Design And Research On The Output Circuit Of Broadband Klystron

Klystron is a kind of important microwave power amplifier. Klystron has been widely applied to radar systems, microwave communications, weather analysis, airwaves, microwave remote sensing, space technology and other science branches, because it has the following good performances: high output power, high efficiency, high gain, and better stabilization.With the advancement of microwave technology and the development of modern radar systems, it is hard to meet the needs by using narrowband klystron. The klystron is demanded for increasing output power and extending bandwidth.Based on two years effort, we have developed a C-band broadband multi-beam klystron with relative bandwidth of 11%. The MBK was obtained on the power level of 150 kW and the average power of 12 kW. In order to extend bandwidth effectively, the broadband output circuit of klystron has been designed with the extended-interaction technology, the multiple-beam technology, and the filter cavities have also been adopted to extend bandwidth. The design considerations, simulation, and test results are presented in this thesis.First, the computable model of cavities and output circuit are built by using a 3D modeling software, such as INVENTOR.Second, the simulation results of cavities and output circuit are obtained by using a 3D electromagnetism software, such as HFSS. The cavity parameters, including resonating frequency, field distribution, and R/Q are obtained also.Third, the parameters of klystron, including gain, bandwidth and power output are obtained by using compute program, such as AJDISK.Lastly, based on the design and simulation, a C-band broadband multi-beam klystron has been manufactured and tested. In order to validating the feasibility and veracity of design, we have compared the experiment results and the simulation results.