Electromagnetic Analysis of Reentrant Klystron Cavity

The mathematically simple formalism proposed earlier for calculating electromagnetic parameters of a reentrant cavity Barroso et al. (International Journal of Infrared and Millimeter Waves 26(8):1071–1083, 2005) is improved in usability by proposing a closed form solution for the parameter connecting two asymptotic regions of very small and very large gaps. The results obtained are verified with earlier reported results.