EQUIVALENT CIRCUIT ANALYSIS OF RIDGE-LOADED FOLDED-WAVEGUIDE SLOW-WAVE STRUCTURES FOR MILLIMETER-WAVE TRAVELING-WAVE TUBES

In this paper, a new simple equivalent circuit model for analysis of dispersion and interaction impedance characteristics of ridge-loaded folded-waveguide slow-wave structure is presented. In order to make the computational results more accurately, the effects of the presence of the beam-hole and discontinuity due to the waveguide bend and the narrow side dimension change of this kind of structure were considered. The dispersion characteristics and the interaction impedance are numerical calculated and discussed. The analytical results agree very well with those obtained by the 3-D electromagnetic high-frequency simulation software. It is indicated that the equivalent circuit methods are reliable and high efficiency.