Propagation Characteristics of Periodic Azimuthally Corrugated Waveguides Derived by the FDTD Code COCHLEA

Azimuthal indentations have been proposed as an additional means to suppress the parasitic oscillations in the gyrotron stacked beam-tunnel. As a first step, a smooth waveguide with azimuthal indentations has been studied using COCHLEA code to identify their influence on the propagation characteristics. The - parameters have been calculated on the input and the output of the structure by decomposing the fields into several modes. It has been found that by increasing the indentations depth the field distributions change significantly and resonant effects are observed.