Ka 頻段與 W 頻段調速管之模擬

Abstract

本文研究微波在 Ka 頻段中,分佈作用調速管 (Extended Interaction Klystron, 簡稱 EIK) 作用段之模擬與設計。傳統調速管雖然擁有高輸出 功率的特性,但是在高頻作用段的電子效率較低、頻寬也較窄,提高 效率與頻寬即是重要的研究項目之一。以分佈作用腔取代後,因高特 徵阻抗 R/Q 的特性,以電腦數值模擬來計算後,預期 Ka 頻段調速管會 有頻寬 359 MHz、最大增益 27 dB 和最大電子轉換效率 19%。另一方 面,同時協助國家中山科學研究院進行 W 頻段的研究,使 W 頻段調速 管達到頻寬 637 MHz、最大增益 34 dB 和最大電子轉換效率 18%。在 數值計算上,除了使用現有的商用軟體以外,也以蒙地卡羅方法進行 模擬,能夠有效減少電腦運算時間與人力。

This study focus on the design and simulation of extended interaction klystrons (EIK) for Ka-band microwave. Traditional klystrons have high out- put power at high frequencies, but the efficiency and bandwidth are relatively small. Improving the efficiency and the bandwidth are the important research works. By applying the EIK, the efficiency, gain, and bandwidth increase, since it has a higher characteristic impedance R/Q. In addition, we also as- sisted Chungshan Institute of Science and Technology (CSIST) in the design of W-band EIK. The design is based on the computer modeling, in which we adapted the small and large signal simulation code by Monte Carlo method. This method can reduce the simulation time and human labor. We expect that the Ka-band EIK would have 359 MHz of bandwidth and maximum gain of 27 dB, and maximum efficiency of 19%, and that W-band EIK would have have 637 MHz of bandwidth and maximum gain of 34 dB, and maximum ef- ficiency of 18%.