Dissertations / Theses on the topic 'Microstrip resonator'
To see the other types of publications on this topic, follow the link: Microstrip resonator.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Microstrip resonator.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Reppel, Michael. "Novel HTS microstrip resonator configurations for microwave bandpass filters." [S.l. : s.n.], 2000. http://deposit.ddb.de/cgi-bin/dokserv?idn=960169245.
Full text
2
Wimberley, Jack Timpson. "Behavior of Periodic Coupled Microstrip Resonators." Thesis, Boston College, 2011. http://hdl.handle.net/2345/1983.
Full textAbstract:
Thesis advisor: Krzysztof KempaThe resonant modes of a sequence of periodically spaced microstrip resonators is studied. The system is analyzed as transmission line with periodic capacitive gaps, as a waveguide with apertures via normal mode expansion, and through a derivation of the static fields in the gap between two microstrip resonators via conformal mapping. FDTD simulations are also performed to numerically calculate the resonant modes of the sequence and also its absorption spectrum when it contains a lossy dielectric. It is found, as expected, that when the gap size is large, the microstrip resonators are uncoupled and there resonant modes are unperturbed. As the gap size narrows, the resonators become strongly coupled, and changing boundary conditions perturb the resonant modes upwards in frequency. Moreover, an additional resonant mode is observed that does not correspond to any uncoupled mode
Thesis (BS) — Boston College, 2011
Submitted to: Boston College. College of Arts and Sciences
Discipline: College Honors Program
Discipline: Physics Honors Program
Discipline: Physics
3
Crouch, David Andrew. "Gallium arsenide field effect transistors microstrip integrated circuit dielectric resonator oscillators." Master's thesis, University of Cape Town, 1988. http://hdl.handle.net/11427/8329.
Full textAbstract:
Bibliography: leaves 175-177.This thesis is concerned with Gallium Arsenide Metal Semiconductor Field Effect Transistor Microstrip Integrated Circuit Dielectric Resonator Oscillators (GaAs MESFET MIC DROs) - the different types, their design and their performance compared to other high Q factor (ie narrowband) microwave oscillators. The thesis has three major objectives. The first is to collate the information required to build microwave DROs. The second is to present the practical results obtained from Dielectric Resonator Bandreject and Bandpass filters (DR BRFs and DR BPFs). The last is to present and compare results from a DR stabilised microstrip oscillator and three types of series feedback DROs. Narrowband oscillators are usually evaluated in terms of their frequency stability, reliability, size, cost, efficiency and output power characteristics. In terms of these parameters DROs outperform Gunn cavity oscillators and are only bettered by crystal locked sources in terms of frequency temperature stability and long-term stability. The components of a GaAs MESFET MIC DRO possess ideal properties for the construction of a narrowband source with the exception of the long term stability of the GaAs MESFET. GaAs MESFET•DROs have the best published DRO results for efficiency, output power, power temperature stability and external Q factor. Basic oscillator theory derived by Kurokawa can be applied to both negative resistance and feedback oscillators. Impedance locus, device-line and operating point concepts provide a convenient framework for understanding hysteresis in microwave oscillators. The work by Kurokawa can also be translated into the S-parameter domain which has proved convenient for the design of microwave oscillators.
4
Virdee, Balbir Singh. "The design and realisation of electronically tunable dielectric resonator microstrip filters." Thesis, London Metropolitan University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307112.
Full textAbstract:
Many of todays' sophisticated communication systems, particularly those operating in the microwave frequency range, have a growing demand for highly selective and frequency agile filters with fast tuning rates. At microwave frequencies above 2GHz, filters that combine both tuning speed and high selectivity are difficult to realise. Unloaded Q values in the range of 1000 are required for reasonable selectivity. At present, these requirements with the exception of tuning speed are mainly fulfilled by electronically tuned filters employing yttrium iron garnet (YIG) resonators. An alternative solution to this problem is to utilise high-Q dielectric resonators (DRs) in-conjunction with an appropriate tuning mechanism to realise tunable filters. DRs can provide unloaded Q-factors comparable to waveguide resonators (typically 10,000 @ 10GHz), but at a substantially lower weight and smaller volume. DRs are also compatible with a microstrip environment which eliminates the need for microstrip to waveguide adaptors. This thesis is devoted to the study of the design and realisation of electronically tuned microwave filters employing dielectric resonators. Knowledge of the values of the coupling coefficient between a pair of DRs is essential for the design of both the bandpass and bandstop filters using these resonators. This necessitates the use of an accurate expression for the coupling coefficient which was derived by performing an electromagnetic analysis on the DR structure. This analysis also took into account the effects of the actual circuit environment such as the resonator support spacer and the dimensions of the enclosure. The experimental data presented shows very good agreement with the computed data. Novel techniques for the tuning of the DR operating in its fundamental mode are presented. These tuning configurations incorporating GaAs varactor diodes have been investigated to determine a circuit which greatly perturbs the DR fundamental mode. The amount of tuning that can be obtained by these methods exceeds more than 60MHz of the unperturbed value of resonant frequency with acceptable amount of Q-factor degradation. These tuning characteristics are superior to similar devices reported to date. A simple analytical expression is also derived for determining the tuning range of such a structure. Techniques for the design of novel electronically tunable DR bandpass and bandstop filters having either a Chebyshev or Butterworth response are presented. Design for prescribed response, starting from a low-pass lumped-element prototype filter is outlined. The bandpass filter structure consists of cascaded resonators, with the end resonators coupled to microstrip arcs on a substrate, whereas, the bandstop filter consists of a microstrip line with resonators mounted at intervals of one-quarter-wavelength. Tuning is achieved by varying a bias voltage to the varactor. The measured performances of several practical devices operating in the S-band are presented, these agree closely with theory. The centre frequency of these filters is within 2.46% and the bandwidth is within 3.75% of the desired values.
5
Zhao, Bo. "Composite Right/Left-Handed (CRLH) Microstrip Resonant Antennas." University of Cincinnati / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1123784412.
Full text
6
Hosking, Michael William. "Microstrip ring resonator at microwave frequencies : applications to superconducting and normal circuits." Thesis, University of Portsmouth, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336916.
Full text
7
Adusumilli, Pallavi. "Effects of Mutual Coupling on Zeroth Order Resonator (ZOR) Antennas." University of Cincinnati / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1459439568.
Full text
8
Kemppinen, E. (Esa). "Determination of the permittivity of some dielectrics in the microwave and millimetre wave region." Doctoral thesis, University of Oulu, 1999. http://urn.fi/urn:isbn:9514251954.
Full textAbstract:
Abstract
In the first part of this study, determination of the dielectric properties of the low loss microwave ceramic material, barium nonatitanate (Ba2Ti9O20), around 1 GHz is discussed. The structures under test were coaxial resonators, the cores of which were made of barium nonatitanate and the metallization was realised by thick film silver. The measured value of the real part of the relative dielectric constant was εr = 37 and that of the loss tangent was tan σ = 0.00014. The change of the resonance frequency of the coaxial resonators with temperature, in the range -20 … +80 C, was 4 ppm/ C. In addition, realisation of compact interdigital and comb-line bandpass filters was demonstrated for the 900 MHz mobile phone band. Besides Ba2Ti9O20, Ba(Sm,Nd)2Ti5O14 ceramic material with a dielectric constant of εr = 78 was also employed in order to improve the miniaturisation. The volume of the smallest filter was 2 cm3 and the weight was 9 g.
