Characteristic parameters in klystron output circuit by field analysis method

In order to solve the problem in calculating the klystron output circuit characteristic, based on field analysis and post-processing of 3D electromagnetic field simulation software ISFEL3D, a field analysis method is proposed. The theory analysis shows that the characteristic parameters, such as resonance frequency, real part of gap-impedance, external quality factor in all kinds of klystron output circuits including single-beam single-gap, multi-beam single-gap, single-beam multi-gap, multi-beam multi-gap klystron output circuit, can be calculated by the field analysis method. The calculated result of the single-beam single-gap klystron output circuit shows that the calculated result by field analysis method coincides with that by the reflectance phase method and that by the equivalent ga