Dissertations / Theses on the topic 'Resonator frequency'
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Pourkamali, Siavash. "High frequency capacitive single crystal silicon resonators and coupled resonator systems." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/26563.
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Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2007.Committee Chair: Ayazi, Farrokh; Committee Member: Allen, Mark; Committee Member: Brand, Oliver; Committee Member: Degertekin, Levent; Committee Member: Papapolymerou, John. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Desjardins, Jason. "Reconfigurable Dielectric Resonator Antennas." Thesis, Université d'Ottawa / University of Ottawa, 2011. http://hdl.handle.net/10393/19838.
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With the increasing demand for high performance communication networks and the proliferation of mobile devices, significant advances in antenna design are essential. In recent years the rising demands of the mobile wireless communication industry have forced antennas to have increased performance while being limited to an ever decreasing footprint. Such design constraints have forced antenna designers to consider frequency agile antennas so that their behavior can adapt with changing system requirements or environmental conditions. Frequency agile antennas used for mobile handset applications must also be inexpensive, robust, and make use of electronic switching with reasonable DC power consumption.
Previous works have addressed a number of these requirements but relatively little work has been performed on frequency agile dielectric resonator antennas (DRAs). The objective of this thesis is to investigate the use of DRAs for frequency reconfigurability. DRAs are an attractive option due to their compactness, very low losses leading to high radiation efficiencies (better than 95%) and fairly wide bandwidths compared to alternatives. DRA’s are also well suited for mobile communications since they can be placed on a ground plane and are by nature low gain antennas whose radiation patterns typically resemble those of short electric or magnetic dipoles.
One way to electronically reconfigure a DRA, in the sense of altering the frequency band over which the input reflection coefficient of the antenna is below some threshold, is to partially load one face of the DRA with a conducting surface. By altering the way in which this surface connects to the groundplane on which the DRA is mounted, the DRA can be reconfigured due to changes in its mode structure. This connection was first made using several conducting tabs which resulted in a tuning range of 69% while having poor cross polarization performance. In order to address the poor cross polarization performance a second conducting surface was placed on the opposing DRA wall. This technique significantly reduced the cross polarization levels while obtaining a tuning range of 83%. The dual-wall conductively loaded DRA was then extended to include a full electronic implementation using PIN diodes and varactor diodes in order to achieve discrete and continuous tuning respectively. The two techniques both achieved discrete tuning ranges of 95% while the varactor implementation also had a continuous tuning range of 59% while both maintaining an acceptable cross polarization level.
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Chambers, James Paul. "High frequency Pound-Drever-Hall optical ring resonator sensing." Texas A&M University, 2007. http://hdl.handle.net/1969.1/85824.
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A procedure is introduced for increasing the sensitivity of measurements in
integrated ring resonators beyond what has been previously accomplished. This is
demonstrated by a high-frequency, phase sensitive lock to the ring resonators. A
prototyped fiber Fabry-Perot cavity is used for comparison of the method to a similar
cavity. The Pound-Drever-Hall (PDH) method is used as a proven, ultra-sensitive
method with the exploration of a much higher frequency modulation than has been
previously discussed to overcome comparatively low finesse of the ring resonator
cavities. The high frequency facilitates the use of the same modulation signal to
separately probe the phase information of different integrated ring resonators with
quality factors of 8.2 x10^5 and 2.4 x10^5.
The large free spectral range of small cavities and low finesse provides a
challenge to sensing and locking the long-term stability of diode lasers due to small
dynamic range and signal-to-noise ratios. These can be accommodated for by a
calculated increase in modulation frequency using the PDH approach. Further, cavity
design parameters will be shown to have a significant affect on the resolution of the
phase-sensing approach. A distributed feedback laser is locked to a ring resonator to
demonstrate the present sensitivity which can then be discussed in comparison to other
fiber and integrated sensors.
The relationship of the signal-to-noise ratio (S/N) and frequency range to the
cavity error signal will be explored with an algorithm to optimize this relationship. The
free spectral range and the cavity transfer function coefficients provide input parameters
to this relationship to determine the optimum S/N and frequency range of the respective
cavities used for locking and sensing. The purpose is to show how future contributions to the measurements and experiments of micro-cavities, specifically ring resonators, is
well-served by the PDH method with high-frequency modulation.
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Bakam, Nguenouho Odette Sandrine. "Ceramic coaxial resonator filter in a CubeSat system." Thesis, Cape Peninsula University of Technology, 2017. http://hdl.handle.net/20.500.11838/2639.
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Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2017.RF and microwave filters can be implemented using ceramic coaxial resonators. This technology has been widely employed in nanosatellite communications systems recently, owing to its large quality factor (Q), permitting them to have low loss and narrow bandwidth. Features such as high selectivity, high power handling, excellent rejection, and low passband insertion loss are just a few of the key performance areas offered by ceramic coaxial resonators. This feature makes them suitable for use in bandpass filters. Applications with demanding specifications requiring low volume and mass make use of this technology. Fulfilling the required performance goals can be challenging, given the size and weight restriction. Difficulties such as finding the correct length of resonators and the coupling capacitors’ structure to meet the size restriction, limit the type of ceramic coaxial resonators to use. This thesis presents the design of a bandpass filter using ceramic coaxial resonators, which provides evidence of the concept for F’SATI’s future needs. This design will be used in an imminent space mission and the intention is to mount the bandpass filter in the receiver communications system. An intensive investigation was conducted into the use of filters for nanosatellite communication systems. The Chebyshev LC ladder low pass prototype was used to derive the conventional bandpass filter. Thereafter, the coupled resonator bandpass filter was derived using the conventional bandpass filter topology combined with the admittance inverter. Following this, using the ceramic coaxial resonators datasheet and information provided by the manufacturers, the coupled resonator bandpass filter was converted into a 3D model for further simulations, using CST Microwave Studio®. The ceramic coaxial resonator filter fabricated using Rogers’s material provided satisfactory results at its operating frequency between 2.2 GHz and 2.3 GHz. A radiation level test was performed on the filter to justify the use of the metallic enclosure. The test presented a low level of radiation measured at the filter operating frequency (2.25 GHz). The filter was also subjected to temperature cycling.
French–South African Institute of Technology (F’SATI) National Research Foundation (NRF)
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Lennartsson, Christian. "The Frequency Dependence of the Surface Sensitivity of Resonator Biosensors." Thesis, Linköping University, The Department of Physics, Chemistry and Biology, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-9741.
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En studie i hur känsligheten avtar från ytan hos biosensorer med höga frekvenser presenteras. Med ny teknologi som avancerade elektroakustiska tunnfilms komponenter, så kallade FBARs, blir tidigare outforskade områden som decay längden möjliga att studera.
För att undersöka hur frekvenssvaret och känsligheten påverkas av interaktioner långt ut från en sensoryta används proteinkemi. Ett protokoll har optimerats innehållande aktivering med EDC/NHS och fibrinogen för att säkerställa en jämn tjocklek och fördelning av ett adsorberat proteinlager över en yta.
Dessa ytor kontrollerades först med hjälp av ellipsometri och sedan i ett QCM instrument. Alla experiment med de högfrekventa FBAR sensorerna utfördes vid Ångströmslaboratoriet i Uppsala där pågående forskning inom området finns.
Resultaten bekräftar teorin om en avtagande känslighet i och med ett ökat avstånd från ytan. En experimentell genomförd och beräknad tjocklek för decay längden uppskattades som inte helt stämde överens med den teoretiskt beräknade.
En ny term föreslås då frekvenssvaret hos en biosensor planar ut. Detta är en effekt som sker vid dubbla tjockleken av den teoretisk beräknade tjockleken av decay längden och har fått namnet; detection length. Efter denna längd eller gräns observeras en inverterad signal som det än så länge inte finns någon förklaring till.
A study of the sensitivity decrease of biosensors working at high frequencies is presented. With new technology such as film bulk acoustic resonators (FBAR), issues like the decay length is no longer irrelevant theory but may cause limitation in the system as well as it offers new detection possibilities.
To investigate the frequency response and sensitivity, layer-on-layer construction chemistry was used. A protocol involving activation with EDC/NHS and coupling chemistry with fibrinogen was optimized to ensure accurate thickness and uniformly distribution of each layer over the surface.
Surfaces were characterized using null ellipsometry and the protocol was tested in a traditional quartz crystal microbalance (QCM). Experiments with the FBAR were preformed at the Ångström laboratory in Uppsala were there is ongoing research and development in FBAR technology.
The results confirmed the theory of decreasing frequency and sensitivity further out from the surface. An experimental and estimated thickness was calculated which to some extent correlates to the theoretically calculated decay length.
A new terminology is suggested when the frequency levels off. It occurs approximately at twice the distance and thickness of the theoretically calculated decay length and is given the name; detection length. Beyond the detection length an inverted signal is observed which cannot yet be explained for.
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Djurberg, Axel, Fredrik Forsberg, Anton Lind, and Ludvig Snihs. "Wireless Power Transfer in Cavity Resonator." Thesis, Uppsala universitet, Fasta tillståndets elektronik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-444250.
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The purpose of this paper is to achieve wireless power transfer inside a resonating cavity, and thereby apply this to charge batteries. The idea is to convert radio frequency waves into direct current, which can charge the batteries. This was done by creating an LC-antenna, which in turn was connected to a rectifier. A data logger was also built, this to be able to read and log the power within the cavity to examine its power distribution. Because of COVID-19 restrictions, access to laboratory and equipment was limited. Due to this, smaller experiments where performed to make sure that all parts worked as intended before trying to perform tests inside the cavity resonator. The results were varied, some favorable, some not. However, all experiments gave insight and further understanding on the issue. The cavity operations had varied results. The data logger was able to pick up, at most, 7.6 % of the power output by the function generator. However, some problems arose with the rectifier which resulted in it not working for higher frequencies. Though, it was capable of rectifying RF signals at lower frequencies from a function generator, which was used to charge a battery. Consequently, there was no charging of batteries inside the cavity. However, three dimensional wireless power transfer was achieved. With some improvements to the current designs, the main goal could be accomplished
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Banghua, Zhou, and Huang Mingsheng. "A Dielectric Resonator Stabilized Frequency Modulation Oscillator in the S-Band." International Foundation for Telemetering, 1994. http://hdl.handle.net/10150/611725.
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International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, CaliforniaWith the development of the airborne telemetry technique, it will be demanded that the transmitting sets on the missiles are more reliable and smaller. A frequency modulation (FM) oscillator stabilized with a dielectric resonator (DR), which can operates in the S-band directly, is presented. The FM oscillator is of simple circuit, reliable operation in the stabilization, small size, light weight and low cost. It will have a certain prospect of application in the airborne telemetry transmitting sets.
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Ganesan, Adarsh. "Phononic frequency combs." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/274878.
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Optical frequency combs have resulted in significant advances in optical frequency metrology and found wide application to precise physical measurements and molecular fingerprinting. A direct analogue of frequency combs in the phononic or acoustic domain has not been reported to date. This thesis describes a series of results to provide the first clear evidence for the generation of phononic frequency combs in the domain of micromechanical resonators. These results are supported by a theoretical framework which was originally developed to predict the existence of such features of combs in physical systems described by Fermi-Pasta-Ulam dynamics. The phononic frequency combs is mediated by nonlinear coupling between a primary driven mode and one or more parametrically excited internal modes. We provide experimental evidence for the formation of such phononic frequency combs in systems comprising of 2 or more coupled modes, with results qualitatively consistent with previous numerical studies based on Fermi-Pasta-Ulam dynamics. Additionally, externally pumped comb processes are also reported. Through systematic experiments at different drive frequencies and amplitudes, we portray the well-connected processes of phononic frequency comb formation and define attributes to control their concomitant features. Further, the interplay between these new nonlinear resonances and the well-established Duffing phenomenon is also discussed. While the experimental verification of the existence of phononic frequency combs is of scientific interest, several potential engineering applications exist including the unique capability to track resonant frequency of a micromechanical resonator without the requirement for an external feedback loop to sustain oscillations at the resonant frequency. The initial experimental results also demonstrate that good short-term frequency stability may be obtained for such micromechanical resonators operated under ambient conditions.
