Abstract
A novel microwave high-resolution near-field imaging technique is proposed and experimentally evaluated in reflectometry imaging scenarios involving planar metal-dielectric structures. Two types of resonance near field probes-a small helix antenna and a loaded subwavelength slot aperture are studied in this paper. These probes enable very tight spatial field localization with the full width at half maximum around one tenth of a wavelength, λ, at λ/100-λ/10 standoff distance. Importantly, the proposed probes permit resonance electromagnetic coupling to dielectric or printed conductive patterns, which leads to the possibility of very high raw image resolution with imaged feature-to-background contrast greater than 10-dB amplitude and 50° phase. In addition, high-resolution characterization of target geometries based on the cross correlation image processing technique is proposed and assessed using experimental data. It is shown that printed elements features with subwavelength size ~λ/15 or smaller can be characterized with at least 10-dB resolution contrast.
Original language | English |
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Pages (from-to) | 189-200 |
Journal | IEEE Transactions on Instrumentation and Measurement |
Volume | 65 |
Issue number | 1 |
Early online date | 23 Sept 2015 |
DOIs | |
Publication status | Published (in print/issue) - Jan 2016 |
Keywords
- Probes
- Helical antennas
- Microwave imaging
- Dielectrics
- Microwave antennas
- Spatial resolution