一种基于脊间隙波导的宽频带馈电线源设计

Design of a Broadband Feeding Linear Source Based on Ridge Gap Waveguide

设计了以脊间隙波导(RGW)功分网络为基本结构的宽频带馈电线源,该线源可用以激励平行板波导中的准TEM模式波,并用作宽带连续横向枝节(CTS)天线的馈电结构。首先对RGW阻带和单模带宽特性进行分析,以确定RGW的结构参数;进一步研究了宽带1分2功分器的设计方法、RGW模式到平行板波导模式的过渡结构方案;借助多级阻抗匹配和感性金属柱加载技术,实现了低反射等功率分配,以及输出端口到平行板波导的宽带匹配;最后将各分级结构级联得到1分8 RGW网络线源。对宽频带馈电线源进行了样机加工、装配和测试,在12 GHz~22 GHz频率范围内,其反射系数低于-15 dB,实测方向图与等幅同相均匀线源方向图吻合度很高,证明该馈电线源幅相一致性优异,是一种高效率的CTS天线馈电线源。

In this paper,a broadband feeding linear source with ridge gap waveguide(RGW)power divider network as the basic structure is designed to generate quasi-TEM wave in parallel-plate waveguide.The linear source will be used as the feeding structure of broadband continuous transverse stub(CTS)antenna.The structure parameters of RGW are determined based on the analysis of the stopband and single-mode bandwidth characteristics of RGW.Further research is conducted on the design method of broadband 1-to-2 power divider and the transition from RGW mode to parallel-plate waveguide mode.Equal power division with low reflection and broadband matching from the output port to parallel plate waveguide is implemented by means of multiple-section impedance matching and inductive metallic posts loading technique.The above structures are cascaded into a 1-to-8 RGW network linear source.Finally,the broadband linear source is fabricated,assembled,and measured.The measured results show that the reflection coefficient is less than-15 dB in the range of 12 GHz~22 GHz.The measured radiation patterns are well consistent with the radiation patterns of linear source with equal amplitude and phase,which prove that the consistency of amplitude and phase is excellent and the linear source is a high-efficiency feeding structure of CTS antenna.