Papers by Keyword: Reflection Intensity

Abstract: An optically transparent microwave absorbing material based on the destructive interference theory was studied in this paper. The destructive interference phenomenon has been discussed and verified in the transparent microwave absorbing material. According to the destructive interference theory, we designed a type of three-layer microwave absorbing structure to enlarge the absorbing bandwidth. And its reflection coefficient curve stays below -10dB in the range of 7.5GHZ to 17.0GHz.

Abstract: Direct observations for high frequency microscopic dielectric distributions in cross sections of a multi-layer ceramic capacitor were carried out using non-contact type microwave probe. The measured data were imaged from the raw data and rounding data process. Using microwave reflection intensity mappings from cross sections of multi-layer ceramic capacitor, the dielectric permittivity distribution in micro-region of a multi-layer ceramic capacitor was measured at room temperature. The spatial resolution was experimentally estimated to be about 10 μm from mappings of the dielectric and inner electrode layers in a multi-layer ceramic capacitor.

Abstract: Microwave reflection intensity for microwave absorber, Cu-plate and Al2O3 (0001) single crystal substrate was measured from 8GHz to11GHz as a function of distance between single probe and sample at room temperature. The minimum reflection intensity was observed in the distance of 0.2mm between single probe and sample at 9.4GHz, although the reflection intensity was decreased with increasing distance in other measurement frequencies. The electromagnetic field analysis was hence carried out for simulation model that is defined with coaxial cable, probe and sample using finite differential time domain method. The reflection coefficient and impedance for simulation model were calculated, and compared to the experimental data. From results of electromagnetic analysis, the minimum point of reflection intensity was caused from an impedance matching.