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Wang, Zheng. "DEVELOPMENT OF ACOUSTIC MODELS FOR HIGH FREQUENCY RESONATORS FOR TURBOCHARGED IC-ENGINES." Thesis, KTH, MWL Marcus Wallenberg Laboratoriet, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-91335.
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Automotive turbo compressors generate high frequency noise in the air intake system. This sound generation is of importance for the perceived sound quality of luxury cars and may need to be controlled by the use of silencers. The silencers usually contain resonators with slits, perforates and cavities. The purpose of the work reported is to develop acoustic models for these resonators where relevant effects such as the effect of realistic mean flow on losses and possibly 3D effects are considered. An experimental campaign has been undertaken where the two-port matrices and transmission loss of four sample resonators has been measured without flow and for two different mean flow speeds (M=0.05 & M=0.1) using two source location technique. Models for the four resonators have been developed using a 1D linear acoustic code (SIDLAB) and a FEM code (COMSOL Multi-physics). Different models, from the literature, for including the effect of mean flow on the acoustic losses at slits and perforates have been discussed. Correct modeling of acoustic losses for resonators with complicated geometry is important for the simulation and development of new and improved silencers, and the present work contributes to this understanding. The measured acoustic properties compared well with the simulated model for almost all the cases.
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Brand, Tobias Gerhardus. "Synthesis methods for multi-band coupled resonator filters." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/95910.
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Thesis (PhD)--Stellenbosch University, 2014.ENGLISH ABSTRACT: In this dissertation a number of techniques to design multi-band filters, with specific focus on coupled resonator implementations, is presented. Multi-band transfer functions are constructed from single-band transfer functions using frequency mapping methods. A general class of rational mapping functions is presented that can accommodate arbitrary bandwidth specifications. Multi-band circuits are synthesised directly from multi-band transfer functions and are obtained by applying reactance transformations to single-band prototype circuits. For the direct synthesis of multi-band filters from multi-band transfer functions coupling matrix synthesis methods are employed. The circuits that result from matrix synthesis methods tend to have topologies that are undesirable from a practical perspective and must be simplified using rotations of the coupling matrix. The synthesis of multi-band filters through reactance transformations is both simple and result in filters that have practical topologies for realisation as coupled resonator circuits. Multiple filters are designed using different design methodologies and different transmission line technologies to illustrate the various design possibilities. The designs include both all-pole and cross-coupled filters and employ single-layer stripline, multi-layer stripline as well as coaxial resonators as transmission line technologies for the implementations.
AFRIKAANSE OPSOMMING: In hierdie proefskrif word verskeie ontwerpstegnieke vir multi-band filters aangebied en word daar spesifiek klem gelê op filters wat as gekoppelde resoneerder strukture geïmplimenteer kan word. Multi-band oordragsfunksies word geskep uit enkelband oordragsfunksies deur gebruik te maak van wiskundige afbeeldingstegnieke. ’n Spesiale klas van rasionale funksies word voorgestel wat spesifiek gebruik kan word om multi-band funksies te skep wat ’n arbitrêre bandwydte spesifikasie het. Multi-band stroombane word direk gesintetiseer vanuit multi-band oordragsfunksies en word ook verkry deur die toepassing van reaktansietransformasies op enkelband stroombane. Vir die direkte sintese van multi-band stroombane vanuit multi-band oordragsfunksies word stroombane gesintetiseer as koppelmatrikse. Stroombane wat op hierdie wyse gesintetiseer word is geneig om topologieë te hê wat nie baie gesog is vanuit ’n praktiese perspektief nie en matriks rotasies word dan hier ingespan om die stroombane se topologieë te vereenvoudig. Die sintese van multi-band stroombane deur gebruik te maak van reaktansietransformasies is beide eenvoudig en lei tot stroombane wat praktiese topologieë het vir implimentering as gekoppelde resoneerder strukture. Die ontwerpsmoontlikhede wat die verskillende metodieke bied word geïllustreer deur die ontwerp van verskeie filters op verskillende maniere waar daar gebruik gemaak word van verskeie transmissielyn tegnologië. Die filter ontwerpe sluit filters in waar alle transmissienulle by oneidige frekwensies is, sowel as gevalle waar somige transmissienulle by eindige frekwensies is. Die filters word geïmplimenteer deur gebruik te maak van koaksiale resoneerders sowel as enkellaag en multilaag strooklyn.
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McIntyre, Dustin L. "The coaxial cavity resonator as a prototype RF IC engine ignition source." Morgantown, W. Va. : [West Virginia University Libraries], 2000. http://etd.wvu.edu/templates/showETD.cfm?recnum=1504.
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Thesis (M.S.)--West Virginia University, 2000.Title from document title page. Document formatted into pages; contains xii, 119 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 106-107).
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Xu, Changting. "Investigation of Modulation Methods to Synthesize High Performance Resonator-Based RF MEMS Components." Research Showcase @ CMU, 2018. http://repository.cmu.edu/dissertations/1135.
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The growing demand for wireless communication systems is driving the integration of radio frequency (RF) front-ends on the same chip with multi-band functionality and higher spectral efficiency. Microelectromechanical systems (MEMS) have an overarching applicability to RF communications and are critical components in facilitating this integration process. Among a variety of RF MEMS devices, piezoelectric MEMS resonators have sparked significant research and commercial interest for use in oscillators, filters, and duplexers. Compared to their bulky quartz crystal and surface acoustic wave (SAW) counterparts, MEMS resonators exhibit impressive advantages of compact size, lower production cost, lower power consumption, and higher level of integration with CMOS fabrication processes. One of the promising piezoelectric MEMS resonator technologies is the aluminum nitride (AlN) contour mode resonator (CMR). On one hand, AlN is chemically stable and offers superior acoustic properties such as large stiffness and low loss. Furthermore, CMRs offer low motional resistance over a broad range of frequencies (few MHZ to GHz), which are lithographically-definable on the same silicon substrates. To date, RF MEMS resonators (include CMRs) have been extensively studied; however, one aspect that was not thoroughly investigated is how to modulate/tune their equivalent parameters to enhance their performance in oscillators and duplexers. The goal of this thesis is to investigate various modulation methods to improve the thermal stability of the resonator, its “effective” quality factor when used in an oscillator, and build completely novel non-reciprocal components. Broadly defined, modulation refers to the exertion of a modifying or controlling influence on something, herein specifically, the resonator admittance. In this thesis, three categories of modulation methods are investigated: thermal modulation, force modulation, and external electronic modulation. Firstly, the AlN CMR’s center frequency can be tunned by the applied thermal power to the resonator body. The resonator temperature is kept constant (for example, 90 °C) via a temperature sensor and feedback control such that the center frequency is stable over the whole operation temperature range of interest (e.g. –35 to 85 °C). The maximum power consumption to sustain the maximum temperature difference (120 ºC in this thesis) between resonator and ambient is reduced to a value as low as 353 μW – the lowest ever reported for any MEMS device. These results were attained while simultaneously maintaining a high quality factor (up to 4450 at 220 MHz device). The feedback control was implemented by either analog circuits or via a microprocessor. The analog feedback control, which innovatively utilized a dummy resistor to compensate for temperature gradients, resulted in a total power consumption of 3.8 mW and a frequency stability of 100 ppm over 120 ºC. As for the digital compensation, artificial neural network algorithm was employed to facilitate faster calibration of look-up tables for multiple frequencies. This method attained a frequency stability of 14 ppm over 120 ºC. The second modulation method explored in this thesis is based on the use of an effective external force to enhance the 3-dB quality factor of AlN CMRs and improve the phase noise performance of resonator-based oscillators. The force modulation method was embodied in a two-port device, where one of the two ports is used as a one-port resonator and the other is driven by an external signal to effectively apply an external force to the first port. Through this technique, the quality factor of the resonator was boosted by 140 times (up to 150,000) and the phase noise of the corresponding oscillator realized using the resonator was reduced by 10 dBc/Hz. Lastly, a novel magnetic-free electrical circulator topology that facilitates the development of in-band full duplexers (IBFD) for simultaneous transmit and receive (STAR) is proposed and modeled. Fundamentally, a linear time-invariant (LTI) filter network parametrically modulated via a switching matrix is used to break the reciprocity of the filter. The developed model accurately predicts the circulator behavior and shows very good agreement with the experimental results for a 21.4 MHz circulators built with MiniCircuit filter and switch components. Furthermore, a high frequency (1.1 GHz) circulator was synthesized based on AlN MEMS bandpass filters and CMOS RF switches, hence showing a compact approach that can be used in handheld devices. The modulation frequency and duty cycle are optimized so that the circulator can provide up to 15 dB of isolation over the filter bandwidth while good power transfer between the other two ports is maintained. The demonstrated device is expected to intrinsically offer low noise and high linearity. The combination of the first two modulation methods facilitates the implementation of monolithic, temperature-stable, ultra-low noise, multi-frequency oscillator banks. The third modulation technique that was investigated sets the path for the development of CMOS-compatible in-band full duplexers for simultaneous transmit and receive and thus facilitates the efficient utilization of the electromagnetic spectrum. With the aid of all these three modulation approaches, the author believes that a fully integrated, multi-frequency, spectrum-efficient transceiver is enabled for next-generation wireless communications.
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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.
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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.
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Whitehead, Neil. "Static and rotational non contact torque measurement utilising a mechanical resonator providing a frequency output." Thesis, Brunel University, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.367860.
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Lewis, A. P. "The determination of the fundamental resonant frequency of a substrate-mounted open cylindrical dielectric resonator." Thesis, University of Bath, 1986. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370989.
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Stefan, Anca Irina. "Modeling and design of resonators for electron paramagnetic resonance imaging and ultra high field magnetic resonance imaging." Columbus, Ohio : Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1133293403.
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Walls, Tom. "The application of a Fabry-Perot resonator to the design of a low noise microwave frequency source." Thesis, Heriot-Watt University, 1993. http://hdl.handle.net/10399/1959.
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Subramanian, Ajay. "A LOW PHASE NOISE K-BAND OSCILLATOR UTILIZING AN EMBEDDED DIELECTRIC RESONATOR ON MULTILAYER HIGH FREQUENCY LAMINATES." Master's thesis, University of Central Florida, 2008. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/2357.
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K-Band (18 to 26 GHz) dielectric resonator oscillators are typically used as a local oscillator in most K-Band digital transmitter/receiver topologies. Traditionally, the oscillator itself is made up of an active device, a dielectric resonator termination network, and a passive load matching network. The termination network embodies a cylindrical high permittivity dielectric resonator that is coupled on the same plane as a current carrying transmission line. This configuration provides an adequate resonance needed for oscillation but has some limitations. In order to provide a high Q resonance the entire oscillator is placed in a metal box to prevent radiation losses. This increases the overall size of the device and makes it difficult to integrate in smaller transceiver topologies. Secondly, a tuning screw is required to help excite the dominant mode of the resonator to achieve the high Q response. This can cause problems in precision due to the mechanical jitter of the screw inherent in mobile devices. By embedding this resonator inside the substrate it is possible to realize a very high Q resonance at a desired frequency and remove the need for a metal cavity and tuning screw. An additional advantage can be seen in terms of overall size reduction of the oscillator circuit. To demonstrate the feasibility of utilizing a dielectric resonator embedded within a substrate, a K-Band oscillator proof of concept has been designed, fabricated, and tested. The oscillator is comprised of a low noise active transistor device, an embedded k-band dielectric resonator and a passive transmission line load network. All elements within the oscillator are optimized to produce a steady oscillation near 20 GHz. Preliminary investigations of a microstrip resonator S-band (2-3 GHz) oscillator are first discussed. Secondly, various challenges in design and fabrication are discussed. Thereafter, simulated and measured results of the embedded DRO structure are presented. Emphasis is placed on output oscillation power and low phase noise. With further development, the entire oscillator can be embedded within the substrate leaving only the active device on the surface. This allows for a considerable reduction in material cost and simple integration with miniaturized digital transmitter/receiver devices.M.S.E.E.
