volume | PIER Journals

Abstract

A high-efficiency interaction circuit for Ka-band klystron has been proposed based on a novel internal coupling cavity. Driven by a 25 kV, 5 A pencil beam, the interaction circuit can produce a peak output power of 38.4 kW at Ka-band, and the electronic efficiency is 30.7%. The electromagnetic properties of the unequal slot multi-gap cavity and internal coupling cavity have been studied and compared. The internal coupling cavity demonstrated a higher coupling coefficient and characteristic impedance than the unequal slot multi-gap cavity, which can improve the circuit efficiency. Stability and pattern analysis have been performed on the output cavity. A four-gap output cavity has been designed. Simulation results show that there is no mode competition and oscillation in the output cavity. The corresponding beam optics has also been designed to produce the required beam. Compared with the existing work, the interaction circuit can produce almost twice the output power with the same beam voltage and Brillouin focusing magnetic field. The efficiency is also improved by 6 percent.

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Dr. Bingchuan Xie

Dr. Rui Zhang

Dr. Yong Wang

Dr. Xu Zhang

Dr. Xiudong Yang

Dr. Yunfeng Liao

Dr. Zhihui Geng