In the second part of this study, various measurement methods have been demonstrated to determine the real part of the relative permittivity of FR4 fibreglass circuit board. Test structures were straight asymmetric open-circuited strip lines. It was found that the real part of the relative permittivity decreased slightly with frequency. At 0.72 GHz and 4.5 GHz, εr values of 4.3 and 4.1, respectively, were measured. All the characterisation methods used gave consistent values for εr, and electromagnetic simulators were used to verify the results.
In the third part of this study, the structures under test were microstrip or strip line transmission lines, the S parameters of which were measured by using on-wafer measurement techniques. It was found that the insertion loss of the 10 mm long etched Cu microstrip was slightly less than that of the Ag microstrips which were manufactured by etching and gravure offset printing techniques, respectively. The performance of the Ag microstrips was, however, similar. In addition, a theoretical basis was established for the determination of εr of the dielectric substrate and the attenuation coefficient of the transmission lines under test. The calculations were based on signal flow diagrams. The method was applied to determine the dielectric and loss properties of a commercial, Kyocera, Japan, LTCC (Low Temperature Cofired Ceramic) material up to 50 GHz. The measured value of the real part of the relative permittivity was εr = 5.7, and the loss tangent was approximately tan σ = 0.003.
The essential idea behind the studies reported in this thesis was twofold. First, the studies aimed at characterising dielectric media which find usage in the realisation of UHF, microwave or millimetre wave circuits. Second, the studies aimed to obtain data of immediate value in practical design work. For this reason, the structures under test were transmission lines having extensive usage in practical high frequency circuit design.
9
Morsy, Mohamed Mostafa. "DESIGN AND IMPLEMENTATION OF MICROSTRIP MONOPOLE AND DIELECTRIC RESONATOR ANTENNAS FOR ULTRA WIDEBAND APPLICATIONS." OpenSIUC, 2010. https://opensiuc.lib.siu.edu/dissertations/169.
Full textAbstract:
Ultra wide-band (UWB) technology is considered one of the very promising wireless technologies in the new millennium. This increases the demand on designing UWB antennas that meet the requirements of different UWB systems. In this dissertation, different UWB antennas are proposed such as an antenna that covers almost the entire UWB bandwidth, 3.5-11 GHz, as defined by the federal communication commission (FCC). This antenna has a size of 50×40×1.5mm3. Miniaturized worldwide UWB antennas are also introduced. Miniaturized worldwide UWB antennas that have compact sizes of (30×20×1.5) mm3, and (15×15×1.5) mm3 are also investigated. The designed worldwide UWB antennas cover the UWB spectrums defined by the electronic communication committee (ECC), 6-8.5 GHz, and the common worldwide UWB spectrum, 7.4-9 GHz. A system consisting of two identical antennas (transmitter and receiver) is built in the Antennas and Propagation Lab at Southern Illinois University Carbondale (SIUC) to test the coupling properties between every two identical antennas. The performance of that system is analyzed under different ii conditions to guarantee that the transmitted signal will be correctly recovered at the receiver end. The designed UWB antennas can be used in many short range applications such as wireless USB. Wireless USB is used in PCs, printers, scanners, laptops, MP3 players, hard disks and flash drives. A new technique is introduced to widen the impedance bandwidth of dielectric resonator antennas (DRAs). DRA features compactness, low losses, and wideband antennas. Different compact UWB DRAs are investigated in this dissertation. The designed DRAs cover a wide range of frequency bands such as, 6.17-24GHz, 4.23-13.51GHz, and 4.5-13.6GHz. The designed DRAs have compact sizes of 1×1×1.5cm3, 0.9×0.9×1.32cm3, 0.6×0.6×1cm3, and 0.6×0.6×0.9cm3; and cover the following frequency bands 4.22-13.51GHz, 4.5-13.6GHz, 6.1-23.75GHz, and 6.68-26.7GHz; respectively. The proposed DRAs may be used for applications in the X, Ku and K bands such as military radars and unmanned airborne vehicles (UAV).
10
Scher, Aaron David. "Microstrip post production tuning bar error and compact resonators using negative refractive index metamaterials." Texas A&M University, 2005. http://hdl.handle.net/1969.1/2337.
Full textAbstract:
In this thesis, two separate research topics are undertaken both in the general area
of compact RF/microwave circuit design. The first topic involves characterizing the
parasitic effects and error due to unused post-production tuning bars. Such tuning bars
are used in microwave circuit designs to allow the impedance or length of a microstrip
line to be adjusted after fabrication. In general, the tuning bars are simply patterns of
small, isolated sections of conductor adjacent to the thru line. Changing the impedance
or length of the thru line involves bonding the appropriate tuning bars to the line.
Unneeded tuning bars are simply not removed and left isolated. Ideally, there should be
no coupling between these unused tuning bars and the thru line. Therefore, the unused
tuning bars should have a negligible effect on the circuit??s overall performance. To
nullify the parasitic effects of the tuning bars, conventional wisdom suggests placing the
bars 1.0 to 1.5 substrate heights away from the main line. While successful in the past,
this practice may not result in the most efficient and cost-effective placement of tuning
bars in today??s compact microwave circuits. This thesis facilitates the design of compact
tuning bar configurations with minimum parasitic effects by analyzing the error
attributable to various common tuning bar configurations with a range of parameters and
offset distances. The error is primarily determined through electromagnetic simulations,
and the accuracy of these simulations is verified by experimental results. The second
topic in this thesis involves the design of compact microwave resonators using the
transmission line approach to create negative refractive index metamaterials. A survey
of the major developments and fundamental concepts related to negative refractive index
technology (with focus on the transmission line approach) is given. Following is the
design and measurement of the compact resonators. The resonators are also compared to
their conventional counterparts to demonstrate both compactness and harmonic
suppression.
11
Shi, Ruirong. "Zeroth-Order Resonator (ZOR) Antenna Using Composite Right/Left-Handed (CRLH ) Microstrip Transmission Line (TL)." University of Cincinnati / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1301714086.
Full text
12
Farooqui, Muhammad Fahad. "Compact circularly polarized slot-ring antenna and microstrip bandpass filter using triangular open-loop resonators." Texas A&M University, 2006. http://hdl.handle.net/1969.1/4969.
Full textAbstract:
In this thesis two different research topics are undertaken, both in the area of compact
RF/microwave circuits design. The first topic involves the design of a compact circularly
polarized (CP) slot-ring antenna. A study of several compact CP microstrip and slotline
antennas reported in the past has been carried out. In this research, a method of reducing
the size of a printed slot-ring antenna is proposed. The reduction in size is achieved by
introducing meandered-slot sections in the ring. Circular polarization is achieved by
introducing an asymmetry, also a meandered-slot section, and feeding the antenna at an
angle of 45o from the asymmetry using a microstrip feed line. The minimum axial ratio
of 0.4 dB is obtained at 2.46 GHz, which is the operating frequency of the antenna. The
size of the proposed antenna is reduced by about 50% compared to a conventional CP
slot-ring antenna and it displays a CP bandwidth of about 2.5%. The simulated and
measured results are presented, and they are in good agreement. The small size of the
antenna makes it very suitable for use in modern RF/microwave wireless systems which
require compact, low cost, and high performance circuits. Moreover, its CP behavior
makes it more attractive for applications such as satellite communications. The second topic in the thesis involves the design of a compact microstrip bandpass
filter using triangular open-loop resonators. A new compact three-pole microstrip
bandpass filter using four triangular open-loop resonators is presented. A fourth
resonator is placed to provide cross-coupling in the structure which gives a better skirt
rejection. The measured pass-band center frequency is 2.85 GHz. The filter demonstrates
about 7% bandwidth with insertion loss of less than 1 dB in the passband, a return loss
of greater than 15 dB and out-of-band rejection of greater than 30 dB. The simulated
and measured results are in good agreement. The proposed filter is very attractive for use
in modern wireless systems which require bandpass filters having compact size, low
insertion loss, high selectivity, and good out-of-band rejection.
