Hybrid-mode analysis of circular waveguide with chiral dielectric lining for dispersion characteristics for potential application in broadbanding a gyro-traveling-wave tube

ABSTRACT

A circular waveguide with chiral dielectric lining was analyzed for hybrid mode dispersion relation. In chiral dielectric lining region, the different radial propagation constants, and in the central free-space region only one radial propagation constant for the left- and right- circularly polarized waves were considered. A method was presented to obtain the hybrid-mode dispersion relation of the proposed structure using the field matching technique. A numerical computer code was developed to solve the hybrid-mode dispersion relation and the solutions were plotted to explore the dispersion characteristics and shaping with the change of material and geometry parameters of the structure. Further, the azimuthal electric field intensity was plotted against radial coordinate to explore the position of field maxima for placing the gyrating electron beam for the potential application of the structure in a gyro-traveling-wave tube. Thus, out of the two modes studied, EH₀₁ and HE₀₁, the later found suitable for the operation of a gyro-traveling-wave tube.

KEYWORDS:

• Broadbanding technique
• dispersion shaping
• dielectric loaded circular waveguide
• gyro-TWT interaction structure
• wideband fast-wave structure

Additional information

Notes on contributors

Vishal Kesari

Vishal Kesari received M. Sc. (Physics) degree from Purvanchal University, India, and Ph. D. (Electronics Engineering) degree from Institute of Technology, Banaras Hindu University (IT-BHU) (now known as IIT-BHU), India, in 2001 and 2006, respectively. He has worked as Research Fellow at Centre of Advanced Study, Electronics Engineering Department, IT-BHU and significantly contributed to sponsored research projects at Centre of Research in Microwave Tubes, IT-BHU. He served as Lecturer at Birla Institute of Technology, Ranchi, India and Indian Institute of Information Technology, Allahabad, India before joining as Scientist at Microwave Tube Research and Development Centre, Defence Research and Development Organisation, Bengaluru, India. His research interest includes microwave and millimeter-wave vacuum electronic devices. He has authored two books:(i)Analysis of Disc-loaded Circular Waveguides for Wideband Gyro-TWTs (Lambert Academic Publishing AG & Co., Germany, 2009), and (ii) High Power Microwave Tubes: Basics and Trends (IOP Concise Physics; Morgan & Claypool Publishers, USA, 2018), and numerous research papers in peer-reviewed journals and conference proceedings. He has to his credit a number of international and departmental level awards. He has acted as reviewers for various peer-reviewed journals and conference proceedings. He is a fellow of Institution of Electronics and Telecommunication Engineers (IETE), India and a life member of Vacuum Electronic Devices and Application Society (VEDAS), India.

J. P. Keshari

Jaishanker Prasad Keshari received B. Tech. (Electronics and Communication Engineering) degree from Uttar Pradesh Technical University, Lucknow, India, M. Tech. (Instrumentation and Control Engineering) degree from Sant Longowal Institute of Engineering and Technology, Longowal, India, and Ph. D. (Electronics and Communication Engineering) degree from Sharda University, Greater Noida, India in 2004, 2007 and 2017, respectively. He was an Assistant Professor at Noida Institute of Engineering and Technology College, Greater Noida, India, and at Galgotia College of Engineering and Technology, Greater Noida, India. Currently, he is an Associate Professor at ABES Engineering College, Ghaziabad, India. His research interest includes microstrip patch antenna and waveguide structures for gyro-traveling-wave tubes. He has a number of research papers in peer-reviewed journals and conference proceedings. He has received a best teacher award at Noida Institute of Engineering and Technology, Noida, India and Galgotia College of Engineering and Technology, Greater Noida, India. He has acted as a reviewer for various peer-reviewed journals and conference proceedings. He is a Fellow of Institution of Electronics and Telecommunication Engineers (IETE), India.