The development of X-band and W-band sheet beam klystron in IECAS

Abstract

In this paper, the development of X-band and W-band sheet beam klystron (SBK) is introduced thoroughly in IECAS recently. The compact planar PCM and closed PCM system are used to focus the sheet beam for both of two types SBK. For the five multi-gap-cavity X-band SBK (XSBK), the cross section of beam is of 50mm4mm，and with the beam voltage of 150kV， beam current of 100A, the designed output power is about 4.6MW with the gain of 39.6dB and efficiency of 30.7%.The XSBK has been manufactured and tested successfully, and the output power is about 2.8MW with the beam voltage of 123kV and beam current of 70A. For the seven multi-gap-cavity Wband SBK (WSBK) with the beam cross section of 10mm0.5mm, the designed output power is about 30kW with the beam voltage of 75kV and beam current of 4A, the gain and efficiency is of 40dB and 10% respectively. At present, the WSBK has been manufactured, and the hot test is being processed. IntroductionCompared with the conventional cylindrical electron beam devices, the sheet beam klystron (SBK) has many advantages, such as low space charge, small focusing magnetic field, high efficiency, high output power and compact structures to meet the critical need for millimeter and sub-millimeter wave applications. The first high frequency output X band SBK has been tested in CPI in 2009 [1], and the first high power output W-band SBK was tested in NRL in 2013 [2]. Recently, many works have been carried out on the development of the sheet electron beam klystron for the XSBK and WSBK in IECAS [3]. The design and simulation of beam-wave interaction system, and the manufacture and test for these two types of SBK will be introduced in this paper.

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