Analysis of cylindrical waveguide with corrugation and synthesis of radiated beams pattern

The dielectric waveguide with corrugation has been of considerable interest in the optical or millimeter wave regions, because of its applications such as filters, couplers and leaky wave antennas. In the frequency region where the spatial harmonics become leaky, the wave energy is leaked in several different directions. Conventional corrugations consist of a fundamental and harmonic wave forms with respect to a period. The leakage directions from the waveguides are determined almost by the fundamental period of the corrugation form, and it is not so easy to control the leakage intensity in each direction at will. We analyze the leaky wave characteristics of cylindrical waveguides with the corrugation of sinusoidal wave forms whose period ratios are nonintegral. The radiation pattern of a fabricated waveguide with corrugation agrees well with the calculated value.