13
Kwinana, Phumezo M. "A T-resonator technique for aperture plane admittance parameters of electrically short RF monopoles." Thesis, Stellenbosch : University of Stellenbosch, 2006. http://hdl.handle.net/10019.1/1501.
Full textAbstract:
Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2006.This thesis focuses on the coaxial-microstrip T-resonator measurement technique to determine the aperture plane capacitance and radiation resistance of electrically short monopoles above a finite ground plane at Radio Frequencies. The determination of these impedance parameters is of interest as they are needed in the Thévenin equivalent circuit of the monopole to establish the relationship between the monopole, the electromagnetic field within which it is immersed, and its surrounding medium properties. Electromagnetically short monopoles are used in various applications such as in permittivity and biomedical measurement techniques and near-field metrology. The coaxial-microstrip device allows the measurement of transmission coefficient nulls when connected to the network analyser. By measuring the frequency shift in transmission null points and analysing the results, the capacitance of short monopoles of various lengths can be obtained. The radiation resistance of the monopole can also be determined by comparing the depth of transmission coefficient nulls points at various resonant frequencies. Monopoles ranging from flush-mounted to various sizes of protruding centre conductors, both bare and insulated, are investigated in the frequencies ranging from 45 MHz to 3 GHz. The experimental results compare well with FEKO numerical predictions at the ranges where this technique is applicable. The technique is however not applicable near and beyond the resonant frequency of the monopole where it is considered to be electrically long. Measurements to obtain monopole impedance parameters were conducted by connecting the device to the HP 8510C Network Analyser. To enhance accuracy, the Network Analyser was calibrated using a high quality calibration kit with precisely defined standards. The technique used was found to accurately yield capacitances in the range of 0.0211 to 1 pF and radiation resistances in the range of 0.9245 to 12.1 Ohms. These results were obtained for monopoles of length 0.0062 < h/l < 0.24. Results from literature, viz. W.R Scott, R.W.P. King and L.J. Cooper, show radiation resistance in the ranges: 2.5 to 35 Ohms (0.079 < h/l < 0.22), 1.26 to 74.08 Ohms (0.026 < h/l < 0.28) and 5.59 to 74.98 Ohms (0.1 < 0.28) for electrically short monopoles. The results of this work are compared with those in the literature and show variations of less than 6%. A technique capable of accurately measuring capacitance and radiation resistance of the monopole at various lengths of protruding centre conductor has been developed. The capacitance for a flush probe compares very well (agreement is less than 6%) when compared with those obtained by the previous researchers. The technique is capable of yielding accurate results radio frequencies in the challenging low radiation resistance range around 1 Ohm.
14
Al-Yasir, Yasir, Yuxiang X. Tu, M. S. Bakr, Parchin Naser Ojaroudi, Abdalfettah S. Asharaa, W. Mshwat, Raed A. Abd-Alhameed, and James M. Noras. "Design of multi-standard single/tri/quint-wideband asymmetric stepped-impedance resonator filters with adjustable TZs." IET Microwaves, Antennas & Propagation, 2019. http://hdl.handle.net/10454/17154.
Full textAbstract:
YesThis study presents an original asymmetric stepped-impedance resonator filter combined with meander coupled-line structures and enabling the realisation of finite transmission zeros (TZs) and the implementation of multi-band bandpass filters. The meander coupled sections (MCSs) tune the TZs and resonant frequencies: with higher-order spurious frequencies cancelled by the TZs, a single wideband with wide stopband from 1.18 to 1.84 GHz is possible. Furthermore, by positioning the finite TZs between the high-order spurious frequencies and adjusting the coupling strength between resonators, a quint-wideband filter can be realised, with centre frequencies of 1.19, 4.29, 5.43, 6.97, 9.9 GHz and fractional bandwidths of 31.9, 15.4, 15.8, 4.3, 39.2%, respectively. More importantly, two filters with single/quad-wideband performance can be realised by tuning the parameters of the MCS, and therefore they can be designed separately by using only one original structure. The triple-wideband filter is realised with the help of the asymmetric parallel uncoupled microstrip section. These filter structures enjoy the advantage of single/multi-band versatility, structure reusability and simplicity. The good in-band and out-of-band performance, low loss and simple structure of the proposed single/tri/quint-wideband filters make them very promising for applications in future multi-standard wireless communication.
European Union's Horizon 2020 research and innovation programme under Grant agreement H2020-MSCA-ITN-2016 SECRET-722424.
15
Vágner, Petr. "MIKROPÁSKOVÉ FILTRY S VYUŽITÍM NARUŠENÉ ZEMNÍ PLOCHY." Doctoral thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-233479.
Full textAbstract:
The thesis deals with the microstrip filter design using defected ground structure (DGS). The difference between standard asymmetric microstrip technique and DGS is in using the structures etched in the microwave substrate ground plane. The DGS resonant characteristics are then used in filter design. The thesis consists of three factual parts. The first one (chapter 4) introduces the use of the DGS resonators in the lowpass filter design. It involves experimental analysis of one type of the lowpass filter. The second part (chapter 5) deals with a novel microstrip lowpass filter design method using DGS. The proposed method is verified by simulations and several samples are realized and measured. Finally, the third part (chapters 7 and 8) deals with the bandpass filter design using specific defected ground structure as a resonator. The resonators are used in a coupled resonator structure. Filters of various orders and resonator configurations are designed and simulated. A combination of the DGS resonators and half-wavelength microstrip resonators is introduced as well. Selected samples are realized and measurement results are compared with simulations.
16
Palomo, Timothy Joseph. "Microfluidically Reconfigurable Frequency-Agile RF Filters with Wide Frequency Tuning Range and High Power Handling Capability." Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6124.
Full textAbstract:
Radio Frequency (RF) filters are among the key components of today’s multifunctional devices and test equipment. However, the multifuctionality need significantly drives the required filter number and causes large areas to be allocated for filters. To alleviate this issue, over the recent years, reconfigurable filters have been proposed as an attractive alternative. Nevertheless, existing reconfigurable filter technologies demonstrate degraded performances in terms of loss, frequency tunability bandwidth, and power handling capability. This work investigates, for the first time, microfluidic based reconfiguration techniques for implementation of RF bandpass filters. Specifically, microfluidics is shown to provide mechanisms for achieving compact RF bandpass filters that can exhibit low loss, high power handling, and high frequency tunability. First, we present the utilization of liquid metals for realization of a frequency-agile microstrip bandpass filters consisting of broadside coupled split ring resonator (BC-SRR). In this design approach, one of the loops of the BC-SRR is realized from liquid metal to be able to microfluidically change the resonator shape and associated resonance frequency. The filter exhibits a 29% frequency tunable range from 870 MHz to 650 MHz, with insertion loss <3 >dB, over the entire frequency tuning range, for a fractional bandwidth (FBW) of 5%. To the best of our knowledge, this filter design is the first in available literature that shows a continuously frequency reconfigurable microfluidic RF band-pass filter. To overcome the oxidization and lower conductivity issues associated with liquid metals and enhance the frequency tuning range further, subsequently, we introduce a filter design technique in which microfluidically repositionable metallized plates are utilized within microfluidic channels with ultra-thin insulator walls. Specifically, this technique is employed to design a two pole microstrip bandpass filter where microfluidically repositionable metalized plates are used to capacitively load printed open loop resonators. To operate the filter (and control movement of multiple metalized plates) with a single bi-directional micropump unit, a strategically designed meandered microfluidic channel is implemented. The filter exhibits a 50% tuning range (from 1.5 GHz to 0.9 GHz), with an insertion loss15 W input power without the need of thick ground planes and/or heat sinks.
