Design and simulation of Higher-Order Mode Coaxial Type Extended Interaction Cavities for a Ka-Band Multiple Beam Klystron

This article presents computer aided design and simulation results of intermediate and input/output cavities operating in 2π Mode for a 6-beam Ka band klystron. Coaxial type extended interaction cavities, in which the central conductor was optimized for symmetric field distribution, have been proposed for this multiple beam klystron (MBK). The coaxial cavity configuration with higher order mode allows usage of larger size cavities compared to conventional re-entrant fundamental TM mode cavities. Consequently, more beams can be accommodated and considerable ease in fabrication complexity can be achieved. The proposed MBK may find applications in high data rate mm-wave communication systems, satellite links, 5G wireless backhaul for which Ka band frequencies are becoming increasingly popular.