School of Electrical Engineering and Computer Science
Engineering and Computer Science
Electrical Engineering MSEE
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Maxey, Christopher Allen. "Switched-Tank VCO Designs and Single Crystal Silicon Contour-Mode Disk Resonators for use in Multiband Radio Frequency Sources." Thesis, Virginia Tech, 2004. http://hdl.handle.net/10919/10074.
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To support the large growth in wireless devices, such as personal data assistants (PDAs), wireless local area network (WLAN) enabled laptop computers, and intelligent transportation systems (ITS), the FCC allocated three high-frequency bands for unlicensed operation. Of particular interest is the 5-6 GHz Unlicensed National Information Infrastructure (UNII) band intended to support high-speed WLAN applications. The UNII band is further split into three smaller 100 MHz sub-bands: 5.15 - 5.25 GHz; 5.25-5.35 GHz; and 5.725-5.825 GHz.
VCOs that can be switched between each of the three UNII sub-bands offer flexibility and optimum phase-locked loop (PLL) design versus non-switchable VCOs. This work presents switched-tank voltage controlled oscillators (VCOs) designed in Motorolaà Âs 0.18 à µm HIP6WRF BiCMOS process that could be used in multiband receivers covering the three UNII sub-bands. The first VCO was optimized for low power consumption. The VCO draws a total of 6.75 mA from a 1.8 V supply including buffer amplifiers. The VCO is designed with a switched-capacitor LC tank circuit that can switch to two center frequencies, 5.25 GHz and 5.775 GHz, with 200 MHz of varactor-supplied tuning range. The simulated output voltage swing is 2.0 V peak-to-peak and is kept constant between sub-bands by an active PMOS load integrated into the biasing circuitry. The second VCO was optimized for a high output voltage swing by replacing the current biasing circuit with a degenerating inductor. This design targeted three center frequencies, 5.2 GHz, 5.3 GHz, and 5.775 GHz, with 100 MHz of tuning range. This design has an output peak-to-peak voltage swing of 5.2 V but consumes an average of 16.5 mA from a 1.8 V supply. The two fabricated circuits exhibit tuning ranges similar to the simulated results; however, the center frequencies of each decrease due to interconnect parasitics there were unaccounted for in the designs. The measured center frequencies are 4.4 GHz and 5.37 GHz for the first design, and 4.4 GHz and 4.7 GHz for the second design (with one state inoperative due to a faulty switch).
The phase noise of the fabricated VCO designs was limited primarily by the low quality factor (Q-factor) of the on-chip LC tank circuits. Oscillators referenced with high-Q off-chip components such as quartz crystal references and surface acoustic wave (SAW) resonators in a PLL can exhibit much improved performance; however, these off-chip components add packaging/assembly cost and higher bill of materials, impedance matching issues, and parasitics that can significantly affect performance for RF applications. Thus, there is tremendous incentive for integrating high-Q components on-chip with the eventual goal of consolidating all of the RF/analog/digital components onto a single wireless-enabled chip, commonly called RF system-on-a-chip (SoC).
Microelectromechanical (MEM) resonators have received significant attention based on their ability to provide high on-chip Q-factors at RF frequencies using fabrication techniques that are compatible with modern IC processes. MEM resonators transduce electrical signals into extremely low-loss mechanical vibration and vice versa. Consequently, this thesis also describes the modeling, simulation, and fabrication of contour-mode disk-shaped MEM resonators. This resonator geometry is capable of providing high-Q oscillation at frequencies exceeding 1 GHz at sizes easily within the limits of modern photolithography techniques. Finite element analysis is used to predict the frequency response of disk resonators under various operating conditions and to determine variables that are most critical to the resonator design. A silicon-on-insulator (SOI) fabrication process for constructing the disk is also discussed. Finally, the possible future integration of MEM resonators with multiband VCOs in a common IC process is proposed.Master of Science
20
Munyai, Pandelani Reuben Mulalo. "On the improvement of phase noise in wideband frequency synthesizers." Diss., University of Pretoria, 2017. http://hdl.handle.net/2263/63003.
Full textAbstract:
Wireless communication systems are based on frequency synthesizers that generate carrier signals,
which are used to transmit information. Frequency synthesizers use voltage controlled oscillators
(VCO) to produce the required frequencies within a specified period of time. In the process of generating
frequency, the VCO and other electronic components such as amplifiers produce some unwanted
short-term frequency variations, which cause frequency instability within the frequency of
interest known as phase noise (PN). PN has a negative impact on the performance of the overall wireless
communication system. A literature study conducted on this research reveals that the existing PN
cancellation techniques have some limitations and drawbacks that require further attention.
A new PN correction technique based on the combination of least mean square (LMS) adaptive filtering
and single-loop single-bit Sigma Delta (SD) modulator is proposed. The new design is also based
on the Cascaded Resonator Feedback (CRFB) architecture. The noise transfer function (NTF) of the
architecture was formulated in way that made it possible to stabilize the frequency fluctuations within
the in-band (frequency of interest) by locating its poles and zeros within the unit circle.
The new design was simulated and tested on a commercially available software tool called Agilent Advanced Design System (ADS). Simulation results show that the new technique achieves better
results when compared with existing techniques as it achieves a 104 dB signal-to-noise (SNR), which
is an improvement of 9 dB when compared with the existing technique accessed from the latest
publications. The new design also achieves a clean signal with minimal spurious tones within the inband
with a phase noise level of -141 dBc/Hz (lower phase noise level by 28 dBc/Hz) when compared
with the existing techniques.Thesis (MEng)--University of Pretoria, 2017.
Electrical, Electronic and Computer Engineering
MEng
Unrestricted
21
Maricar, Mohamed Ismaeel. "Design of circuits to enhance the performace of high frequency planar Gunn diodes." Thesis, De Montfort University, 2014. http://hdl.handle.net/2086/10858.
Full textAbstract:
The project contains adventurous research, with an aim to understand and design a planar Gunn diode with a novel integrated circuit configuration to extract the 2nd harmonic. This will potentially enhance the Gunn diode as a high frequency source towards frequencies in excess of 600 GHz. The RF performance from the above integrated circuit was achieved by design and simulation of radial and diamond stub resonators, which were used to short the fundamental oscillation frequency while allowing the second harmonic frequency to pass through to the load. The diamond stub resonator is a new configuration offering a number of advantages which include a higher loaded quality factor and occupies 55% less chip area than a comparable radial stub resonator. The designed novel circuits with integrated planar Gunn diode were fabricated using microwave monolithic integrated circuits (MMIC) technology at the James Watt Nanofabrication centre in Glasgow University. Full DC and microwave characterisation of the diodes and integrated circuits with diodes was carried out using a semiconductor analyser, network analyser (10 MHz to 110GHz) and spectrum analyser (10 MHz to 125GHz). The microwave measurements were carried out at the high frequency RF laboratories in Glasgow University. Both GaAs and InP based Gunn diodes were characterised and RF characterisation work showed that higher fundamental frequencies could be obtained from Gunn diodes fabricated on InGaAs on a lattice matched InP substrate. Planar Gunn diodes with an anode to cathode spacing of 4 microns giving a fundamental frequency of oscillation of 60 GHz were fabricated as an integrated circuit with coplanar waveguide (CPW) circuit elements to extract the second harmonic. A second harmonic frequency of 120 GHz with an RF output power of -14.11 dBm was extracted with very good fundamental frequency suppression. To the authors knowledge this was the first time second harmonic frequencies have been extracted from a planar Gunn diode technology. Aluminium gallium arsenide (AlGaAs) planar Gunn diodes were also designed with an integrated series inductor to match the diode at the fundamental frequency to obtain higher RF output powers. Devices with a 1 micron anode to cathode separation gave the highest fundamental oscillation frequency of 121 GHz the highest reported for a GaAs based Gunn diode and with an RF output power of -9 dBm. These circuits will have potential applications in secure communications, terahertz imaging etc.
22
Yasar, Orten Pinar. "Numerical Analysis, Design And Two Port Equivalent Circuit Models For Split Ring Resonator Arrays." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12611620/index.pdf.
Full textAbstract:
Split ring resonator (SRR) is a metamaterial structure which displays negative permeability values over a relatively small bandwidth around its magnetic resonance frequency. Unit SRR cells and arrays have been used in various novel applications including the design of miniaturized microwave devices and antennas. When the SRR arrays are combined with the arrays of conducting wires, left handed materials can be constructed with the unusual property of having negative valued effective refractive indices.
In this thesis, unit cells and arrays of single-ring multiple-split type SRR structures are numerically analyzed by using Ansoft&rsquos HFSS software that is based on the finite elements method (FEM). Some of these structures are constructed over low-loss dielectric substrates and their complex scattering parameters are measured to verify the numerical simulation results. The major purpose of this study has been to establish equivalent circuit models to estimate the behavior of SRR structures in a simple and computationally efficient manner. For this purpose, individual single ring SRR cells with multiple splits are modeled by appropriate two-port RLC resonant circuits paying special attention to conductor and dielectric loss effects. Results obtained from these models are compared with the results of HFSS simulations which use either PEC/PMC (perfect electric conductor/perfect magnetic conductor) type or perfectly matched layer (PML) type boundary conditions. Interactions between the elements of SRR arrays such as the mutual inductance and capacitance effects as well as additional dielectric losses are also modeled by proper two-port equivalent circuits to describe the overall array behavior and to compute the associated transmission spectrum by simple MATLAB codes. Results of numerical HFSS simulations, equivalent circuit model computations and measurements are shown to be in good agreement.
23
Khan, Md Mahfujul H. "Understanding Impact Load Wave Transmission Performance of Elastic Metamaterials." University of Akron / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=akron1479146177020136.
Full text
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Guillot, Pierre. "Contribution à l’étude des architectures de radiocommunications à références d’horloges hautes fréquences : application des résonateurs BAW à la génération de fréquence de référence dans les systèmes de communication mobile." Thesis, Paris Est, 2011. http://www.theses.fr/2011PEST1025/document.
Full textAbstract:
Ces travaux de thèse portent principalement sur la génération de signal d'horloge haute fréquence. Dans un premier temps, la faisabilité d'un oscillateur à base de BAW y est démontrée par la conception d'un circuit en technologie CMOS 65 nm. Les deux principales innovations sont les performances en terme de stabilité (bruit de phase de -128dBc/Hz à 100kHz de la porteuse) et en précision (implémentation d'une banque de capacités ayant un pas de 0.4ppm) de l'oscillateur. Sa consommation est optimisée (0.9mW). Il est suivi d'un diviseur faible bruit (-140dBc/Hz à 100kHz de la porteuse) délivrant un signal à 500MHz. Dans un second temps, les imperfections des résonateurs BAW sont analysées. Une procédure de calibration comprenant une calibration initiale et une calibration en boucle ouverte est alors proposée. Cette dernière repose sur l'identification et l'utilisation d'un modèle comportemental du dispositif, régulièrement mis à jour grâce à un filtre de Kalman. Une précision de 0.4 ppm est atteinteThis thesis deals with the gigahertz range reference frequency generation. In a first part, this document presents the design of a 500 MHz oscillator in a 65 nm CMOS process using a 2 GHz Bulk Acoustic Wave resonator. A digital frequency control is implemented using a switched capacitor bank in parallel to the resonator. The tuning range is up to 500 kHz with a minimum step of 200 Hz. The oscillator core uses a differential topology and is designed for low phase noise (-128 dBc/Hz at 100 kHz offset) at low power consumption (0.9 mW). It is followed by a low noise divider which provides a 500 MHz output with a phase noise of -139 dBc/Hz at 100 kHz offset from the carrier. In a second part, we consider a method for the calibration of a BAW based frequency reference. In fact, the frequency variations of a BAW oscillator against process, supply, temperature and aging effects make difficult its use as a frequency reference. We propose here a method based on Kalman filtering to identify with high precision a behavioral model of this BAW reference, thus enabling its use in an open loop frequency tuning. A precision of 0.4 ppm is achieved
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Knuth, Thomas. "Auslegung, Entwicklung und Inbetriebnahme eines longitudinalen und transversalen Feedbacksystems zur Dämpfung gekoppelter Teilchenpaket-Instabilitäten im BESSY-II-Speicherring." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2000. http://dx.doi.org/10.18452/14601.
