Ka-band E-plane The Circulator Modeling, Structural Design And Broadband Technology

The waveguide circulator is applied to signal transmission devices of radar antenna-feed unit for signal channel conversion, which minimizes the size of system and afford protection. They are also widely applied for civil and military applications.The waveguide circulator mainly includes two structure : junction and differential phase shifter. The junction circulator comprise H-plane and E-plane design scheme. E-plane waveguide junction circulator can endure more high power and be easy to minimize the dimension of system, compared with H-plane structure. But, the bandwidth of E-plane circulator is lower than 5 percent, which is the usage limitation. The E-plane circulator have very important research and developing value, which works in millimeter wave band. The thesis take them as the research object and find their design method of broadening the band-width by simulation and structure design for mass production, that is widely used to civil and military applications. Three expanded aspects are following.1,Based on circulator transmission theory, analysis of working principle and find the key factor which affects the performance. The design consideration are confirmed based on E-plane circulator/isolator transmission structure, field distribution, ferrite sample, and invariable magnet material.2,The E-plane circulator/isolator simulation model is built with Ansoft HFSS microwave analysis software based on design project. The best simulation model is selected by compared with different design structure and simulation results. It is optimized for right parameters.3,The final device dimension is confirmed by HFSS simulation model. Mechanic structure is designed by Solidworks software. The best structure design is selected by compared with different design scheme, based on the principles of mechanic intensity, stable electric performance and easy fabrication. Establish the arts and crafts flow and analysis of structure reliability and temperature stability, find the design bugs and solutions. Finally, the device is fabricated and tuned.The measured results show that specification of experimental device totally satisfy the research goal demands.