scholarly journals THE FREQUENCY CHARACTERISTICS OF COUPLED MICROSTRIP LINES / SUSIETŲJŲ MIKROJUOSTELINIŲ LINIJŲ DAŽNINĖS CHARAKTERISTIKOS

2013 ◽  
Vol 5 (2) ◽  
pp. 173-180
Author(s):  
Audrius Krukonis ◽  
Šarūnas Mikučionis
Keyword(s):  
Dielectric Constant ◽  
Transmission Lines ◽  
Characteristic Impedance ◽  
Frequency Characteristics ◽  
Effective Dielectric Constant ◽  
Matching Layer ◽  
Microstrip Lines ◽  
Signal Conductor ◽  
Voltage Current Characteristic ◽  
Difference Time

The article deals with the use of the finite difference time domain method and uniaxial perfectly matching layer for analysis of frequency characteristics of coupled microstrip transmission lines. It describes calculation techniques for voltage, current, characteristic impedance and effective dielectric constant of each signal conductor. Besides, it analyses the frequency dependencies of characteristic impedance and the effective dielectric constant. Article in Lithuanian. Santrauka Straipsnyje aptariamas baigtinių skirtumų laiko srities metodo taikymas ir absorbuojančio sluoksnio taikymas susietųjų mikrojuostelinių linijų analizei. Sudaryti ir išnagrinėti baigtinių skirtumų laiko srities metodu grįsti susietųjų mikrojuostelinių linijų matematiniai modeliai. Pateikiamos kiekvieno iš laidininkų įtampos, srovės, charakteringojo impedanso ir efektyviosios dielektrinės skvarbos skaičiavimo metodikos. Aptariami skaičiavimo metodikų pranašumai, trūkumai, pateikiamos jų tobulinimo kryptys.

scholarly journals Highly Sensitive Reflective-Mode Defect Detectors and Dielectric Constant Sensors Based on Open-Ended Stepped-Impedance Transmission Lines

Sensors ◽  
2020 ◽  
Vol 20 (21) ◽  
pp. 6236
Author(s):  
Pau Casacuberta ◽  
Jonathan Muñoz-Enano ◽  
Paris Vélez ◽  
Lijuan Su ◽  
Marta Gil ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Transmission Line ◽  
Transmission Lines ◽  
Characteristic Impedance ◽  
Reference Sample ◽  
Phase Variation ◽  
Dielectric Constants ◽  
High Impedance ◽  
Line Section ◽  
Highly Sensitive

In this paper, reflective-mode phase-variation sensors based on open-ended stepped-impedance transmission lines with optimized sensitivity for their use as defect detectors and dielectric constant sensors are reported. The sensitive part of the sensors consists of either a 90° high-impedance or a 180° low-impedance open-ended sensing line. To optimize the sensitivity, such a sensing line is cascaded to a 90° transmission line section with either low or high characteristic impedance, resulting in a stepped-impedance transmission line configuration. For validation purposes, two different sensors are designed and fabricated. One of the sensors is implemented by means of a 90° high impedance (85 Ω) open-ended sensing line cascaded to a 90° low impedance (15 Ω) transmission line section. The other sensor consists of a 180° 15-Ω open-ended sensing line cascaded to a 90° 85-Ω line. Sensitivity optimization for the measurement of dielectric constants in the vicinity of that corresponding to the Rogers RO4003C substrate (i.e., with dielectric constant 3.55) is carried out. The functionality as a defect detector is demonstrated by measuring the phase-variation in samples consisting of the uncoated Rogers RO4003C substrate (the reference sample) with arrays of holes of different densities.

Electrode effect on microwave properties of ferroelectric (BaxSr1-x)TiO3 thin films

2003 ◽  
Vol 784 ◽  
Author(s):  
Won-Jeong Kim ◽  
Sang-Su Kim ◽  
Tae-Kwon Song ◽  
Seung Eon Moon ◽  
Eun-Kyoung Kim ◽  
...  
Keyword(s):  
Thin Films ◽  
Dielectric Constant ◽  
Conformal Mapping ◽  
Transmission Lines ◽  
Dielectric Materials ◽  
Microwave Properties ◽  
Effective Dielectric Constant ◽  
Gap Size ◽  
High K ◽  
S Parameters

ABSTRACTMicrowave properties of coplanar waveguide (CPW) transmission lines fabricated on high dielectric materials, such as ferroelectric Ba1−xSrxTiO3 films, are highly sensitive on the dimension and shape of electrodes. A small change in device dimension affects the total electrical length of the CPW, which may mislead the effective dielectric constant of the dielectric layer. Furthermore, extracting dielectric constant of high-k thin films from the measured microwave properties, such as S-parameters, is very difficult. The well known a modified conformal mapping method frequently exhibits an inconsistent dielectric constant for CPW on high-k materials. CPW transmission lines were fabricated on high-k thin films, ferroelectric Ba0.6Sr0.4TiO3, which were deposited by the pulsed laser deposition with partial oxygen backgrounds. A large phase shift angle of 100° at 10 GHz was observed from the CPW (gap = 4 μm, length = 3 mm) with a 40 V of dc bias, which supports that the idea of the tunable microwave device application using ferroelectrics films. The dielectric constant of the thin ferroelectric film was extracted from the dimension of the CPW (gap, width, length) and the measured S-parameters by a modified conformal mapping. However, the dielectric constant of the ferroelectric thin film calculated by a modified conformal mapping exhibits a gap dependency; dielectric constant (990 ∼ 830) decreases with increasing gap size (4 ∼ 19 μm, respectively). For comparison, dielectric properties have been extracted by extensive EM-simulation using a HFSS™ (Ansoft) with observed dimensions of CPW devices. Total phase, which is closely related with the dielectric constant of the film, is strongly affected by gap size, film thickness, and slanted angle of CPW.

Enhancement of Electric Field inside Metallodielectric Metamaterial

2006 ◽  
Vol 11-12 ◽  
pp. 117-120
Author(s):  
Won Woo Cho ◽  
G. Zouganelis ◽  
Hitoshi Ohsato
Keyword(s):  
Dielectric Constant ◽  
Finite Difference ◽  
Electric Field ◽  
Time Domain ◽  
Finite Difference Time Domain ◽  
Near Field ◽  
Effective Dielectric Constant ◽  
Incident Electric Field ◽  
Metal Wires ◽  
Difference Time

A metallodielectric metamaterial have been investigated by using FDTD (Finite Difference Time Domain) method and fabricated with a resin based rapid prototyping machine. It was composed of 7 layers of parallel periodic copper wires embedded in resin. The metallodielectric metamaterial shows a different near field distribution with direction of incident electric field E that causes different electromagnetic (EM) properties. In particular, when incident electric field E is vertical to the wires inside resin, we observe enhacement of electric field in the vicinity of the embedded metal wires according to the incident direction of electirc field E as compared with dielectirc wihout metal wires. The enhanced electric field by the embedded metal wire is responsible for the enhancement of effective dielectric constant.

Sign in / Sign up

Export Citation Format

Share Document