Full textAbstract:
Das Auftreten kohärenter Schwingungen gekoppelter Teilchenpakete führt in modernen Elektronenspeicherringanlagen zu einer wesentlichen Beeinträchtigung ihrer Leistungsfähigkeit als Synchrotronstrahlungsquelle. Diese Instabilitäten können in longitudinaler und transversaler Richtung auftreten und führen neben der Verminderung der Brillanz des Synchrotronlichts im ungünstigsten Fall zum Strahlverlust. Das wirkungsvollste Instrument zur Beherrschung der Instabilitäten ist ein Rückkoppelsystem (Feedbacksystem), welches die angeregten Schwingungsamplituden detektiert und dämpft. Diese Arbeit beschäftigt sich mit der Auslegung, der Entwicklung und der Inbetriebnahme zweier von ihrem Aufbau her völlig unterschiedlicher Systeme zur Korrektur von longitudinalen Synchrotronschwingungen und transversalen Betatronschwingungen. Dabei schließt das transversale Feedbacksystem sowohl die horizontale als auch die vertikale Strahlachse ein. Beide Systeme beschränken sich nicht auf die Dämpfung bestimmter Schwingungsmoden, sondern sind so ausgelegt worden, daß alle Teilchenpakete unabhängig voneinander stabilisiert werden. Innerhalb von zwei Jahren konnten alle relevanten Komponenten entwickelt, gebaut und in Betrieb genommen werden. Im Rahmen dieser Arbeit wird auf den Aufbau und die Funktionsweise wichtiger Systembausteine eingegangen und der Prozeß der Inbetriebnahme der Feedbacksysteme erläutert. Meßresultate belegen die Effizienz beider Systeme, die im Nutzerbetrieb kontinuierlich zur Dämpfung von Instabilitäten bei Strömen bis zu 220 mA eingesetzt werden. Der durch die Inbetriebnahme der Rückkoppelsysteme gewonnene Nutzen für die Experimentatoren konnte im Rahmen dieser Arbeit nachgewiesen werden. Damit verfügt BESSY-II über leistungsfähige Feedbacksysteme, die kohärente Schwingungen aller Phasenraumkoordinaten dämpfen und damit die Anforderungen an die Quellgröße einer Synchrotronstrahlungsquelle der 3. Generation gewährleisten.The appearance of coherent coupled bunch oscillations in modern electron storage rings contributes to a significant reduction of the performance as a synchrotron light source. These instabilities occur in longitudinal as well as in transversal directions and lead to a reduction of brilliance and in the worst case to beam loss. The most effective tool for controlling the instabilities is a feedback system, which detects and damps the excited oscillation amplitudes. This thesis describes the development, installation and commissioning of two completely different systems for damping of longitudinal synchrotron oscillations and transversal betatron oscillations. The transverse feedback system incorporates the horizontal as well as the vertical beam direction. Both systems are not restricted to damping certain modes of oscillation, but have been designed for the independent stabilization of all bunches separately. All components have been designed, built and commissioned within two years. In the scope of this thesis the development and the functionality of important components will be explained and the process of commissioning will be described. Measurements emphasize the efficiency of both systems, which are being used continuously for damping instabilities during user operation up to currents of 220 mA. In the scope of this thesis the improved experimental conditions for the user of the synchrotron light could be shown. Consequently, BESSY II possesses two efficient feedback systems which damp coherent oscillations of all phase space coordinates and guarantee the requirements to the source size of a 3rd generation light source.
26
He, Shujian. "A TRANSFER MATRIX APPROACH TO DETERMINE THE LOW FREQUENCY INSERTION LOSS OF ENCLOSURES INCLUDING APPLICATIONS." UKnowledge, 2017. https://uknowledge.uky.edu/me_etds/104.
Full textAbstract:
Partial enclosures are commonly used to reduce machinery noise. However, it is well known in industry that enclosures sometimes amplify the sound at low frequencies due to strong acoustic resonances compromising the performance. These noise issues are preventable if predicted prior to prototyping and production. Though boundary and finite element approaches can be used to accurately predict partial enclosure insertion loss, modifications to the model require time for remeshing and solving. In this work, partial enclosure performance at low frequencies is simulated using a plane wave transfer matrix approach. Models can be constructed and the effect of design modifications can be predicted rapidly. Results are compared to finite element analysis and measurement with good agreement. The approach is then used to design and place resonators into a sample enclosure. Improvements in enclosure performance are predicted using plane wave simulation, compared with acoustic finite element analysis, and then validated via measurement.
27
Cabras, Flaminia. "Forests as a natural seismic metabarrier: analysis of interaction between trees and Rayleigh waves." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2018. http://amslaurea.unibo.it/15200/.
Full textAbstract:
The present thesis describes a sensitivity analysis over design parameters carried out through finite element simulations on seismic metamaterials, locally resonant structures able to affect the propagation of waves passing through them. Locally resonant metamaterials represent a particular type of resonant scattering, which is very powerful mean for stopping (bandgaps) and redirecting elastic waves at different length scales.
This work, carried out at the Imperial College London, is inserted as part of the the METAFORET project, a large-scale wave experiment, which aims to demonstrate the effectiveness of
metamaterials in geophysics. In particular, this project proved that a dense forest of tree can behave as a natural seismic metamaterial for Rayleigh surface waves. Thus creating anomalous dispersion curves and bandgap, frequency regions where the wave propagation is forbidden. These regions are associated with compressional and flexural resonances of the trees.
Therefore I studied the same phenomena with time-domain numerical simulations, implemented in MATLAB. In particular, the simulation is performed with the spectral element method, a popular and efficient formulation of the finite element method that provides a numerical solution of partial differential equations. I analyzed the interaction between seismic metamaterials and the Rayleigh waves in one-dimensional and two-dimensional domain, neglecting the horizontal component to maintain the physical and numerical complexity low. This method is really efficient to conduct a sensitivity analysis, in order to identify which parameters influence the behavior of metamaterials and drive benchmarks.
28
Zeighami, Farhad. "Sub-wavelength resonators as seismic Rayleigh waves shield." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016.
Find full textAbstract:
We explore the thesis that tall structures can be protected by means of seismic metamaterials. Seismic metamaterials can be built as some elements are created over soil layer with different shapes, dimensions, patterns and from different materials. Resonances in these elements are acting as locally resonant metamaterials for Rayleigh surface waves in the geophysics context. Analytically we proved that if we put infinite chain of SDOF resonator over the soil layer as an elastic, homogeneous and isotropic material, vertical component of Rayleigh wave, longitudinal resonance of oscillators will couple with each other, they would create a Rayleigh bandgap frequency, and wave will experience attenuation before it reaches the structure.
As it is impossible to use infinite chain of resonators over soil layer, we considered finite number of resonators throughout our simulations. Analytical work is interpreted using finite element simulations that demonstrates the observed attenuation is due to bandgaps when oscillators are arranged at sub-wavelength scale with respect to the incident Rayleigh wave. For wavelength less than 5 meters, the resulting bandgaps are remarkably large and strongly attenuating when impedance of oscillators matches impedance of soil. Since longitudinal resonance of SDOF resonator are proportional to its length inversely, a formed array of resonators that attenuates Rayleigh waves at frequency ≤10 Hz could be designed starting from vertical pillars coupled to the ground. Optimum number of vertical pillars and their interval spacing called effective area of resonators are investigated. For 10 pillars with effective area of 1 meter and resonance frequency of 4.9 Hz, bandgap frequency causes attenuation and a sinusoidal impulsive force illustrate wave steering down phenomena. Simulation results proved analytical findings of this work.
29
Miri, Lavasani Seyed Hossein. "Design and phase-noise modeling of temperature-compensated high frequency MEMS-CMOS reference oscillators." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/41096.
Full textAbstract:
Frequency reference oscillator is a critical component of modern radio transceivers. Currently, most reference oscillators are based on low-frequency quartz crystals that are inherently bulky and incompatible with standard micro-fabrication processes. Moreover, their frequency limitation (<200MHz) requires large up-conversion ratio in multigigahertz frequency synthesizers, which in turn, degrades the phase-noise. Recent advances in MEMS technology have made realization of high-frequency on-chip low phase-noise MEMS oscillators possible.
Although significant research has been directed toward replacing quartz crystal oscillators with integrated micromechanical oscillators, their phase-noise performance is not well modeled. In addition, little attention has been paid to developing electronic frequency tuning techniques to compensate for temperature/process variation and improve the absolute frequency accuracy.
The objective of this dissertation was to realize high-frequency temperature-compensated high-frequency (>100MHz) micromechanical oscillators and study their phase-noise performance. To this end, low-power low-noise CMOS transimpedance amplifiers (TIA) that employ novel gain and bandwidth enhancement techniques are interfaced with high frequency (>100MHz) micromechanical resonators. The oscillation frequency is varied by a tuning network that uses frequency tuning enhancement techniques to increase the tuning range with minimal effect on the phase-noise performance. Taking advantage of extended frequency tuning range, and on-chip temperature-compensation circuitry is embedded with the sustaining circuitry to electronically temperature-compensate the oscillator. Finally, detailed study of the phase-noise in micromechanical oscillators is performed and analytical phase-noise models are derived.
30
Döringshoff, Klaus. "Optical frequency references based on hyperfine transitions in molecular iodine." Doctoral thesis, Humboldt-Universität zu Berlin, 2018. http://dx.doi.org/10.18452/19156.
Full textAbstract:
Diese Arbeit beschäftigt sich mit der Entwicklung und Untersuchung von optischen Absolutfrequenzreferenzen basierend auf rovibronischen Übergängen in molekularen Jod. Dabei werden Methoden der Doppler-freien Sättigungsspektroskopie angewendet, um einzelne Übergänge der Hyperfeinstruktur mit Linienbreiten unterhalb von 1 MHz im B-X System von molekularem Iod bei 532 nm, der zweiten harmonischen des Nd:YAG-Laser, aufzulösen. Elektronische Regelungstechniken ermöglichen eine präzise Stabilisierung der optischen Frequenz auf die Linienmitte der Übergänge mit einer Auflösung von Teilen in 10^5.
Mit dem Ziel einer weltraumtauglichen Absolutfrequenzreferenz für zukünftige Weltraummissionen, wurden zwei Spektroskopiemodule konzipiert und in quasi-monolithischen Glaskeramik-Aufbauten, als sogenanntes elegant breadboard model und engineering model, realisiert. Diese Jodfrequenzreferenzen wurden im Detail in Bezug auf ihre Frequenzstabilität und Reproduzierbarkeit untersucht und Letzteres wurde für die angestrebte Weltraumqualifizierung ersten Umwelttests, sowohl vibrations- als auch thermischen Belastungstests, unterzogen.
