正交缝隙耦合馈电宽带圆极化微带天线设计

为了实现圆极化微带天线的频带拓宽和增益提高,在缝隙耦合天线的基础上,设计了一种Ku频段正交缝隙耦合馈电的宽带圆极化微带天线。该天线以双层方形贴片为辐射单元,在拓展天线阻抗带宽的同时提高了增益;采用微带线结合正交左旋缝隙结构实现耦合馈电,通过优化缝隙结构改善了天线轴比特性。测量结果表明:阻抗带宽(VSWR2)和轴比带宽(AR3dB)分别达到22.5%和16.2%,轴比带宽内天线增益均大于9dBi。该结构天线以其简单的馈电设计为宽带圆极化微带天线设计提供了一定的参考价值。

Design of Wideband Circularly Polarized Microstrip Antenna Fed by Orthogonal Slots

On the basis of aperture coupled antenna, a wideband circularly polarized microstrip antenna coupled by orthogonal slots is designed in Ku band to broaden the bandwidth and improve the gain. In the antenna a layered structure with two square patches is taken as radiating elements, so the gain is improved with the broadening of the bandwidth. Coupling feedstructure is realized by adopting microstrip line with left-hand orthogonal slots (Left-Hand Orthogonal Slots) and the axial ratio is improved by optimizing slots size. The measured results show that 22.5% (VSWR<2) bandwidth and 16.2% 3 dB axial ratio bandwidth are achieved respectively and the gain is better than 9 dBi within 3 dB axial ratio bandwidth. The feed design of the antenna in the above structure is simple, and provides a reference for designing circularly polarized microstrip antenna.