17
Klegová, Hana. "Nízkošumové zesilovače pro pásmo 1-3 GHz." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-316424.
Full textAbstract:
This masters thesis deals with low noise amplifier design for frequency range 1 GHz - 3 GHz. There is a short theoretical introduction in the first part of the thesis. There are described parameters and properties of transistors and general two-ports. Description of the noise characteristics two-ports follows. The next capture contains design of two-stage amplifiers. One of them is with a microstrip filter between stages and the second one is with combline filter on input of the amplifier. The amplifiers and the microstrip filter were designed in program ANSOFT Designer. The design of combline filter was realised in program CST Microwave Studio. Both amplifiers ware made and their properties ware compared with simulations.
18
Волошин, Антон Олександрович. "Мікромеханічно перелаштовувані антенні елементи НВЧ." Doctoral thesis, Київ, 2020. https://ela.kpi.ua/handle/123456789/36406.
Full textAbstract:
Дисертаційна робота присвячена розробленню способів мікромеханічного перелаштування робочої частоти діелектричних резонаторних та мікросмужкових антенних елементів, що основані на перерозподілі електромагнітного поля внаслідок мікропереміщень складових частин резонаторів та, на відміну від існуючих способів,
забезпечують перелаштування частоти в діапазоні до 30 відсотків без внесення додаткових дисипативних втрат електромагнітної енергії. На відміну від електричних,
магнітних і оптичних способів перелаштування, мікромеханічний спосіб не вносить
додаткових втрат та відрізняється широким діапазоном перелаштування.
Встановлено закономірності впливу електрофізичних та геометричних параметрів
антенних елементів на частотні, енергетичні та випромінювальні характеристики антен, а також сформульовано умови підвищення чутливості робочої частоти до переміщень та розширення діапазону перелаштування частот.
На основі аналітичного розв’язку електродинамічної задачі для одновимірної діелектричної неоднорідності встановлено закономірності перелаштування резонансної
частоти за рахунок переміщення складових частин діелектричного резонатора. Встановлені закономірності узагальнено теоретичними та експериментальними дослідженнями тривимірних діелектричних резонансних структур.
На основі теорії кіл з розподіленими параметрами запропоновано схемну модель
мікросмужкового резонатора, включеного як кінцеве навантаження лінії, що спрощує процес проектування антенного елемента та оптимізації його характеристик.
19
CHEN, YI-YUAN. "I : approche spectrale des modes rayonnants dans une ligne microfente. ii: traitement electromagnetique du pseudo court-circuit microfente." Rennes, INSA, 1988. http://www.theses.fr/1988ISAR0002.
Full textAbstract:
L'objet de cette these est de decrire les caracteristiques des modes continus et discrets de la ligne microfente et de la couche dielectrique avec plan de masse. La source des modes continus est une onde plane tridimentionnelle. On presente la relation liant le spectre de fourier au spectre angulaire de l'ordre plane. Le flux de puissance est calcule pour les 2 nodes. On verifie la relation d'orthogonalite entre modes pour les cas degenere et non degenere. On presente l'analyse modale du court-circuit de la ligne a fente et les equations integrales couplees resultantes sont traites numeriquement. Un modele en cavite est egalement developpe pour resoudre le probleme de discontinuite et pour valider les resultats precedents
20
Limaye, Aparna U. "Size reduction of microstrip antennas using left-handed materials realized by complementary split-ring resonators /." Link to online version, 2006. https://ritdml.rit.edu/dspace/handle/1850/2428.
Full text
21
Ali, Abdulbaset M. M. "Gain enhancement of microstrip patch antenna using dielectric DNG superstrate /." Online version of thesis, 2009. http://hdl.handle.net/1850/11170.
Full text
22
Fulford, Andrew Richard Wentworth Stuart M. "Conductor and dielectric property extraction using microstrip tee resonators." Auburn, Ala., 2005. http://repo.lib.auburn.edu/2005%20Summer/master's/FULFORD_ANDREW_7.pdf.
Full text
23
Kerouedan, Julien. "Conception et réalisation de sondes hyperfréquences pour la détection de micro-fissures de fatigue à la surface des métaux." Brest, 2009. http://www.theses.fr/2009BRES2058.
Full textAbstract:
La fatigue mécanique et thermique des structures métalliques est l’une des altérations majeures dans les centrales de production d’énergie. Une détection précoce des défauts de surface par des procédés de contrôle non destructif (CND) permet une maintenance préventive pertinente des installations en évitant d’avoir à démonter ou remplacer des composants sains. Actuellement, la majorité des solutions automatisées de CND est basée sur des techniques utilisant les ultrasons ou les courants de Foucault. Cependant, malgré leurs sensibilité et résolution spatiale élevées, ces méthodes ne sont pas nécessairement adaptées à la détection de tous les défauts de surface rencontrés en pratique. Les limites des méthodes de contrôle conventionnelles par courants de Foucault et ultrasons pour détecter des micro-fissures de surface dans les métaux justifient l’intérêt d’évaluer le potentiel de nouvelles techniques. Les travaux de thèse présentés dans ce mémoire se focalisent sur l’apport des méthodes microondes, Dans ce document, nous démontrons la faisabilité de la détection de micro-fissures de surface dans les métaux à l’aide de sondes micro-ondes résonantes en champ proche. En particulier, à partir de simulations et de mesures réalisées sur des maquettes de test contenant des entailles électroérodées rectangulaires, nous mettons en évidence la sensibilité et la résolution spatiale élevées des sondes originales de type filtre Dual-Behavior Resonator (DBR)The fatigue and ageing of metal materials under operation conditions are major concerns in energy production plants. An early and non-destructive diagnostic of surface defects would allow one to carry out relevant preventive maintenance operations without dismantling or prematurely changing healthy components. Nowadays, most of the automated non-destructive testing (NDT) solutions available to detect the surface-breaking defects are based on ultrasound or eddy current techniques. Despite their high sensitivity and spatial resolution, they are unable to meet all the requirements of every real situation. Consequently, in order to supplement the available acoustic and electromagnetic NDT toolkits, it sounds relevant to evaluate the potential of new techniques to detect micro-cracks on metal surfaces. The aim of this work is the development of microwave methods allowing the detection of surface-breaking defects on metals. In this report, we demonstrate how micro-cracks at the surface of metals can be detected and imaged by using near-field microwave resonators. In particular, we present simulation data and measurement results carried out on mock-ups with EDM rectangular surface notches highlighting the high sensitivity and spatial resolution of the original dual-behavior resonator (DBR) filter probes
24
Ledezma, Luis Manuel. "A Study on the Miniaturization of Microstrip Square Open Loop Resonators." Scholar Commons, 2011. http://scholarcommons.usf.edu/etd/3202.