Für die Untersuchung der Frequenzstabilität dieser Jodreferenzen wurde ein auf einen optischen Resonator hoher Güte stabilisiertes Lasersystem für direkte Frequenzvergleiche bei 1064 nm realisiert. Die Analyse der Frequenzstabilität der Jod Referenzen zeigt eine Frequenzstabilität von 6x10^−15 bei 1 s, und weniger als 2x10^−15 bei 100 s Integrationszeit, was der bis heute besten veröffentlichten Frequenzstabilität entspricht die mit Jod Referenzen erreicht wurde.
Mit der erreichten Frequenzstabilität ermöglichen diese Absolutfrequenzreferenzen präzise Lasersysteme für zukünftige Weltraummissionen wie z.B. zur Detektion von Gravitationswellen, zur Vermessung des Gravitationsfelds der Erde oder für Präzisionstest fundamentaler Theorien der Physik.This thesis deals with the development and investigation of optical absolute frequency references based on rovibronic transitions in molecular iodine. Doppler-free saturation spectroscopy methods are employed to resolve individual transitions of the hyperfine structure with linewidths below 1 MHz in the B-X system of molecular iodine at 532 nm with the second harmonic of Nd:YAG lasers. Electronic feedback control systems are employed for laser frequency stabilization to the line center of the optical transitions with a line splitting of 10^5. With the goal of a space qualified optical absolute frequency reference for future laser-interferometric space missions, two spectroscopy setups were designed and realized in quasi-monolithic, glass-ceramic setups as so called elegant bread board model and engineering model. These iodine references were characterized in detail with respect to their frequency stability and reproducibility and the engineering model was subject to environmental tests, including vibrations and thermal cycling to verify its applicability in future space missions. For the investigation of the frequency instability of these iodine references, a frequency stabilized laser system was realized based on a temperature controlled high Finesse ULE cavity for direct frequency comparisons at 1064 nm. Analysis of the frequency stability of the iodine references revealed exceptionally low fractional frequency instability of 6x10^−15 at 1 s, averaging down to less than 2×10^−15 at 100 s integration time, constituting the best reported stability achieved with iodine references to date. With the demonstrated performance, these absolute frequency references enable precision laser systems required for future space missions that are dedicated to, e.g., the detection of gravitational waves, mapping of the Earth’s gravitational field or precision test of fundamental physics.
31
Lukacs, Mathew Walter. "Wirelessly sensing resonate frequency of passive resonators with different Q values." Master's thesis, University of Central Florida, 2011. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4970.
Full textAbstract:
Numerous techniques exist for measuring temperature using passive devices such as SAW filters. However, SAW filters have a significant limitation regarding high temperature environments exceeding 1000??C. There are several applications for a high temperature sensor in this range, most notably heat flux or temperature in turbine engines. For these environments, an alternative to SAW filters is to use a passive resonator. The resonate frequency will vary depending on the environment temperature. Understanding how the frequency changes with temperature will allow us to determine the environmental temperature. In order for this approach to work, it is necessary to induce resonance in the device and measure the resonance frequency. However, the extreme high temperature makes wired connections impractical, therefore wireless interrogation is necessary. To be practical a system of wireless interrogation of up to 20cm is desired.ID: 029809938; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Thesis (M.S.E.E.)--University of Central Florida, 2011.; Includes bibliographical references (p. 80-81).
M.S.E.E.
Masters
Electrical Engineering and Computer Science
Engineering and Computer Science
Electrical Engineering
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Laurent, Ludovic. "Nano systèmes électromécaniques résonants à haute fréquence (NEMS HF) : une rupture technologique pour l'imagerie infrarouge non refroidi." Thesis, Université Grenoble Alpes (ComUE), 2017. http://www.theses.fr/2017GREAY050/document.
Full textAbstract:
Les progrès de la microélectronique, axés en premier lieu sur l’amélioration des performances et la réduction des coûts des processeurs et des mémoires, ont aussi bénéficié depuis de nombreuses années aux capteurs, à l’éclairage, aux actionneurs et autres technologies dites More than Moore. La détection infrarouge à l’aide de détecteurs thermiques fait partie de ces bénéficiaires. Les détecteurs thermiques actuels utilisent principalement une fine couche résistive (typiquement du dioxyde de vanadium ou du silicium amorphe) déposée sur une membrane suspendue comme thermomètre : ce sont les microbolomètres. Cette technique a permis de produire des caméras thermiques dont le coût de fabrication a drastiquement chuté avec des performances qui se rapprochent des détecteurs photoniques onéreux, fonctionnant à des températures cryogéniques. Néanmoins, le coût de ces imageurs reste encore excessif pour des applications grand public (conduite nocturne, smartphones, domotique) tandis que les applications militaires (surveillance, lunettes portatives) demandent des performances accrues dans un budget maîtrisé. Un des objectifs des industriels du domaine est donc de réduire la surface des détecteurs, le pas pixel, afin d’augmenter le nombre de rétines fabriquées sur une plaque de silicium. Néanmoins, la réduction de cette surface diminue de facto le flux infrarouge incident sur le pixel, et donc le signal. Il faut donc améliorer la sensibilité des détecteurs à chaque nouveau pas pixel. La technologie résistive, largement employée par l’industrie jusqu’à maintenant, se prêtait volontiers à cet exercice jusqu’au pas de 17 µm, permettant de densifier d’un facteur 4 le nombre de détecteurs tous les 5 ans. L’auto-échauffement lié à la lecture résistive et le bruit en 1/f sont les principales causes du ralentissement observé dans cette réduction des échelles ces dernières années. Nos travaux se sont focalisés sur un nouveau principe de détection au pas de 12 µm, fonctionnant avec un auto-échauffement minime. Dans cette approche, une planche suspendue est mise en résonance mécanique autour de deux bras ancrés subissant une torsion. L’actionnement et la détection électrostatique du mouvement de la membrane sont réalisés avec deux électrodes situés 2 µm sous la planche. La modification du module d’Young avec la température et les contraintes thermiques vont modifier la fréquence de résonance. Les résonateurs mécaniques étant peu bruités, le suivi cette fréquence de résonance doit permettre de réaliser des détecteurs thermiques performants. Le travail de thèse a consisté à concevoir, fabriquer et caractériser de tels pixels et à comparer cette technique aux détecteurs résistifs. Différents modèles (linéaire et nonlinéaire) du mouvement de la structure sont présentés et comparés aux caractérisations expérimentales de résonateurs fabriqués en réseaux denses, selon différentes variantes. Nous avons mesuré le bruit fréquentiel de nos détecteurs puis leur sensibilité à un flux infrarouge. Les meilleurs dispositifs montrent une limite de sensibilité de 30 pW/√Hz. Une résolution sur la scène (NETD) de 2 K est obtenu pour un temps d’intégration adapté au temps image. Ces performances sont inégalées pour un résonateur non refroidi à ces dimensions. Nous montrons qu’un NETD de 20 mK est atteignable au pas de 12 µm (pour un temps de réponse de 10 ms) en se focalisant sur 3 axes de recherche : une cointégration des résonateurs avec leur électronique de lecture, une acquisition plus précise du signal par un temps d’intégration adapté au temps image et l’amélioration de la sensibilité thermique (TCF) du résonateur d’un facteur 10. Pour ce dernier point, nous présentons des méthodes afin d’améliorer le TCF. Finalement, nous étudions des architectures de pixels au pas de 5 µm présentant des performances théoriques proches de celles requises par l’imagerie infrarouge (NETD=70 mK et τth=8 ms). Des perspectives de transductions tout optiques sont finalement évoquéesProgress in microelectronics has been mainly driven by informatics needs for addressing both increased performances and lower costs for processors and memories, according to the well-known Moore’s Law. For many years, these tremendous progresses in silicon fabrication and integration have also contributed to the emergence of new type of devices, such as sensors, actuators, filters, clocks or imagers, forming a new class of devices called More than Moore. Uncooled infrared imaging, which uses thermal sensors belongs to this new class of devices. Today thermal sensors principally use a thin resistive layer (mainly vanadium dioxide or amorphous silicon) on a suspended membrane as a thermometer and are called microbolometers. The fabrication cost of thermal cameras has dramatically dropped over the last 20 years, while attaining performances close to the expensive cooled cameras. Nevertheless, the cost of these imagers still remains too high for consumer market (night driving, smartphones, home automation) whereas military applications (surveillance, personal googles) need improved resolutions – in an affordable camera. Therefore, one objective of the microbolometers industry roadmap is to scale down the sensor surface – the pixel pitch – in order to increase the number of imagers fabricated on a silicon wafer. Yet, the pixel pitch reduction goes necessarily with a reduction of the captured infrared power leading to a reduction of the sensor signal. As a consequence, the sensor sensitivity needs to be improved as the pixel pitch scales down. The resistive technology has managed this scaling so far, down to 17µm pixel pitch, allowing a densification of the sensors by a factor 4 every 5 years. Despite this success, the scaling has been recently slowed down, mostly because of microbolometers self-heating issue and 1/f noise which are inherent to the resistive transduction. Our work has focused on a new type of sensor at 12µm pixel pitch, which theoretically gets rid of self-heating and 1/f noise. In our approach, an absorbing plate is excited at its mechanical resonance through two tiny torsion arms using an actuation electrode placed 2µm underneath. Pixel motion is also transduced electrostatically. Since micromechanical resonators feature very low frequency noise, we believe that an uncooled infrared sensor based on the monitoring of its resonance frequency (which changes with temperature through the TCF) should be extremely sensitive. In our work, we present different models (linear and nonlinear) for the pixel mechanical behavior and compare them to experimental characterization of resonators which were fabricated in dense arrays, according to several designs. We measure the frequency stability of our sensors along with their sensitivity to infrared flux. The best devices show a resolution of 30pW/sqrt(Hz), with a response time lower than one millisecond. The scene resolution (NETD) is 2K for an integration time compatible with imaging frame rate. These performances overtake results previously published on this topic with such reduced pixel pitch. We show that a NETD of 20mK (with a response time of 10ms) is reachable at 12µm pixel pitch if we can address the following 3 challenges: a cointegration of the resonators with their electronics, a shared readout of several pixels in the imaging frame rate and an improved TCF by a factor 10. Therefore, we provide different methods in order to improve the TCF. Finally, we present different pixel designs at 5µm pixel pitch which show theoretical performances close to uncooled infrared imaging requirements (NETD=70mK and tau_th=8ms). An optical transduction may also be a new route toward even better signal to noise ratio at low pitch
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Balakireva, Irina. "Nonlinear dynamics of Kerr optical frequency combs." Thesis, Besançon, 2015. http://www.theses.fr/2015BESA2043.
