Analysis of the transient response in periodic structures based on a coupled-resonator model

The transient response of periodic structures is analyzed numerically by a coupled-resonator model. The traveling and the standing waves are approximated by superposition of the cell-mode (eigenmode in an isolated boundary) in each cell. The wave propagation is modeled by the signal transmission along the equivalent-circuit chain through the mutual inductance. A computer simulation code was developed to solve the time-dependent circuit equations using the difference equation. The code was used to study the transient beam-loading in a disk-loaded accelerating structure, and its compensation method was tested. This method has also been used to analyze the rf-pulse compressor as well as the traveling-wave output-circuit in a high-power klystron inside a particle-in-cell klystron simulator. This lecture describes the basic concept of the coupled-resonator model, application to the disk-loaded structure, and some details of the numerical method. (author)