基于临近耦合馈电的超宽带圆极化天线

Ultra-wideband circularly polarized antenna based on adjacent coupled feed

摘要:

针对通感一体化技术(ISCA)中卫星通信对超宽带、圆极化的需求,提出一款加载弧形枝节的超宽带圆极化微带天线。通过对方环天线进行裁剪处理,调节表面横向电流和纵向电流,以产生圆极化波。加载两个四分之一圆弧型枝节,扩展轴比带宽。通过设计天线底层的临近耦合馈电结构,与天线顶层产生谐振,实现天线小型化,并扩展阻抗带宽。从仿真和测量结果可以看出,天线为右旋圆极化(RHCP)辐射；阻抗带宽(IBW)为9.06-22.55 GHz(85.4%)；3 dB圆极化轴比带宽(ARBW)为9.91-21.54 GHz(74%)；峰值增益为3.5 dBi；尺寸为11.7×11.7×0.127 mm3(0.38λ×0.38λ×0.127 mm3,λ为9.91 GHz对应的自由空间波长)。所设计的天线结构简单紧凑、工作频带宽,覆盖Ku波段。

Abstract:

An ultra-wideband circularly polarized microstrip antenna loaded with arc-shaped branches was proposed for satellite communication in Integrated Sensing and Communication (ISAC). By cutting the square loop antenna and adjusting the surface transverse and longitudinal currents, circularly polarized waves were generated. The axial ratio bandwidth was expanded by loading two quarter arc-shaped branches. By designing an adjacent coupled feed structure that resonated with the top layer of the antenna, achieving antenna miniaturization and expanding impedance bandwidth. The simulation and experimental results show that the antenna has right-handed circularly polarized radiation; The impedance bandwidth (IBW) is 9.06 to 22.55 GHz (85.4%); The 3 dB circular polarization axis ratio bandwidth (ARBW) is 9.91 to 21.54 GHz (74%); The peak gain is 3.5 dBi; The dimension of the antenna is 11.7×11.7×0.127 mm3 (0.38×0.38×0.127 mm3, where λ is the free space wavelength corresponding to 9.91 GHz). The designed antenna structure is simple, compact, and has a wide operating frequency band that can cover the Ku-band.