Full textAbstract:
A miniaturization technique that allows the size of microstrip square open loop resonators to be reduced by more than 80% is presented and studied. The technique is based on the loading of the resonator with a series surface mount capacitor. It is shown that this technique allows the design of microwave bandpass filters with a wider stopband when compared with conventional designs. It is also proved that the insertion loss of the miniaturized filter is not degraded, but in fact can be maintained or even enhanced by the miniaturization process; this is true whenever the quality factor of the lumped capacitor is higher than the quality factor of the microstrip resonator. Finally, the feasibility of using the effect of the capacitor loss in the miniaturized resonator quality factor as a method to measure the effective series resistance of surface mount capacitors is studied, and recommendations towards its implementation are presented.
25
Zhou, Jiafeng. "Novel compact microwave resonators and filters in microstrip and coplanar structures." Thesis, University of Birmingham, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.409041.
Full text
26
Haidar, Jihad. "Commande optoélectronique d'atténuateurs, de résonateurs et de filtres microondes réalises sur substrat silicium." Grenoble INPG, 1996. http://www.theses.fr/1996INPG0094.
Full textAbstract:
La commande optique de dispositifs microondes, qui exploite l'injection optique des porteurs dans un semiconducteur, apporte de nombreux avantages vis-a-vis de l'electronique conventionnelle. La presente etude avait pour objectif d'etendre cette commande a des dispositifs, realisant des fonctions complexes, tels que les attenuateurs, resonateurs et filtres microondes. Les structures etudiees ont ete realisees sur du silicium en technologie ligne microruban. Nous avons exploite principalement la charge complexe induite entre le ruban et le plan de masse par illumination optique. Nous avons demontre que la lumiere cree principalement une charge resistive aux faibles puissances, mais qu'une composante reactive apparait aussi d'une maniere nette pour les puissances optiques elevees. L'effet resistif a ete mis en application dans la realisation d'un attenuateur microondes en technologie microruban, reglable par la simple commande optique. Nous avons demontre sur un premier prototype une plage d'attenuation superieure a 10db dans la bande c. Quant a l'effet reactif, nous avons introduit une commande supplementaire qui permet de le renforcer. Il s'agit de polariser le plasma photo-induit par une tension continue qui se superpose au signal hyperfrequences. Nous avons accorde la frequence de differents resonateurs par cette nouvelle double commande optoelectronique. Ces accords, sont, a notre connaissance, de loin les plus larges jamais reportes parmi les accords electriques. En effet, nous avons mesure des deplacements de la frequence de resonance de l'ordre de 30% en dessous de la frequence de resonance en l'absence d'illumination. L'etude est plutot de nature experimentale, mais des modeles theoriques simples ont ete developpes pour tenter d'expliquer les differents phenomenes nouveaux mis en evidence experimentalement. Nous avons reussi a etablir, d'une maniere satisfaisante en premiere approche, le lien entre les parametres physiques du semiconducteur d'une part et le schema equivalent du plasma photo-induit deduit de la reponse microondes du dispositif d'autre part
27
Šmarda, Marek. "Miniaturní anténa pro mobilní aplikace." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-219975.
Full textAbstract:
This work deals with the most famous constructions of planar antennas. The work analyses selected methods of connecting planar antennas' charging with the possibility of impedance adaptation. An important part of the work consists of description of techniques for increasing bandwidth and conversely techniques for reducing the dimensions which are important for the design of planar antennas for mobile devices. The antennas were designed by means of theoretical basis and their properties were examined in the electromagnetic field simulator. The selected antenna model was constructed and its parameters were measured experimentally. The matching circuit for the antenna to tune it to different resonant frequencies was designed and constructed.
28
U-yen, Kongpop. "Microwave filters with high stop-band performance and low-loss hybrid developement." Diss., Available online, Georgia Institute of Technology, 2006, 2006. http://etd.gatech.edu/theses/available/etd-11162006-111102/.
Full textAbstract:
Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2007.Tentzeris, Manos, Committee Member ; Wollack, Edward, Committee Member ; Cressler, John, Committee Member ; Papapolymerou, Ioannis, Committee Chair ; Laskar, Joy, Committee Co-Chair ; Ayazi, Farrokh, Committee Member.
29
Sousa, Neto Marinaldo Pinheiro de. "Um estudo de metamaterial em antenas de microfita." Universidade Federal do Rio Grande do Norte, 2014. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15247.
Full textAbstract:
Made available in DSpace on 2014-12-17T14:55:19Z (GMT). No. of bitstreams: 1
MarinaldoPSN_TESE.pdf: 2731148 bytes, checksum: 7c2caa3355d4d42f0702baf0d147bf97 (MD5)
Previous issue date: 2014-04-25Universidade Federal do Rio Grande do Norte
Metamaterials have attracted a great attention in recent years mostly due to their electromagnetic properties not found in nature. Since metamaterials began to be synthesized by the insertion of artificially manufactured inclusions in a medium specified host , it provides the researcher a broad collection of independent parameters such as the electromagnetic properties of the material host. In this work was presents an investigation of the unique properties of Split Ring Resonators and compounds metamaterials was performed. We presents a theoretical and numerical analysis , using the full-wave formalism by applying the Transverse Transmission Line - LTT method for the radiation characteristics of a rectangular microstrip antenna using metamaterial substrate, as is successfully demonstrated the practical use of these structures in antennas. We experimentally confirmed that composite metamaterial can improved the performance of the structures considered in this thesis
Os metamateriais tem atra?do uma grande aten??o nas ?ltimas d?cadas, principalmente devido as suas propriedades eletromagn?ticas n?o encontradas na natureza. Desde que os metamateriais passaram a ser sintetizados atrav?s da inser??o de inclus?es artificialmente fabricadas num meio hospedeiro especificado, isto propicia ao pesquisador uma larga cole??o de par?metros independentes, tais como as propriedades eletromagn?ticas do material hospedeiro. Neste trabalho foi realizada uma investiga??o das propriedades ?nicas dos Ressoadores em Anel Partido (Split Ring Ressonators - SRR) e dos metamateriais compostos. Apresentou-se uma an?lise te?rica e num?rico-computacional, utilizando o formalismo de onda completa atrav?s da aplica??o do m?todo da Linha de Transmiss?o Transversa LTT, para as caracter?sticas ressonantes de uma antena de microfita com patch retangular utilizando substrato metamaterial, assim como ? demonstrado com sucesso ? utiliza??o pr?tica dessas estruturas em antenas. Esta utiliza??o pr?tica ? confirmada experimentalmente
30
Zhang, Rui. "Novel Planar Microstrip and Dielectric Resonator Filters." Thesis, 2007. http://hdl.handle.net/10012/2753.
Full textAbstract:
Microwave filters possessing various forms are essential components in radar, satellite, and mobile communication systems. Increased demands for low-loss, miniature filters that can be mass produced at low cost have provided a significant challenge reinforcing the need for improving or even replacing the conventional microwave filters.
In recent years, the concept of Photonic/Electromagnetic Bandgap (PBG/EBG) structures has attracted the attention of the microwave engineering community. The main feature of PBG/EBG structures is the existence of a bandgap in the frequency spectrum of a propagating photonic/electromagnetic wave. The motivation for adopting EBG structures stems from their capability to eliminate unwanted wave propagations in various microwave devices.
This thesis investigates and proposes novel planar microstrip filters employing EBG structures in the form of slots etched on the ground plane. Such filters are not only compact, but also can improve the RF performance in both the passband and the stopband. This proposed concept is further extended to implement low-loss tunable lowpass filters, both digital and analogue, by integrating tuning elements directly into the slots. Transmission line circuit models are developed to design the proposed microstrip filters and tunable lowpass filters. To verify the concept and the validity of the developed circuit models, theoretical and experimental results are presented and carefully compared.
