Dielectric Field Concentrator of Microwave Radiation

Investigation is carried out to experimentally study concentration of microwave radiation with a wavelength ranging from 2.46 to 3.55 cm in a compact subwavelength region by a spherical resonator consisting of a dielectric sphere with a waveguide branch 1.15, 2, or 2.26 mm in diameter connected to the sphere tangentially to its surface or normally along its radius. The microwave radiation with a frequency ranging from 8.45 to 12.2 GHz excites Mie resonance oscillations in the spherical resonator with the attached waveguide branch. Frequency dependences of radiation from the waveguide branches show that the radiation intensity at the Mie resonance is almost two orders of magnitude higher than the intensity of the radiation exciting the resonant sphere.