Sinkevych O. Near-field microwave introscopy of dielectric samples in view of spatial distribution of the probe's field.

The thesis is devoted to theoretical and experimental investigation of the scanning near-field microwave microscopy of the complex objects with low loss tangent and corresponding inverse problems solutions. An algorithm for a wide spectrum of inverse problems solution in microwave microscopy and introscopy was developed. It allowed us to reconstruct fiberwise images of the test sample with volumetric inhomogeneites. A novel type of microwave microscope (with an active probe) was developed. Two implementations of this microscope type were created: based on broadband microwave microscopes were also constructed: based on the ?/4 resonator and on the ring resonator. A high steepness range of quasiperiodic regime of interaction with external signal source was used for active probe sensitivity increasing. A broadband microscope based on the linear multimode coaxial resonator was also build. Modification of modulation auto-tuning scheme based on controlled resonator and microwave generator of fixed frequency was proposed. An aperture microprobe was applied for the first time for volumetric inhomogeneites scanning. This approach increases signal informativity and allows performing express estimation of defects parameters. A novel method for increasing spatial resolution of subsurface defects visualization in near-field microwave microscopy was proposed.