圆极化贴片天线周围一定距离处附加电磁带隙结构,使谐振频率增加而带宽变化不大;然后,在此基础上又将接地板外侧四边切去窄方形金属层,从而形成方形环介质层.仿真结果表明:新型结构可提高传统贴片天线的低仰角增益和总增益,同时可使传统微带天线较好地实现双频工作.

In order to meet some specific application requirements for mierostrip patch antenna in naviga- tion and communication project, a novel defected electromagnetic band-gap （EBG） and ground structure designed for improving the performance of traditional mierostrip patch antenna was presented. For building this structure, several EBG elements were firstly placed near a usual circularly polarized square mierostrip patch with two opposite corners cut. This can enhance the resonance frequency and change only slightly the band- width of the patch antenna. Then a thin square metal layer was cut off from four sides of the ground plane to forms a square loop of dielectric layer. The results of numerical simulation show that the new structure is able to improve the perforrnanee of antenna gain including total and low elevation situation, and the mierostrip patch antenna equipped with this structure can he treated as a dual-frequency antenna.