径向双层介质加载圆波导的宽带TE_(11)-HE_(11)模式变换器

Broadband Circular Waveguide TE_(11)-HE_(11) Mode Converter Loaded with Radial Double-layer Dielectric

应用径向双层介质加载圆波导内可以产生混合模HE11模式的原理,提出一种径向双层介质加载圆波导的宽带TE11-HE11模式变换器。在X波段分析了该变换器内微波模式满足的麦克斯韦方程和边界条件,推导出HE11模式的特征方程及混合方程,最后将特征方程与混合方程联立,应用MATLAB软件进行数值求解得到物理模型的设计参数曲线。应用HFSS软件对设计的模式变换器进行模拟优化仿真,结果显示在8.4010.16GHz频带内输出HE11模式纯度大于96%,最大为99.59%,相对带宽可达18.7%,理论功率容量达3.3GW。该圆波导TE11-HE11模式变换器具有结构简单、输入输出共轴、转换效率高、转换频带宽、功率容量高等优点,应用于微波辐射系统可以极大地提高辐射系统的紧凑性。

Based on the fact that HE_(11) mode can be obtained at the exit when the specific microwave mode passes through a circular waveguide loaded with radial double-layer dielectric,a novel broadband circular waveguide TE_(11)-HE_(11) mode converter loaded with radial double-layer dielectric was proposed.Firstly,the Maxwell equations and boundary conditions of the microwave modes of the converter were analyzed,then the characteristic equation and the hybrid condition equation of HE_(11) mode were derived.Finally,the characteristic equation and the hybrid condition equation were solved simultaneously,and the designed parametric curve of the physical model was obtained by using MATLAB software.The commercial software High Frequency Structure Simulator(HFSS)was employed to simulate and optimize these parameters of the model.The results indicate that the purity of output hybrid mode HE_(11) of the converter exceeds 96% at 8.40 GHz to 10.16 GHz,and the highest is 99.59%,while the relative bandwidth is about 18.7%,and the power capability is as high as 3.3GW.The circular waveguide TE_(11)-HE_(11) mode converter has many advantages,such as the simple structure,coaxial input and output,high conversion efficiency,broad bandwidth and large power capability etc.,and when used in the field of microwave transmission,the proposed converter could significantly enhance the compactness of radiating system.