A Coaxial Microwave Heating Applicator with Double Loading Discs for a Confined Power Loss Density Pattern

A microwave heating applicator with a confined heating pattern is presented in this paper. Compared to conventional coaxial applicators, the proposed design is immune to influences of surrounding boundaries. This feature is provided by double capacitive loading discs at the beginning and the end of the applicator's tip. Hot spots with high power loss density are formed by such loading elements where strong electric fields are presented. In addition, the proposed applicator can also be used as a sensor with a high sensitivity by measuring the return loss over the frequency at the feed port while the applicator is immersed into the liquid under test.