Circuit Design of a Compact 5-kV W-Band Extended Interaction Klystron

A low voltage (5 kV) ladder-type circuit is designed for the compact W-band extended interaction Klystron (EIK). Characteristics of the low voltage circuit are studied, synchronism relationship and electric field distribution are analyzed and optimized, and discussions on the circuit stability are embedded in the circuit design. In this paper, efficiency decline of the low voltage circuit is studied; two competing modes ( 2\pi cavity mode and upper \pi /8 mode) are observed, analyzed and suppressed. All of these efforts resulted in a low voltage W-band ladder-type EIK circuit with high stability and feasibility.