高隔离度双极化SIC微带天线设计

为了提高双极化天线的隔离度,在缝隙耦合微带天线的基础上,提出了一种增强双线极化天线隔离度的新方法.该方法借鉴基片集成波导技术的思想,将基片集成金属过孔嵌入到缝隙耦合双线极化微带天线当中,在馈电层实现了双端口馈电的区域独立,提高了天线的隔离度;同时对整个天线通过基片集成金属过孔的嵌入,增强了天线的容性特征,减小了天线等效阻抗的虚部,极大地改善了双极化天线的匹配效果.通过Ku频段的双线极化天线设计实例,验证了这种方法的有效性.仿真结果表明,嵌入基片集成金属过孔的双极化天线隔离度比传统天线的隔离度提高了56%以上,对于-20dB的反射系数标准,天线的带宽拓展了110%以上.

Design of the dual polarized SIC microstrip antenna with high isolation

A novel method for enhancing the isolation of dual-linear polarized antenna is proposed based on the aperture coupled structure. The substrate integrated waveguide (SIW) technology is introduced and the substrate integrated cavities (SICs) are used in the aperture coupled and dual-linear polarized antenna to enhance the isolation between two ports in the feeding layer. The capacitive characteristic for the proposed antenna is improved and the imaginary part of the equivalent impedance for the proposed antenna is decreased by embedding the SICs in the four sides of the dual-linear polarized antenna, so that the impedance bandwidth of the proposed antenna is improved. A Ku band dual-linear polarization microstrip antenna is designed by this method to prove the effectiveness of the method and simulated results indicate that the isolation is enhanced above 56％ and the impedance bandwidth is increased above 110％ of the reflection coefficient smaller than -20dB. Experiments are carried out to verify the simulations.