Currently, dielectric resonator (DR) filters have been widely employed in wireless and satellite communication systems. Over the past two decades, tremendous progress has been made to reduce the size, and enhance the in-band and out-of-band performance of DR filters. However, the current approaches for implementing DR filters are relatively expensive and hardly amenable to mass production. Cost reduction remains a key limiting factor that needs to be addressed now.
A new configuration of DR filters is presented in this thesis. The novel concept simplifies the assembly, integration, and alignment of DR filters, significantly reducing production time and costs. Not only is the design of the proposed multi-pole DR filters and diplexers examined, but also the fabrication technique. The experimental measurement results confirm the validity of the theoretical designs of the new filters, which makes this concept very attractive for further applications in both wireless and satellite communication.
31
吳鈞弘. "Highly Selective Microstrip Miniaturized Hairpin Resonator Filters." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/50185970189701645580.
Full textAbstract:
碩士國立臺灣科技大學
電子工程系
90
In this thesis, miniaturized hairpin resonators are studied. Two design equations for odd-mode and even-mode resonance are derived from a network model. The size and spurious response of this type of resonators are then minimized and controlled based on these two equations. The coupling coefficients for the three basic coupling structures are then determined with respect to the specifications. The full-wave simulator is used in designing the miniaturized hairpin resonators and the three basic coupling structures. A single transmission zero is realized by the cross coupling in the structure, which can improve the skirt selectivity of the filter. The synthesis technique for the design of filter is described. Design examples of a four-pole filter with a fractional bandwidth of 5% at 2.48GHz is presented. Both the theoretical and experimental performance are presented and consistent.
32
Ching-Min, Li. "The Ferromagnetic Resonance Effect on Fe Microstrip Resonator." 2006. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0016-1303200709265780.
Full text
33
Li, Ching-Min, and 李清閔. "The Ferromagnetic Resonance Effect on Fe Microstrip Resonator." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/46552164571561267264.
Full textAbstract:
碩士國立清華大學
光電工程研究所
94
The physical property measurement of microwave materials is an important research topic to determine the accurate parameters in the design of circuit components. The purpose of this research is to present how the ferromagnetic resonance (FMR) interacts with the structure resonance and propose a new method to measure the saturation magnetization, the anisotropic field, and the conductivity of magnetic films. The T-microstrip resonator was fixed on the universal test fixture that was connected with the HP 8722D vector network analyzer, and applied an uniform magnetic field on the films in various directions. Then, the transmission coefficient S21 parameters were measured at various magnetic fields by a HP 8722D vector network analyzer. When the magnetic field was increased, the deep of the transmission coefficient S21 increased initially and then decreased; in addition, the resonance frequency shifted to the right and then shifted to the left. The variant range of the deep was about 4dB and the shift range of the frequency was from –0.04GHz to 0.04GHz. The simulated anisotropic field Ha was about -379.7 Gauss and the saturation magnetization Ms was 1255.7 Gauss. These results suggest that this method simplifies the procedure for studying the physical properties of magnetic thin films.
34
Chen, Yih-Jang, and 陳奕璋. "Highly Selective Microstrip Square Open-loop Resonator Filters." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/27537022104706247795.
Full textAbstract:
碩士國立臺灣科技大學
電子工程系
89
In this thesis, we use the quasi-elliptic filter synthesis method, which produces a pair of zeros at finite frequencies to design highly selective bandpass filters. In addition, we use the microstrip square open-loop resonator as a basic unit to implement this kind of filter. We take advantage of cross coupling property of appropriately arranged resonators to produce a pair of finite frequency zeros. The key of designing this filter is to control the coupling and coupling character between two resonators precisely. Hence three basic resonator-coupling structures and the factors that affect the coupling are discussed. Then, two possible signal-feeding structures are discussed, too. Finally, we implement both four-resonator and eight-resonator filters, and the simulation results are in good agreement with the measurement results.
35
SUNG, NAN-CHANG, and 宋南昌. "Microstrip Dielectric Resonator Filter with the Photonic Bandgap Structures." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/96912158918744378810.
Full textAbstract:
碩士國立臺北科技大學
電腦通訊與控制研究所
89
At microwave frequency band, general lump elements are inadequate for general usage. Many microwave elements are developed to be used at high frequency band. Dielectric resonators (DRs) , which have low dielectric loss, high Q value and well frequency temperature coefficient are extensively used in many microwave circuits. Due to the cylindrical shape of dielectric resonators, the lowest resonant mode is HEM mode. In this thesis, TE mode that has the highest Q is selected to design the DR filter. The DR filter consisted of two dielectric resonators placed inside a resonant cavity, and microstrip is used as the coupling mechanism. Since many modes are excited in a DR filter, the higher excited modes turn into spurious modes which contributed to interferences. It is than an important issue in designing ways to suppress spurious responses. In this thesis, PBG structures cascaded to the DR filter are designed to suppress the spurious responses. PBGs consisted of microstrip structures with etched holes on the ground plane. PBGs have the characteristics of wide and deep stopband. To cascade the designed DRF and PBGs may suppress the spurious responses by at lower -15 dB. Due to the wide range and easy fabrication at stopband, PBG structures have been proposed as a novel mean for accomplishing the suppressing by providing a broad rejection band.
36
Kuo, Hsin-I., and 郭信宜. "Novel Miniaturized Bandpass Filters with Combined Microstrip-CBCPW Resonator." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/78484613222162048683.
Full textAbstract:
碩士國立交通大學
電信工程系所
94
This thesis presents the novel miniaturized bandpass filters with combined microstrip-CBCPW (conductor-backed coplanar waveguide) resonator. The filters are designed by coupling coefficient method. Using this method the external quality factors and the internal coupling coefficients can be obtained. Then, utilizing EM simulation software obtains relative resonator dimensions corresponding to previously determined external quality factors and the internal coupling coefficients. The whole filter design procedure is simple and concise. In this thesis, combline, interdigital, folded and spiral bandpass filters with Chebyshev response are designed. Finally, a quasi-elliptic filter synthesis method is used to design highly selective narrow bandpass filters with a pair of finite frequency transmission zeros.
37
Tsai, Wen-Ming, and 蔡文銘. "Multiple Stepped Impedance Microstrip Resonator Bandpass Filters for Suppression." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/78230197379315392390.
Full textAbstract:
碩士國立交通大學
電信工程系
91
In this thesis, multiple stepped impedance resonators (MSIRs) are proposed to design parallel-coupled line filters for suppressing the spurious harmonic response at twice the passband frequency (2f0). The line spacing and line width of each coupled stage follow those obtained by the traditional synthesis method. Only the width of certain portion of resonator is changed. Furthermore, utilizing the inherent transmission zero of the input and output coupling stages, the stopband characteristics of the filter can be further enhanced. Some experimental filters are measured to demonstrate the design, and their responses show a good agreement with the simulation results.
38
Yu, Hong-Siang, and 余弘翔. "Balanced WB/UWB BPF Designs Using Microstrip and Slotline Resonator." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/30984480923089003318.
