Research on the stability of multi-gap extended cavity for W band Sheet beam EIK

A sheet-beam Extended Interaction Klystron (SBEIK) is an attractive MMW amplifier because of its high gain per unit length and compact configuration.[1–3] However, with a large width-high ratio sheet beam, it is easier to become instable in long transmission distance. In this paper, the stability of multi-gap extended cavity for W band Sheet beam EIK has been studied. The method for judging oscillation has been proposed. The electronic conductance of multi-gap extended cavity has been calculated. The result has been demonstrated by 3D-PIC software.