A model of the slowwave cavity structures that can be used for the analysis of electrodynamic parameters and excitation by the fixed current is electrodynamically substantiated. A possibility of the calcu lation of electrodynamic parameters using the 3D simulation is demonstrated for the slowwave cavity struc tures. The calculated electrodynamic parameters of the two and fourport slowwave structures are pre sented.
The properties of the local coupling impedance that determines the efficiency of the electron–wave interaction in periodic slow-wave structures are investigated. This impedance is determined (i) through the characteristics of the electromagnetic field in a slow-wave structure and (ii) through the parameters of a two-port chain simulating the structure. The continuous behavior of the local coupling impedance in the passbands of slow-wave structures, at the boundaries of the passbands, and beyond the passbands is confirmed with the help of a waveguide–resonator model.