Full textAbstract:
La présente thèse est consacrée à l’étude des peignes optiques de Kerr dans les résonateurs àmodes de galerie, au sein desquels la lumière peut être excitée par pompage externe. L’effet Kerrexistant dans ces résonateurs engendre des modes latéraux équidistants (dans le domaine spectral)de part et d’autre du mode excité, c’est à dire un peigne de fréquence. Cette thèse est diviséeen trois chapitres. Le premier est dédié à l’introduction de la génération de ces peignes et leurapplications. Le deuxième chapitre présente l’analyse de l’équation de Lugiato-Lefever, décrivantde manière analytique le système, et conduit à la construction de deux diagrammes de bifurcationpour les dispersions normale et anomale. Ils sont tracés en fonction des deux seuls paramètresexpérimentalement contrôlables une fois le résonateur fabriqué : la puissance du laser et sondécalage de fréquence. Ces diagrammes indiquent les plages de paramètres pour lesquels une,deux, ou trois solutions existent ainsi que leur stabilité. Les simulations numériques renseignentle type exact de solution associée à chaque aire (notamment les solitons brillants et sombres, lesbreathers, les peignes optiques de Kerr de premier et deuxième ordre, et un régime chaotique) ; cesdiagrammes indiquent donc les paramètres du laser à choisir afin de générer la solution souhaitée.Le troisième chapitre est dédié aux peignes de Kerr optique secondaires, lignes additionnelles dansle domaine spectral générées entre les lignes du peigne principal. Ils apparaissent en dispersionanormale, lorsque la quantité de photon pompe excède un seuil dit de second ordre, qui a étédéterminé numériquementThis thesis is dedicated to the study of the Kerr optical frequency combs in whispering gallery moderesonators, where the light can be excited by the extern pump. Due to the Kerr effect existing in theseresonators, the quasi-equidistant lines in the spectral domain are generated around the excited mode,that is the frequency comb. This thesis is devided in three chapters. The first one is dedicated to theintroduction of the Kerr comb generation and their applications.The second one presents the analysisof the Lugiato-Lefever equation used for the analytical study of the system, leading to the constructionof two bifurcation diagrams for the normal and anomalous dispersions. They are plotted for twoparameters, which can be controlled during experiments once the resonator has been fabricated,which are the pump power of the laser and its frequency detuning. These diagrams show the areas ofthe parameters for which one, two, or three solutions exist and their stability. The additional numericalsimulations show the exact type of the solution in each area (such as the bright and dark solitons,the breathers, the primary and secondary Kerr combs and chaotical regimes), finally these diagramsshow the parameters of the laser needed to be choosen for the generation of the desired solution.The third chapter is dedicated to the secondary Kerr combs, which are the additional lines generatedbetween the lines of the primary comb. They appear in the anomalous dispersion regime, when thequantity of the pump photons crosses the second-order threshold, which has been found numerically
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Sundaresan, Krishnakumar. "Temperature Compensated CMOS and MEMS-CMOS Oscillators for Clock Generators and Frequency References." Diss., Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/13977.
Full textAbstract:
Silicon alternatives to quartz crystal based oscillators to electronic system clocking are explored. A study of clocking requirements reveals widely different specifications for different applications. Traditional CMOS oscillator-based solutions are optimized for low-cost fully integrated micro-controller clock applications. The frequency variability of these clock generators is studied and techniques to compensate for this variability are proposed. The efficacy of these techniques in reducing variability is proven theoretically and experimentally. MEMS-resonator based oscillators, due to their exceptional quality factors, are identified as suitable integrated replacements to quartz based oscillators for higher accuracy applications such as data converter clocks. The frequency variation in these oscillators is identified and techniques to minimize the same are proposed and demonstrated. The sources of short-term variation (phase noise) in these oscillators are discussed and an inclusive theory of phase noise is developed. Techniques to improve phase noise are proposed. Findings from this research indicate that MEMS resonator based oscillators, may in future, outperform quartz based solutions in certain applications such as voltage controlled oscillators. The implications of these findings and potential directions for future research are identified.
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Gutierrez, Napoléon. "Peignes de fréquences optiques par effet Kerr dans les micro et mini résonateurs optiques." Thesis, Toulouse 3, 2019. http://www.theses.fr/2019TOU30273.
Full textAbstract:
Les peignes de fréquences optiques trouvent de nombreuses applications dans les domaines de l'optique, la physique, la spectroscopie et l'optoélectronique entre autres. Le laser à verrouillage de modes est, historiquement, le système à l'origine de ces peignes de fréquences. Plus récemment, dans la quête pour la miniaturisation des générateurs de peignes de fréquences optiques, les micro-résonateurs et mini-résonateurs ont émergé comme des alternatives attirantes grâce à leur compacité et aux propriétés d'accumulation de puissance, de sélectivité modale et de stabilité mécanique. Les travaux de thèse présentés ici portent sur l'étude et la modélisation des peignes Kerr à base de résonateurs passifs. Le premier chapitre fait un état de l'art des micro et mini peignes Kerr et met en avant les avantages de ces plateformes pour la génération de peignes de fréquences optiques. Le deuxième chapitre présente le formalisme utilisé pour l'étude des résonateurs passifs en régime linéaire et non-linéaire. L'approche non-linéaire est basée sur un modèle itératif issu des travaux d'Ikeda, permettant d'étudier la formation de peignes Kerr dans les résonateurs passifs. Dans le troisième chapitre, des résultats de génération de peignes Kerr dans un résonateurs intégré sont présentés et confrontés à des résultats de simulations basés sur le modèle introduit dans le chapitre qui précède. Le dernier chapitre vise à étudier l'impact d'un couplage d'accès non idéal sur la génération de peignes Kerr dans les résonateurs passifs. Des simulations sont présentées, mettant en lumière l'influence importante du choix du coupleur sur le type de peigne généré par l'ensemble résonateur-coupleurOptical frequency combs find applications in optics, physics, precision spectroscopy and opto-electronics among others. The mode-locked laser is historically the system at the origin of these combs. More recently, in the quest for the miniaturization of optical frequency comb generators, micro-resonators and mini-resonators have emerged as attractive alternatives due to their compact nature as well as their mode selectivity and power enhancement properties. The work presented in this thesis is centered on the modeling of passive resonator based Kerr frequency combs. The first chapter of this thesis presents a state of the art of micro and mini Kerr frequency combs and puts forth the advantages of resonator-based platforms for the generation of optical frequency combs. The second chapter presents the model used to study passive optical resonators in the linear and non-linear regimes. The non-linear approach is based on an Ikeda map, allowing the study of Kerr comb formation in passive resonators. In the third chapter, Kerr frequency combs generated in an integrated resonator are presented. These results are compared to simulation results based on the model presented in the preceding chapter. The last chapter studies the impact of frequency-dependent access coupling parameters on the generation of Kerr frequency combs. Simulation results are presented, bringing to light the importance of the influence that these coupling parameters have on the combs generated in the resonator
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Laquerbe, Vincent. "Étude théorique et expérimentale d’un nouveau concept d’antenne VHF miniature et accordable par décharge plasma." Thesis, Toulouse, ISAE, 2017. http://www.theses.fr/2017ESAE0039/document.
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La miniaturisation d’antenne est un défi important, en particulier en bande VHF où les longueurs d’onde sont grandes. Parmi les différentes techniques rencontrées dans la littérature, une approche théorique originale repose sur l’utilisation de la résonance électrostatique de sphères sub-longueur d’onde de permittivité négative (ENG pour Epsilon NeGative). L’implémentation pratique de cette solution en considérant une décharge plasma comme milieu ENG est étudiée dans ces travaux de thèse. Le plasma laisse entrevoir des potentialités intéressantes pour ce type d’antennes miniatures comme la furtivité et la reconfigurabilité en fréquence. Dans un premier temps, différents modèles analytiques sont développés afin étudier le comportement électromagnétique de petites sphères réalistes de plasma. Ces modèles permettent par ailleurs la construction de schémas numériques précis et adaptés aux simulateurs électromagnétiques commerciaux. Dans un second temps, un prototype fonctionnel est méthodiquement conçu. La solution proposée permet l’intégration du système d’excitation de la décharge plasma au sein de l’antenne sans en perturber son fonctionnement nominal. Ce prototype permet la caractérisation des paramètres plasma de la décharge et du comportement électromagnétique du résonateur sphérique à plasma. Enfin, un travail annexe d’intégration de décharges plasma dans des circuits planaires en technologie micro-ruban est présenté. Les conceptions, modélisations et caractérisations expérimentales de ces résonateurs planaires permettent de mettre en évidence les capacités du plasma pour leur accordabilité en fréquenceAntenna miniaturisation is a major issue, especially in the VHF band whose wavelengths are significant. Amongst the solution in the litterature, a recent theoretical technique relies upon the electrostatic resonance of negative permittivity (ENG) subwavelength spheres. In this work, the use of a plasma discharge as ENG medium is under consideration. Plasma indeed suggests new potentialities for this kind of small antennas, such as stealth and frequency agility. Firstly, several analytical models are developed to study the electromagnetic response of subwavelength realistic plasma spheres. These models further allow to derive accurate numerical representations that fit commercial electromagnetic solvers. A working prototype that comprises a plasma ignition system within the antenna structure without altering its operation is then designed. It is used to both characterize the plasma discharge and the electromagnetic behavior of the plasma spherical resonator. Finally, this work is extended to the case of planar circuits by integrating a plasma discharge inside microstrip resonators. The design, the modeling and the experimental studies of these resonators highlight the ability of the plasma to tune the resonant frequency
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Weed, Matthew. "Wavelength scale resonant structures for integrated photonic applications." Doctoral diss., University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5888.
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An approach to integrated frequency-comb filtering is presented, building from a background in photonic crystal cavity design and fabrication. Previous work in the development of quantum information processing devices through integrated photonic crystals consists of photonic band gap engineering and methods of on-chip photon transfer. This work leads directly to research into coupled-resonator optical waveguides which stands as a basis for the primary line of investigation. These coupled cavity systems offer the designer slow light propagation which increases photon lifetime, reduces size limitations toward on-chip integration, and offers enhanced light-matter interaction. A unique resonant structure explained by various numerical models enables comb-like resonant clusters in systems that otherwise have no such regular resonant landscape (e.g. photonic crystal cavities). Through design, simulation, fabrication and test, the work presented here is a thorough validation for the future potential of coupled-resonator filters in frequency comb laser sources.Ph.D.
Doctorate
Optics and Photonics
Optics and Photonics
Optics
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Shao, Botao. "Fully Printed Chipless RFID Tags towards Item-Level Tracking Applications." Doctoral thesis, KTH, Elektroniksystem, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-142409.
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An ID generating circuit is unquestionably the core of a chipless RFID tag. For convenience of printing process and cost consideration, the circuit should be kept as simple as possible. Based on the cognition, an 8-bit time-domain based ID generating circuit that merely consists of a ML and eight capacitors was offered, and implemented on photo-paper substrates via inkjet printing process. In addition to the experimental measurements, the circuit was also input into circuit simulators for cross-validation. The good agreement between simulations and measurements is observed, exhibiting the tag technical feasibility. Besides of low cost, the tag has wide compatibility with current licensed RFID spectrum, which will facilitate the future deployment in real applications. Compared to time-domain based chipless tags, frequency signatures based chipless RFID tags are expected to offer a larger coding capacity. As a response, we presented a 10-bit frequency-domain based chipless RFID tag. The tag composed of ten configurable LC resonators was implemented on flexible polyimide substrate by using fast toner-transferring process. Field measurements revealed not only the practicability of the tag, but also the high signal to noise ratio (SNR). Another frequency domain tag consists of a configurable coplanar LC resonator. With the use of all printing process, the tag was for the first time realized on common packaging papers. The tag feasibility was confirmed by subsequent measurements. Owing to the ultra-low cost potential and large SNR, The tag may find wide applications in typical RFID solutions such as management of paper tickets for social events and governing of smart documents. Ultra wide band (UWB) technology possesses a number of inherent merits such as high speed communication and large capacity, multi-path immunity, accurate ranging and positioning, penetration through obstacles, as well as extremely low-cost and low- power transmitters. Thus, passive UWB RFIDs are expected to play an important pole in the future identification applications for IoT. We explained the feature difference between UWB chipless tags and chip based tags, and forecasted the applications respectively based on the comparison between the two technologies. It is expected that the two technologies will coexist and compensate each other in the applications of IoT. Lastly, the thesis ends up with brief summary of the author’s contributions, and technical prospect for the future development of printable chipless RFID tags.QC 20140304
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Ekmekci, Evren. "Design, Fabrication And Characterization Of Novel Metamaterials In Microwave And Terahertz Regions: Multi-band, Frequency-tunable And Miniaturized Structures." Phd thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612730/index.pdf.
