scholarly journals Planar Sensor for Material Characterization Based on the Sierpinski Fractal Curve

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
P. H. B. Cavalcanti Filho ◽  
J. A. I. Araujo ◽  
M. R. T. Oliveira ◽  
M. T. de Melo ◽  
M. S. Coutinho ◽  
...  

This paper presents a planar and compact microwave resonator sensor to characterize materials. The geometry of the resonator is based on the Sierpinski fractal curve and has four poles in the frequency range from 0.5 GHz to 5.5 GHz. Any of the four poles can be used to measure samples with low permittivity values, where the first pole is suitable for samples with high permittivity values. The sensitivity of the poles and return losses of the sensor are presented and obtained using a full-wave 3D simulator software. The device is manufactured and validated through a comparison between simulated and measured results.

1995 ◽  
Vol 381 ◽  
Author(s):  
Ken Numata ◽  
Thomas R. Seha ◽  
Shin-Puu Jeng ◽  
Tsuyoshi Tanaka

AbstractMethyl siloxane spin-on-glass (SOG) is a conventional gap-filling material. In accordance with the requirement of low permittivity, many of major SOG suppliers are developing new types of methyl siloxane SOGs.The most interesting property of these SOGs is their permittivity, which we measured by making stack structures of Al-0.5%Cu / TEOS CVD SiO2 / SOG / n+ Si. We also studied I-V characteristics, refractive indices, FT-IR spectra, stress, and moisture resistance.All of the SOGs showed small stress and fair moisture resistance. Leakage currents were less than 2.5E-10 A/cm2 for bias voltages up to 5V. Permittivities ranged from 2.9 to 3.6. We observed a correlation between permittivity and FT-IR spectral features associated with Si-O-Si bonds. Reducing the number density of Si-O-Si bonds may be an effective way to lower the permittivity of this class of SOGs


2010 ◽  
Vol 25 (9) ◽  
pp. 1803-1811 ◽  
Author(s):  
Haibo Yang ◽  
Hong Wang ◽  
Li Shui ◽  
Li He

Ni0.8Zn0.2Fe2O4/Ba0.6Sr0.4TiO3 (NZO/BST) composites with high permittivity and low loss were synthesized via the hybrid processing route. The composites possess very dense and homogenous microstructure. The NZO/BST composites show good dielectric properties and magnetic properties with low loss in high frequency range. This indicates that this kind of magnetodielectric composites can be used in high-frequency communications for the capacitor-inductor integrating devices such as electromagnetic interference filters and antennas. The permittivities of the composites were also fitted using the combination of Maxwell–Wagner polarization and modified Curie–Weiss law.


2014 ◽  
Vol 6 (6) ◽  
pp. 611-618 ◽  
Author(s):  
Yung-Wei Chen ◽  
Hung-Wei Wu ◽  
Yan-Kuin Su

In this paper, a new multi-layered triple-passband bandpass filter using embedded and stub-loaded stepped impedance resonators (SIRs) is proposed. The filter is designed to have triple-passband at 1.8, 2.4, and 3.5 GHz. The 1st and 2nd passbands (1.8/2.4 GHz) are simultaneously generated by controlling the impedance and length ratios of the embedded SIRs (on top layer). The 3rd passband (3.5 GHz) is generated by using the stub-loaded SIR (on bottom layer). Using the embedded SIR, the even modes can be tuned within very wide frequency range and without affecting the odd modes. Therefore, the design of multi-band filters with very close passbands can be easily achieved and having a high isolation between the passbands. The filter can provide the multi-path propagation to enhance the frequency response and achieving the compact circuit size. The measured results are in good agreement with the full-wave electromagnetic simulation results.


Radio Science ◽  
2009 ◽  
Vol 44 (3) ◽  
pp. n/a-n/a ◽  
Author(s):  
Milo W. Hyde ◽  
James W. Stewart ◽  
Michael J. Havrilla ◽  
William P. Baker ◽  
Edward J. Rothwell ◽  
...  

Author(s):  
H.-J. Cheng ◽  
J.F. Whitaker ◽  
K.J. Herrick ◽  
N. Dib ◽  
L.P.B. Katehi ◽  
...  

2009 ◽  
Vol 3 (3) ◽  
pp. 145-155 ◽  
Author(s):  
Jan Petzelt

Results achieved using the infrared/THz spectroscopy of various inhomogeneous dielectrics in the Department of Dielectrics, Institute of Physics, Prague, during the last decade are briefly reviewed. The discussion concerns high-permittivity ceramics with inevitable low-permittivity dead layers along the grain boundaries, relaxor ferroelectrics with highly anisotropic polar nano-regions, classical matrix-type composites, core-shell composites, filled nanoporous glasses, polycrystalline and epitaxial thin films, heterostructures and superlattices on dielectric substrates. The analysis using models based on the effective medium approach is discussed. The importance of depolarizing field and of the percolation of components on the effective ac dielectric response and the excitations contributing to it are emphasized. .


Author(s):  
Andrey V. Mozharovskiy ◽  
Oleg V. Soykin ◽  
Aleksey A. Artemenko ◽  
Roman O. Maslennikov ◽  
Irina B. Vendik

Introduction. Increased data rate in modern communication systems can be achieved by raising the operational frequency to millimeter wave range where wide transmission bands are available. In millimeter wave communication systems, the passive components of the antenna feeding system, which are based on hollow metal waveguides, and active elements of the radiofrequency circuit, which have an interface constructed on planar printed circuit boards (PCB) are interconnected using waveguide-to-microstrip transition.Aim. To design and investigate a high-performance wideband and low loss waveguide-to-microstrip transition dedicated to the 60 GHz frequency range applications that can provide effective transmission of signals between the active components of the radiofrequency circuit and the passive components of the antenna feeding systemMaterials and methods. Full-wave electromagnetic simulations in the CST Microwave Studio software were used to estimate the impact of the substrate material and metal foil on the characteristics of printed structures and to calculate the waveguide-to-microstrip transition characteristics. The results were confirmed via experimental investigation of fabricated wideband transition samples using a vector network analyzer Results. The probe-type transition consist of a PCB fixed between a standard WR-15 waveguide and a back-short with a simple structure and the same cross-section. The proposed transition also includes two through-holes on the PCB in the center of the transition area on either side of the probe. A significant part of the lossy PCB dielectric is removed from that area, thus providing wideband and low-loss performance of the transition without any additional matching elements. The design of the transition was adapted for implementation on the PCBs made of two popular dielectric materials RO4350B and RT/Duroid 5880. The results of full-wave simulation and experimental investigation of the designed waveguide to microstrip transition are presented. The transmission bandwidth for reflection coefficient S11 < –10 dB is in excess of 50…70 GHz. The measured insertion loss for a single transition is 0.4 and 0.7 dB relatively for transitions based on RO4350B and RT/Duroid 5880.Conclusion. The proposed method of insertion loss reduction in the waveguide-to-microstrip transition provides effective operation due to reduction of the dielectric substrate portion in the transition region for various high-frequency PCB materials. The designed waveguide-to -microstrip transition can be considered as an effective solution for interconnection between the waveguide and microstrip elements of the various millimeter-wave devices dedicated for the 60 GHz frequency range applications.


Sign in / Sign up

Export Citation Format

Share Document