Periodicity-suppressing effect of periodic lossy-dielectric-loaded cylindrical waveguide  

作　　者：杜朝海 刘濮鲲 薛谦忠 

机构地区：[1]Key Laboratory of High Power Microwave Sources and Technologies,Institute of Electronics,Chinese Academy of Sciences [2]Graduate University of the Chinese Academy of Sciences

出　　处：《Chinese Physics B》2010年第4期478-483,共6页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China (Grant Nos. 60871051,60871047 and 60971072)

摘　　要：Periodic dielectric-loaded waveguide is one of the diaphragmatic waveguides. For the excellent mode-selective propagation ability, it is of value for applications in gyrotron-traveling-wave amplifiers （gyro-TWT）, accelerators, and other microwave propagation systems. This paper focuses on studying the application of the strong lossy-dielectric- loaded periodic waveguide in millimeter-wave gyro-TWT. It is revealed that due to the lossy property of the dielectric, the energy in the dielectric slots is absorbed effectively and the high order Bloch harmonics induced by the periodicity of the structure are suppressed, which changes the discrete spectrum under losstess condition into a continuous one. As a result, the periodicity of the system is severely suppressed and a mode in the hollow region could be approximated by a fast wave mode in an empty waveguide. These results bring specific guidance for the applications of the lossy dielectric-loaded waveguide in gyro-TWTs and other devices.Periodic dielectric-loaded waveguide is one of the diaphragmatic waveguides. For the excellent mode-selective propagation ability, it is of value for applications in gyrotron-traveling-wave amplifiers （gyro-TWT）, accelerators, and other microwave propagation systems. This paper focuses on studying the application of the strong lossy-dielectric- loaded periodic waveguide in millimeter-wave gyro-TWT. It is revealed that due to the lossy property of the dielectric, the energy in the dielectric slots is absorbed effectively and the high order Bloch harmonics induced by the periodicity of the structure are suppressed, which changes the discrete spectrum under losstess condition into a continuous one. As a result, the periodicity of the system is severely suppressed and a mode in the hollow region could be approximated by a fast wave mode in an empty waveguide. These results bring specific guidance for the applications of the lossy dielectric-loaded waveguide in gyro-TWTs and other devices.

关 键 词：millimeter wave lossy dielectric Bloch harmonic gyrotron-traveling-wave amplifier 

分 类 号：TN814.7[电子电信—信息与通信工程] TN820.15