2.5GHz slot antenna array — Prototype applicator for heating applications

This paper describes a pragmatic approach for design, characterization and test of a low cost microstrip slot applicator with 140×140cm aperture, running at 2.5GHz, in the near field approximation. The applicator structure, designed on glass-reinforced epoxy copper clad (FR406), can handle 100-200W microwave power. The applicator is designed to heat lossy high dielectric liquids. A thermal map produced by the applicator on an absorbing material (Natrosol-water solution 0.4%w/v) is revealed using a low cost thermochromic crystal liquid sheet. The applicator is prepared to be equipped in the very near future with infrared (IR) thermopile array.