Full textAbstract:
碩士國立彰化師範大學
電信工程研究所
99
The objective of this thesis is to study and design balanced wideband and ultra-wideband (UWB) bandpass filters (BPFs). The proposed BPFs were designed using microstrip, slotline, or hybrid microstrip-slotline configurations. The research work is divided into three parts. In the first part, uniform-impedance resonators (UIRs) were used to design a third-order balanced BPF which has differential-mode (DM) wideband response and good common-mode (CM) rejection in the desired passband. The DM wideband response is achieved by locating evenly the three split modes (which result from strong coupling) of the resonators in the desired DM passband. Out-of-band spurious modes in the higher frequency region are suppressed by degrading impedance matching which is obtained by tuning the length of the open stub loaded on the second resonator. In CM operation, the signal is attenuated by separating resonant frequencies of the intermediate-stage resonators to obtain good CM suppression. In the second part of this thesis, a microstrip-fed dual-ring-type slotline resonator is proposed to construct a balanced UWB BPF. Strong signal coupling is achieved by using microstrip-to-slotline transition (MST) structure for which the feeding point is located one quarter-wavelength away from the short-circuited end of the slotline and the same distant away from the open-end of the microstrip line. To obtain DM UWB response, besides using the MST feeding structure, we locate the first three resonant modes of the slotline resonator (SLR) in the passband to make it uniform and wide enough. On the other hand, to suppress CM signals, the inner, coupled sides of the two ring SLRs are made inclined to reduce the degree of coupling, and meanwhile, we implement two wave-trapping resonators of different lengths around the feeding lines to produce two transmission zeros and hence to further filter out the unwanted CM signals. In the final part of this thesis, a UWB BPF was designed using a straight SLR which is deployed symmetrically with the plane of symmetry (POS). Again, to achieve UWB response, the first three resonant modes of the SLR are located in the in the DM passband. In addition, to obtain better signal transmission, the SLR is fed at the position which is one quarter-wavelength away from its end by microstrip lines that are placed across the POS. Thus when excited differentially, the microstrip feeding lines are equivalently short-circuited along the POS, rendering a large current distribution and large surrounding electromagnetic field around that short-circuited end. Similar to the case addressed in the second part, this will result in strong coupling between the microstrip feeding lines and the SLR. As the UWB BPF is in CM operation, the POS is virtually open, the half SLR structure is thus incomplete and no magnetic current will flow in it. Such an incomplete SLR can prevent signals transmission from the input port to the output port through the SLR, thus gives a very effective CM suppression. The designed balanced wide band and UWB BPFs are simulated for characteristics study and verified by measurement. Results show that the designed balance wideband and UWB BPFs are feasible for application in MB-OFDM and UWB systems. The proposed design technique could serve as a useful reference for researchers and engineers working in this and related areas.
39
Lin, Yen-Chung, and 林沿鍾. "Quality Factor Measurement of Dielectric Resonator Through Microstrip Line Coupling." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/86692727166109963668.
Full textAbstract:
碩士國立臺灣大學
電信工程學研究所
96
Dielectric resonator (DR) is made of high dielectric constant materials and acts as a cavity enclosed by perfect magnetic conductor (PMC). Because of the high dielectric constant, its dimensions are much smaller than other types of resonators at the same frequency. Take the 8700 series DRs offered by Trans-Tech for example. Its εr 30, hence its electrical length is about 5.5 times smaller than that of an air-filled cavity. Besides, dielectric resonator has ultra high quality factor, resulting in a quite narrow operating bandwidth. Therefore, dielectric resonator is widely used in the microwave and millimeter wave circuits, for example, antennas, filters and oscillators. In many aspects, the quality factor of dielectric resonator is the major characteristic to be taken into account in the microwave circuit design. Especially in filter design, for example, the method given in [1], after giving the design parameters of a filter, the circuit layout would meet the design requirements by measuring the first-order external Q of the resonator. In other words, an accurate and effective quality factor measurement becomes an important issue in the applications of dielectric resonator. For this reason, this thesis uses the method developed in [2]. In Chapter one, we give a brief description of quality factor and dielectric resonator, then present some basic measurement models [3] based on the simple equivalent circuits. After the discussion about the advantages and disadvantages of this model, we then take more complicated situations into account based on [4] and describe in Chapter two. Finally, we consider the situation about the dielectric resonator coupled to a microstrip line in Chapter three with simulation and measurement results.
40
Liang, Cheng-Hsien, and 梁正憲. "Miniaturization of Microstrip λ/4 Stepped-Impedance-Resonator Filters Using Low Impedance Microstrip with Inserted Ground Strips." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/t5war5.
Full textAbstract:
碩士國立交通大學
電信工程系所
95
A new method to miniaturize microstrip step impedance resonator structure is proposed in this theses. Inserting ground strips in the low impedance microstrip segment results in a high effective capacitance that makes the characteristic impedance lower. Therefore, the characteristic impedance of the microstrip line is mainly controlled by the signal strips and the inserted ground strips in coplanar manner. The concepts and characteristics of this modified resonator structure are described in detail. Practical applications for planar bandpass filters employing the features of this resonator structure are discussed and fabricated. Besides, additional cross coupling structure which produces a pair of transmission zeros near the passband is also introduced to improve the skirt characteristics. Both simulated and measured results are presented.
41
Lai, Lian-Shing, and 賴良星. "Physical properties of YBCO microstrip ring resonator with a split gap." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/17287449071313649079.
Full textAbstract:
碩士國立交通大學
電子物理系
89
The thesis can be divided into three parts. The first is to investigate the microwave properties of high-Tc superconductor ring resonators with various split gap structures. The second part is to use the microwave data of wave impedance, from which the important physical parameters such as Q values, surface impedance, penetration depth and energy gap, have been deduced. The third part attempts to delineate the physical properties of YBCO thin films with various oxygen contents. A detailed process of fabrication of the epitaxial YBCO thin films as well as the microwave ring resonators will be described at first. Using these resonators the generation of the frequency response can be justified by the computer simulation of Ansoft software, in which a perfect conductor, instead of the superconductor, has been taken. From the experimental observation, the case of the superconducting ring resonator appears the resonate frequency as same as that in the conductor. Although both of them have the behavior of the same frequency response, it has possessed the Meissner effect for the superconductor. Incidentally their resonate frequencies are determined by their own boundary conditions. Finally a number of salient results in the microwave measurement allow us to get several important parameters, with which the basic nature of the high-Tc superconductivity in the underdoped case can be elucidated. For instances, the energy gap 2Δ0/kBTc=8±0.2 and Fermi liquid correction factor <1, can be yielded. Moreover, the reduced temperature T/Tc dependence of the superfluid density is shown to be independent of doping concentration, which reflects a fact that the Cu-O chain in the YBCO material is irrelevant in the consideration of superconductor properties, and the pairing mechanism occurs on the CuO2 planes thoroughly.
42
Reppel, Michael [Verfasser]. "Novel HTS microstrip resonator configurations for microwave bandpass filters / von Michael Reppel." 2000. http://d-nb.info/960169245/34.
Full text
43
Elmegri, Fauzi, Chan H. See, Raed A. Abd-Alhameed, and Peter S. Excell. "Dielectric resonator antenna design for lower-UWB wireless applications." 2013. http://hdl.handle.net/10454/9649.
Full textAbstract:
NoA small dielectric resonator antenna has been designed for ultra wideband (UWB) communication system applications. The antenna element is a rectangular low permittivity ceramic block, with a dielectric constant of 9.4, and the modified T-shaped feed network includes a 50 ohm microstrip line to achieve strong coupling, and some bandwidth enhancement. The antenna performance is simulated and measured over a frequency band extending from 3100 MHz to 5500 MHz; the impedance bandwidth over this interval is 55.8% with VSWR <; 2, making the antenna suitable for UWB applications.
