Patent ID: 7208710

Claim:
A method for uniform microwave heating of a microwave absorptive target comprising: sizing a microwave housing having a longitudinal axis to propagate a selected waveguide mode at an operating frequency; locating the microwave absorptive target in an axial cross-sectional area of the microwave housing relative to the longitudinal axis; and applying microwave energy at the operating frequency into the microwave housing to propagate a circularly polarized waveguide mode in the microwave housing to time average azimuthal field strength across the axial cross-sectional area, by: splitting the applied microwave energy into a first signal and a second signal in phase with the first signal; and applying the first signal and the second signal into the microwave housing: ninety angular degrees apart azimuthally relative to the longitudinal axis to provide the first signal and the second signal into the microwave cavity as respective orthogonal components of an applied field strength, and separated apart longitudinally an operating frequency quarter wavelength.