Cylindrical microwave heating applicator with only two modes

摘要

A microwave applicator including a generally cylindrical microwave containment chamber, a microwave energy source, and a feed structure connecting the microwave energy source to the containment chamber. The diameter of the containment chamber is designed according to a process that need only take into account supporting a microwave pattern having substantially only two transverse magnetic modes, each with a characteristic guide wavelength, where the guide wavelength of one mode is substantially equal to twice the guide wavelength of the other mode. Additionally, the interior diameter can be sized to minimize the index subscript numbers of the transverse magnetic modes. The feed structure of the applicator includes at least two feed apertures spaced physically apart around the cylindrical axis of the applicator by a physical angle equal to an electrical phase shift angle of the microwaves introduced through the respective apertures, which in a preferred embodiment is 90 degrees.