Design and Experiment of a Super-wide Band Output Circuit with Two Channels for Klystron Applications

The design ideas and performance process of a super-wide band and two channels output circuit on a klystron are presented. A super-wide band two-channel double-gap coupled-cavity output circuit, whose bandwidth is over 550 MHz, is designed at S band by Ansoft HFSS. A channel switch structure is designed, and the resonance parameters of the two channels are determined. Then, a conclusion is made that channels can be switched easily through tuning the coupled-slot without changing the parameters of the two cavities. The frequencies of each mode in the double-gap coupled-cavity output circuit are simulated through calculating the model by Ansoft HFSS. The frequencies of each mode accord with the cold test mainly. The gap impedance of double-gap coupled-cavity, which is simulated by analysis of equivalent lumped element circuit, also accords with the cold test very well.