44
Chang, Cai-Fu, and 張財富. "The design of 2.4 GHz VCO using microstrip line resonator and 5.2 GHz VCO using substrate-integrated waveguide cavity resonator." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/23510211616360294564.
Full textAbstract:
碩士臺灣大學
電子工程學研究所
96
This thesis presents the designs of 2.4GHz and 5.2GHz voltage control oscillators by two kinds of microwave resonator. The 2.4GHz VCO uses microstrip line resonator and the 5.2GHz VCO uses substrate integrated waveguide (SIW) cavity resonator. Low pass filters are added at output port of each VCO to improve its harmonic rejection. The simulated results for both VCOs are presented and their performances are compared with other VCOs.
45
Chang, Cai-Fu. "The design of 2.4 GHz VCO using microstrip line resonator and 5.2 GHz VCO using substrate-integrated waveguide cavity resonator." 2007. http://www.cetd.com.tw/ec/thesisdetail.aspx?etdun=U0001-2011200700364000.
Full text
46
Teh, Chen-Tai, and 葉鎮臺. "The Analysis and Simulation of Microstrip-Fed Dielectric Resonator Antenna Using FDTD Method." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/57932376275201528202.
Full textAbstract:
碩士國立中山大學
電機工程學系研究所
99
Dielectric resonator antennas(DRAs) offer some attractive characteristics over conventional microstrip antennas, such as small size, low profile, light weight, ease of excitation, and high radiation efficiency at higher frequency bands. Since DRAs attract more and more attention, theoretical analysis have been insufficient to simulate various configurations of dielectric resonator antennas. Therefore some researchers introduce numerical methods to analyze DRAs, such as Finite Difference Time Domain (FDTD) method, Method of Moment (MoM), Finite Element Method (FEM). In this author, we apply two kinds of methods, including FDTD and MoM, to analysis DRA and compare the results applied these two methods. Then we simulate various configurations of dielectric resonator antennas using FDTD method. About designing the DRA construction, in this author we applied an equivalent approach to solve approximate dimensions of DRAs, and then we obtain accurate dimensions using FDTD method. In this author，a DRA work at 5.8GHz have been proposed, then we using a L-shaped patch to increase impedance bandwidth. Above all, we hope to built a fast and accurate procedure to solve the resonant frequency, bandwidth, and far field pattern of DRAs. And to supply the engineer to reduce time consume in design DRAs.
47
Zeng, Huey-Kai, and 鄭慧愷. "Study of Microwave Properties of the YBCO Thin Film Using Microstrip Ring Resonator." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/63121601204478223984.
Full textAbstract:
博士國立交通大學
電子物理系
89
Superconducting ring resonators with or without a gap were successfully fabricated using double-side YBa2Cu3O7-δ (YBCO) films deposited on LaAlO3 (LAO) substrates. Measurement of the microwave surface impedance, Zs(T) = Rs(T) + jXs(T), allows us to determine the complex conductivity, s(T), in the ab-plane of YBCO thin films. Using results of Zs(T) and s(T) together with the modified two-fluid model, the temperature and frequency dependences of London penetration depth and quasiparticle scattering lifetime can be systematically studied by varying the oxygen contents of the same resonator structure. Some salient results found in the dissertation are listed below: I.Form the measurement of the resonance frequency and thus the phase velocity in the ring resonator the dielectric constant of the LAO substrate was estimated to be er @ 25.7 at 5 K. II.By placing a narrow gap located at symmetrical position with respect to the coupling lines in the ring resonator, we observed that original fundamental resonating modes splits into a dual-mode with different resonating frequencies. One occurs at one half and the other at three halves of the original frequency, respectively. It leads us to easily provide some behaviors of frequency dependence of several physical quantities with the same microstructure in a unique manner. Moreover, an equivalent mutual-inductance circuit model is suggested to account for the occurrence of the dual mode resonance. The validity of the model let us easily give the justification of the relation between the surface loss and frequencies, i.e., Rs µ w2. III.(a) For fully oxygenated case (d = 0.05), the resonator exhibits a quality factor Q > 104 around 15 K, and Dl(T) = l(T)-l(5K) displays a linear behavior (Dl/T = 4.8 Å/K) at the low temperature regions (T < Tc/3). With increasing d (e.g. d = 0.2, 0.4), although Dl is still linear in temperature, the slope changes with increasing oxygen deficiency. (b) Following the model suggested by Scalapiano et al., the energy gap could be derived and the value of the ratio of energy gap to the critical temperature, we found 2D(0)/kBTc, around 5.3±1.4, which is independent of the doping concentrations. (c) The function of l(T) versus the normalized temperature T/Tc exhibits a universal form. It implies a unique high-Tc mechanism in the underdoped cuprate, which is occurred in the CuO2 planes only. The values of l(5K) with various oxygen contents are 150±14 (d = 0.05), 216±16 (d = 0.2) and 282±20 nm (d = 0.4), respectively and found to be independent of frequencies. IV.The scattering rate of the low-excitation quasiparticles versus normalized temperature appears as a universal exponential form, 1/t(T) µ eaT/Tc. The relaxation time in the low temperature limit is around t @ 3.76 ´ 10-11 sec, which is 500 times more than that at the critical temperature. Then the energy due to such scattering from the uncertainty principle is found to be around 1.75 ´ 10-2 mev. V.The real part of the complex conductivity s(T) after reaches a plateau in the low temperature limit. The effect is clearly contradicted to that found by a single crystal. We prospect that it might be a lot of dislocation distributed in the ab plane for our samples thin films. Such defect of dislocation takes a great effect on the quasiparticle scattering in the low temperature limit. We also found that the residual conductivity depends upon the doping concentration of oxygen contents. VI.The current model suggested by Wen and Lee was analyzed in a quantitative manner. We noted that the Fermi-liquid correction factor, a2, predicted by the model could be obtained with the values around 0.5, which might correspond to prospect the mechanism of high-Tc in the underdoped case to be a single Boson condensation possibly.
48
Tsai, Cheng-Wei, and 蔡承磑. "Applying the Filter Design Approach to A Resonator Based Waveguide-To-Microstrip Transition." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/e6nu33.
Full text
49
SHIE, CHING-HENG, and 謝青航. "Dual-Mode Double-Ring Resonator for Microstrip Band-Pass Filter Design and Analysis." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/61123412212221939142.
Full textAbstract:
碩士國防大學中正理工學院
電子工程研究所
91
In this thesis, the Double-Ring filter is proposed to improve the bandwidth of conventional ring filters. The possibility of the Double-Ring filter will be verified by measurements and simulations. The mode coupling techniques of the Double-Ring resonator can be classified as two types: (1) The Directive coupled-mode, (2) The Cross coupling-mode. Both of Double-Ring filter and Extended Double-Ring filter belong to the Directive coupled-mode. By the measurements and simulations the possibility of the mode coupling techniques can be verified. By this contribution the Double-Ring filter and the Extended Double-Ring filter all have the characteristic of pass-band. In the experiment design, we can fit the filter by the techniques of adjusting values, bridging capacitance and cascade-stage, and it can be served as a reference for Double-Ring filter design. From the matching techniques, the Double-Ring filter is designed and compared with Butterworth filter, Single-Ring filter and Chebyshev filter for the advantages. The measurements and the simulations are similar.
50
Jun-De, Jin, and 金俊德. "A study of ferromagnetic resonance in T-type microstrip resonator at microwave frequency." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/91728938819352421699.
Full text