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This dissertation is focused on the design, fabrication, and characterization of novel metamaterials in microwave and terahertz regions with the following outcomes:
A planar µ-negative metamaterial structure, called double-sided SRR (DSRR), is proposed in the first part of this study. DSRR combines the features of a conventional split ring resonator (SRR) and a broadside-coupled SRR (BC-SRR) to obtain much better miniaturization at microwave frequencies for a given physical cell size. In addition to DSRR, double-sided multiple SRR (DMSRR), double-sided spiral resonator (DSR), and double-sided U-spiral resonator (DUSR) have been shown to provide smaller electrical sizes than their single-sided versions under magnetic excitation. In the second part of this dissertation, a novel multi-band tunable metamaterial topology, called micro-split SRR (MSSRR), is proposed. In addition to that, a novel magnetic resonator structure named single loop resonator (SLR) is suggested to provide two separate magnetic resonance frequencies in addition to an electric resonance in microwave region. In the third part, two different frequency tunable metamaterial topologies called BC-SRR and gap-to-gap SRR are designed, fabricated and characterized at terahertz frequencies with electrical excitation for the first time. In those designs, frequency tuning based on variations in near field coupling is obtained by in-plane horizontal or vertical displacements of the two SRR layers. The values of frequency shifts obtained for these tunable metamaterial structures are reported to be the highest values obtained in literature so far. Finally, in the last part of this dissertation, novel double-sided metamaterial based sensor topologies are suggested and their feasibility studies are presented.
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Волошин, Антон Олександрович. "Мікромеханічно перелаштовувані антенні елементи НВЧ." Doctoral thesis, Київ, 2020. https://ela.kpi.ua/handle/123456789/36406.
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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.
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Terblanche, Phillip. "Electronically adjustable bandpass filter." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/17966.
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Thesis (MScEng)--Stellenbosch University, 2011.ENGLISH ABSTRACT: This thesis presents the study, analysis and design of electronically tunable filters, that can be tuned over a wide frequency range (20-500MHz), for use in a direct sampling receiver. The final design does not have to be a single filter, but may be comprised of a filter bank which enables switching between the filters. The band of interest is too low to use normal transmission lines and lumped elements have to be used. Different topologies that can implement Coupled Resonator filters with lumped elements are investigated. Devices that can be used for tuning are also investigated and varactor diodes are found to be the most suitable tuning devices currently available. Two filters, one at the high-end and one at the low-end of the band, were designed and built, both using varactor diodes. These filters perform well in terms of tuning range, but achieving low losses with current technologies in this band remains difficult.
AFRIKAANSE OPSOMMING: Hierdie tesis meld die studie, analise en ontwerp van elektronies verstelbare filters, wat verstelbaar is oor ’n wye band (20-500MHz), vir gebruik in ’n direk-monster-ontvanger. Die finale ontwerp hoef nie ’n enkele filter te wees nie, maar kan bestaan uit ’n filterbank wat skakeling tussen die filters toelaat. Die betrokke band is te laag vir die gebruik van normale transmissielyne en diskrete komponente moet gebruik word. Verskillende topologieë wat gekoppelde resoneerder filters implementeer met diskrete komponente is ondersoek. Verstelbare komponente word ook ondersoek en varaktor diodes blyk die mees geskikte verstelbare komponent wat huidig beskikbaar is in hierdie band. Twee filters, een aan die hoë kant en een aan die lae kant van die band, is ontwerp en gebou, beide met varaktor diodes. Hierdie filters het wye verstelbare bereik, maar dit is steeds moeilik om verliese te beperk met die huidige tegnologie.
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Олійник, Ольга Юріївна. "Науково-методологічні засади віброчастотного контролю технологічних параметрів в умовах вібрації." Thesis, Національний технічний університет "Харківський політехнічний інститут", 2019. http://repository.kpi.kharkov.ua/handle/KhPI-Press/42234.
Full textAbstract:
Дисертація на здобуття наукового ступеня доктора технічних наук за спеціальністю 05.11.13 – прилади і методи контролю та визначення складу речовин» ‒ Державний вищий навчальний заклад «Український державний хіміко-технологічний університет», МОН України, Дніпро, 2019. Дисертація присвячена вирішенню науково-прикладної проблеми підвищення достовірності контролю технологічних параметрів (густини, в’язкості, зусилля (тиску)) в умовах вібрації за рахунок розроблення нових математичних моделей та методів визначення технологічних параметрів, застосування нових багатопараметричних віброчастотних перетворювачів з універсальною характеристикою та змінним співвідношенням сигнал-шум, розробки програмних засобів фільтрації зашумленої вимірювальної інформації з невідомими законами розподілу. Розроблено віброчастотний метод контролю та вимірювання густини, в’язкості, зусилля (тиску) газорідинних середовищ у виробничих умовах, який реалізується за допомогою віброчастотного вимірювального перетворювача з трубчатим, циліндричним резонатором у якості якого може використовуватись частина технологічного апарату, отримано математичні моделі амплітудно- частотних характеристик технологічних параметрів в апаратах різного типа конструкції. Розроблено теоретичні основи проектування неметалевих трубчатих проточних резонаторів з широкою сферою застосування. Розроблено багатофункціональний віброчастотний перетворювач для вимірювання густини, в’язкості, зусилля (тиску) з циліндричним резонатором, який має універсальну характеристику. Виконані дослідницькі роботи щодо попередньої ідентифікації законів розподілу, розроблено алгоритм фільтрації Калмана вимірювальної інформації з підвищеними завадами та структура багатопараметричної системи контролю технологічних параметрів з системою діагностики форми коливань резонатора; вдосконалено пристрій для ідентифікації активного стану оператора. Здійснені впровадження інженерних розробок дисертаційної роботи на провідних підприємствах Дніпра та за кордоном.Thesis for a degree of Doctor of Science (Technology), Specialty 05.11.13 – Instruments and Methods of Control and compounds` composition determination. – State Higher Educational Institution «Ukrainian State Chemical-Technological University», Ministry of Education and Science of Ukraine, Dnipro, 2019. The dissertation is devoted to solving the scientific and applied problem of increasing the reliability of the control of technological parameters (density, viscosity, force (pressure)) in a production environment through the development of new mathematical models and methods for determining technological parameters from the amplitude-frequency characteristics of the oscillatory environment of apparatuses, the use of new multiparameter vibration frequency converters with a universal characteristic and variable signal-to-noise ratio, as well as software development STV filtering noisy measurement information with unknown distribution laws. A vibration frequency method has been developed for monitoring and measuring the density, viscosity, force (pressure) of gas-liquid media under industrial conditions using a measuring transducer with a tubular, cylindrical resonator, mathematical models of the amplitude-frequency characteristics of technological parameters in devices of various designs are obtained. Theoretical foundations have been developed for the design of non-metallic tubular flow resonators with a wide scope. A multifunctional vibration frequency converter has been developed for measuring density, viscosity, force (pressure) with a cylindrical resonator, which has a universal characteristic. Research work on the identification of distribution laws has been completed, an Kalman filtering algorithm has been developed for measuring information with increased noise, and the structure of a multidimensional control system for technological parameters with a system for diagnosing the shape of resonator vibrations; improved device for identifying the active state of the operator. Implementation of engineering developments of the thesis was carried out at the leading enterprises of the Dnieper and abroad.
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Somer, Jakub. "Využití tlustých vrstev v moderní elektronice." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220230.
Full textAbstract:
Tato diplomová práce se zabývá technologií tlustých vrstev a jejím možným použitím pro nekonvenční aplikace. První část práce je rešeršní a zaměřuje se především na aplikace tlustovrstvé technologie v různých oblastech použití. V teoretické části práce je dále popsána technologie LTCC, včetně technologických postupů výroby. V praktické části jsou řešeny dvě aplikace v tlustovrstvé technologii. Jedná se návrh a výrobu vysokofrekvenčního filtru a optického senzoru tlaku technologií LTCC. V závěru práce jsou provedena měření a jsou zhodnoceny dosažené výsledky.
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Florián, Antonín. "Synchronizované zdroje časových signálů." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-220289.
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This thesis deals with design of synchronized sources of time signal. The first part of the thesis deals with the theory the crystal resonators, crystal oscillators and PLL. The second part of the thesis deals with the crystal oscillator with 10MHz frequency. In the oscillator is use of SC cut crystal. The third part of the work deals with method of synchronization. To synchronization is use of PLL.
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Haller, Kristian. "Nonlinear Acoustics Applied to NonDestructive Testing." Licentiate thesis, Karlskrona : Blekinge Institute of Technology, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-00374.
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Sensitive nonlinear acoustic methods are suitable for material characterization. This thesis describes three nonlinear acoustic methods that are proven useful for detection of defects like cracks and delaminations in solids. They offer the possibility to use relatively low frequencies which is advantageous because attenuation and diffraction effects are smaller for low frequencies. Therefore large and multi-layered complete objects can be investigated in about one second. Sometimes the position of the damage is required. But it is in general difficult to limit the geometrical extent of low-frequency acoustic waves. A technique is presented that constrains the wave field to a localized trapped mode so that damage can be located.
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Черченко, Максим Олександрович. "Пристрої НВЧ на основі тонких діелектричних резонаторів." Master's thesis, Киів, 2018. https://ela.kpi.ua/handle/123456789/25868.
Full textAbstract:
Актуальність теми
Застосування діелектричних резонаторів в електроніці НВЧ сприяє створенню високоефективних резонансних пристроїв. Вдосконалення характеристик цих систем є актуальною задачею.
Зв'язок роботи з науковими програмами, планами, темами.
Робота пов’язана з науковими програмами, планами та темами що розроблюються на кафедрі.
Мета і задачі дослідження.
Метою даної робити є вдосконалення пристроїв НВЧ на основі тонких діелектричних резонаторів.
Для досягнення мети, необхідно виконати наступні задачі:
1. Проаналізувати існуючі структури НВЧ.
2. Дослідити структури НВЧ на основі тонких діелектричних резонаторів.
3. Показати перспективність конструювання пристроїхв НВЧ на основі тонких діелектричних резонаторів.
Об’єктом дослідження є структури НВЧ на основі тонких діелектричних резонаторів.
Предметом дослідження є електродинамічні властивості і характеристики тонких діелектричних резонаторів.
Методика наукового дослідження включає: методи аналізу НВЧ-пристроїв, аналітичне моделювання.
Практичне значення одержаних результатів.
Запропоновано конструкції керованого фазообертача на основі тонких діелектричних резонаторів, що дозволило знизити керуючу напругу.
Особистий внесок здобувача:
• Експериментально досліджено електродинамічні характеристики фазообертачів на основі тонких діелектричних резонаторів.
• Запропоновано конструкції фазообертачів із зниженою керуючою напругою.
Структура і об'єм роботи.
Робота складається зі вступу, шістьох розділів, висновків та списку використаних джерел. Загальний обсяг дисертації становить 76 сторінки. Робота включає 16 рисунків, 29 таблиць, список використаних джерел з 26 найменувань.Actuality of theme The use of dielectric resonators in microwave electronics helps to create highly effective resonance devices. Improving the characteristics of these systems is an urgent task. Relationship of work with scientific programs, plans, themes. The work is connected with the scientific programs, plans and themes that are being developed at the department. The purpose and tasks of the study. The purpose of this work is to improve the microwave devices based on thin dielectric resonators. To achieve the goal, you need to accomplish the following tasks: 1. Analyze existing microwave structures. 2. To study the microwave structure on the basis of thin dielectric resonators. 3. Show the prospect of designing devices on microwave based on thin dielectric resonators. The object of the study is the structure of microwave based on thin dielectric resonators. The subject of the study is electrodynamic properties and characteristics of thin dielectric resonators. The method of scientific research includes: methods of analysis of microwave devices, analytical modeling. The practical value of the results. The designs of a controlled phase rotator on the basis of thin dielectric resonators were proposed, which allowed to reduce the control voltage. The applicant's personal contribution: • Electrodynamic characteristics of phase rotators on the basis of thin dielectric resonators have been experimentally investigated. • The designs of phase rotators with reduced control voltage are proposed. Structure and volume of work. The work consists of an introduction, six sections, conclusions and a list of sources used. The total volume of the dissertation is 76 pages. The work includes 16 drawings, 29 tables, list of used sources from 26 titles.
