A 10-kW Output Power Ka- to W-Band Klystron Harmonic Generator

The growing interest in high-power millimeter (mm)-wave amplifiers for various applications, such as high-resolution radar, active mm-wave imaging and atmospheric sensing, near object analysis, and 5G communications leading to novel solutions through which the researchers can overcome difficulty, complexity, and high expenses involved in fabrication technology of conventional vacuum electron devices including gyrotron, klystron, and traveling wave tube at
${W}$
-band frequency. Ka -band to
${W}$
-band klystron harmonics generator (KHG) can be an ideal solution to overcome these challenges. This article presents the design and simulation of a Ka -band to
${W}$
-band KHG, which triples input frequency and amplifies third harmonics. In the design of the beam–wave interaction region, two methods, including the Friedlander method and the core oscillation method, have been used. In the output cavity, TM130 higher mode was applied. Using high-order mode increases the dimensions of the output cavity and decreases mechanical complexity and cost. The results gained from simulation in particle-in-cell computer simulation technology (CST) solver showed that the output power could reach higher than 10.7 kW with 53-dB gain and 24% beam efficiency in TM310 output cavity mode. The electron beam voltage is 45 kV with a 1-A beam current.