High-power microwave tubes producing from several kilowatts up to many megawatts often generate modes which are not suitable for plasma heating, radar applications, or long distance transmission. To obtain a more desirable mode, a sequence of mode converters is often used with various high-power microwave sources such as gyrotrons and backward-wave oscillators. This thesis considers the theory, design, fabrication, and testing of smooth deformed-wall mode converters for this purpose.;Applying perturbation theory and Maxwell's equations, we can determine the coupling coefficients for various geometric deformations. A set of coupled-mode equations is employed to describe mode coupling due to the waveguide deformation.;The design, fabrication, and testing of a single-period 8.6 GHz TM;A design for a 110 GHz TE;TE... |