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Ліщиновська, Наталія Олександрівна, Наталия Александровна Лищиновская, and Nataliya Oleksandrivna Lishchinovska. "Метод синтезу розподілених високодобротних резонаторів з розрідженим діапазоном частот для радіотехнічніх пристроїв та засобів телекомунікацій." Thesis, Національний авіаційний університет, 2021. https://er.nau.edu.ua/handle/NAU/47244.
Full textAbstract:
В роботі сформульовано та вирішено актуальне наукове завдання щодо
розробки науково-методичного апарату синтезу високодобротних резонаторів з
розрідженим спектром для фільтруючих систем засобів телекомунікацій.
Вирішення поставленого наукового завдання забезпечує розрахунок і
можливість побудови фільтруючої системи зі зниженим затуханням в смузі
пропускання і розширеною областю затримання, що дозволяє підвищити
ефективність роботи телекомунікаційних пристроїв.
На основі спектрального підходу розроблено метод синтезу резонаторів на
нерегулярних лініях передачі. На відміну від відомих способів побудови
резонаторів запропонований метод дозволяє одночасно синтезувати розподілені 8
коливальні системи за заданим розподілом резонансних частот в заданій
частотній області і величиною добротності основного типу коливань. Показано,
що спектральний метод найбільш ефективний при синтезі неоднорідних
резонаторів з врахуванням втрат. Розроблено топології полоскових і
коаксіальних резонаторів, що мають максимальну добротність.В результате проведенного анализа методов построения резонаторов установлено, что наиболее перспективными на данном этапе развития распределённых устройств средств телекоммуникаций и промышленного производства радиотехнических материалов, являются устройства селекции на отрезках неоднородных полосковых и коаксиальных линий передачи, обеспечивающих заданную разрядку спектра резонансных частот и имеющих максимально высокую добротность. Однако при реализации таких устройств разработчики сталкиваются с серьёзными трудностями, обусловленными отсутствием аналитических выражений для расчёта добротности резонансных систем, отсутствием методов синтеза высокодобротных резонаторов, а также с отсутствием алгоритмов расчёта их конструктивных параметров. Кроме того, для большинства разработанных устройств не обоснован выбор допусков при изготовлении, что вызывает необходимость регулировок и ведёт к большему проценту брака и повышению себестоимости при производстве. Разработан метод синтеза высокодобротных резонансных систем с позиций спектральной теории неоднородных линий в сочетании с методами численного синтеза. Идея предложенного метода синтеза резонаторов состоит в следующем. Из теории длинных линий известно, что входное сопротивление линии однозначно определяет закон изменения волнового сопротивления. Следовательно, для построения резонатора, обладающего требуемыми электрическими характеристиками надо сформировать его входное сопротивление, в котором были бы заложены все необходимые свойства резонансной системы. В работе в качестве системы универсальных параметров предложено использовать резонансные частоты (спектр линии) и вычеты сопротивления резонатора на резонансных частотах. Тогда, изменяя положение резонансных частот в рабочей области можно добиться заданного положения основной (рабочей) резонансной частоты и требуемого распределения нерабочих (паразитных) резонансов, которые обуславливают паразитные полосы пропускания частотных фильтров. Что касается выбора вычетов на резонансных частотах, то их можно выбрать исходя из дополнительных условий. В качестве данного условия в работе предложено использовать добротность резонатора на основной частоте. Таким образом, изменением спектра в нерабочей области и вычетов на всех частотах спектра можно получить заданное значение добротности основного резонанса. В работе рассмотрены неоднородные линии с потерями В отличие от существующих методов построения резонаторов, ориентированных в основном на однородные линии, получены уточняющие аналитические выражения, позволяющие определять добротность при произвольных зависимостях волнового сопротивления и распределённых потерь от координаты. Разработана математическая модель резонатора, отличительной особенностью которой является минимальное число варьируемых параметров при использовании численных методов оптимизации. На основе этой модели осуществлён синтез резонаторов по полюсам и вычетам входного сопротивления и построена его целевая функция. С использованием численных методов оптимизации (метод скользящего допуска, метод деформированного многогранника) найдены оптимальные значения полюсов и вычетов входного сопротивления резонатора, которые однозначно определяют волновое сопротивление резонатора, обладающего максимальной добротностью при заданном распределении резонансных частот. Разработаны алгоритмы синтеза нерегулярных высокодобротных резонаторов, которые ориентированы на типы неоднородных линий, наиболее часто используемых на практике (коаксиальная, микрополосковая, симметричная полосковая). Предложенные алгоритмы отличаются от известных использованием минимального количества варьируемых параметров и позволяют определить волновое сопротивление резонатора с максимально возможной добротностью. Осуществлена оценка допусков по контролю в процессе производства наиболее важных параметров конструкции и диэлектрических материалов, используемых при изготовлении резонаторов. Разработаны топологии полосковых и коаксиальных резонаторов, имеющих максимальную добротность.
In the robot, the scientific development of the development of a scientificmethodical apparatus for the synthesis of high-quality resonators with a developed spectrum for filter systems for telecommunication systems has been formulated. The renewal of the supplied science department will ensure the development of the system and the ability to induce the filtering system to reduce the attenuation in smoothies and the broadened area of operation, as well as allowing the development of telecommuting efficiency. On the basis of the spectral approach, the method for the synthesis of resonators on irregular transmission lines has been broken up. On the basis of different ways of stimulating the resonators in the proponation, the method allows one hour to synthesize the generation of colival systems for a given rise of resonance frequencies in a given frequency region and the value of the quality factor of the main type of colivan. It is shown that the spectral method is the most effective in the synthesis of non-uniform resonators with interruptions. The topology of strip and coaxial resonators has been broken down to provide the maximum quality factor.
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Calhoun, Paul Jacob 1979. "Frequency synthesis using MEMS piezoelectric resonators." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/28897.
Full textAbstract:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2004.Includes bibliographical references (p. 79).
(cont.) Ultimately, this thesis presents two approaches to frequency synthesizer design. The first uses frequency windows of approximately 200 MHz. The 800 MHz to 1 GHz matching network is presented in detail along with predicted performance capabilities across this frequency range. The second design implements matching networks with variable capacitors and a variable load impedance. CAD performance simulations validate the broadband switched array design concept, and represent a first step towards realizing a new, commercially viable RF MEMS oscillator and switched array frequency synthesizer. The views expressed in this article are those of the author and do not reflect the official policy or position of the United States Air Force, Department of Defense, or the U.S. Government.
This thesis explores the foundational issues in oscillator and frequency synthesizer design using an integrated MEMS piezoelectric resonator. It presents an original low phase-noise oscillator design and two frequency synthesizer designs using the emerging technology of Draper Laboratory's MEMS GHz-range resonator. The designs leverage the extremely small size and high Q of this MEMS resonator to develop integrable, energy efficient, low phase noise oscillators and frequency synthesizers. The circuits presented offer significant size and flexibility advantages over present designs, while promising exceptional performance. First, a 1 GHz frequency oscillator design is described incorporating the longitudinal mode bar (L-Bar) resonator with a SiGe bipolar junction transistor (BJT) in a one-port reflection topology. This design choice was made to minimize circuit complexity when later employed in a frequency synthesizer with a broadband array of switched resonators. Harmonic frequency matching is considered in a trade study between phase noise, efficiency, and circuit complexity. Performance was further enhanced using a novel approach for selecting the target static negative impedance looking into the transistor. This method modifies the transistor base current and matching networks in a manner that allows simultaneous optimization of phase noise and efficiency. The resulting oscillator has size and predicted performance characteristics that are unachievable using present technology. Second, the matching networks from the 1 GHz oscillator are altered to allow for oscillation over a frequency range selected by an array of switched resonators. The resulting frequency synthesizer is designed to operate in the range of 200 MHz to 1 GHz.
by Paul Jacob Calhoun.
S.M.
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Hopcroft, Matthew A. "Temperature-stabilized silicon resonators for frequency references /." May be available electronically:, 2007. http://proquest.umi.com/login?COPT=REJTPTU1MTUmSU5UPTAmVkVSPTI=&clientId=12498.
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Олійник, Ольга Юріївна. "Науково-методологічні засади віброчастотного контролю технологічних параметрів в умовах вібрації." Thesis, Національний технічний університет "Харківський політехнічний інститут", 2019. http://repository.kpi.kharkov.ua/handle/KhPI-Press/42235.
Full textAbstract:
Дисертація на здобуття наукового ступеня доктора технічних наук за спеціальністю 05.11.13 – «прилади і методи контролю та визначення складу речовин». ‒ Державний вищий навчальний заклад «Український державний хіміко-технологічний університет» Міністерства освіти і науки України, Дніпро, 2019. ‒ Національний технічний університет «Харківський політехнічний інститут» Міністерства освіти і науки України. Дисертація присвячена вирішенню науково-прикладної проблеми впідвищення достовірності контролю технологічних параметрів (густини, в’язкості, зусилля (тиску)) в умовах выбрації (технологічних апратах та обладнанні) за рахунок розроблення нових математичних моделей та методів визначення технологічних параметрів за амплітудно-частотними характеристиками коливального середовища апаратів, застосування нових багатопараметричних віброчастотних перетворювачів з універсальною характеристикою та змінним співвідношенням сигнал-шум, отриманих завдяки використанню автоколивальної системи зі стабільними характеристиками на першій гармоніці без застосування додаткових частотних фільтрів, розробки програмних засобів фільтрації зашумленої вимірювальної інформації з невідомими законами розподілу Проведено аналіз сучасних підходів до вимірювання технологічних параметрів (густини, в’язкості, зусилля (тиску) у виробничих умовах, що характеризуються підвищеною вібрацією, встановлені фактори, що вносять найсуттєвіший вплив на викривлення результатів вимірювання і створюють додаткові похибки, запропоновані методи компенсації впливу зазначених факторів. Існуючі методи неруйнівного контролю не задовольняють поставленим завданням, оскільки не дають можливості контролювати швидкоплинні технологічні процеси, а створення штучної коливальної системи не дає змогу контролювати амплітудно-частотні характеристики природної коливальної системи, що виникає в апараті. Вперше отримано математичні моделі статичних характеристик перетворення для розробленого віброчастотного методу вимірювання технологічних параметрів (густини, в’язкості, зусилля (тиску) в апаратах з природними коливальними системам для типу конструкції апаратів «труба», «циліндр» та для апаратів з барботажем та пульсацією середовища на основі гіпотез Сорокіна та Кірхгофа-Лява у виробничих умовах, що дозволяють визначати вказані параметри за амплітудно-частотними характеристиками природних коливальних систем у апаратах та зменшити динамічну похибку каналу вимірювання параметру більш ніж у 10 разів (0,012 %). Запропановано теоретичні основи проектування неметалевих трубчатих проточних резонаторів з широкою сферою застосування (вимірювання густини рідких і газоподібних середовищ, концентрації розчинів, температурного коефіцієнта, модуля пружності матеріалу) конструкція яких дозволяє підвищити точність вимірювання за рахунок регулювання активної частини резонатора з урахуванням жорсткості (піддатливості) типу кріплення і його розташування. Метод визначення частоти та форми коливань дозволяє 17% точніше визначати місця максимальних напружень між кріпленнями та одночасно зменшити вплив віброакустичний вплив трубопроводів на результат вимірювання амплитудно-частотних характеристик апарату.
Після розроблення і виготовлення дослідних зразків багатофункціонального віброчастотного давача для вимірювання густини, в’язкості, зусилля (тиску) з циліндричним резонатором було проведено серію експериментів для визначення густини та зусилля з використанням двіброчастотного методу методу Результати експериментів показали покращені метрологічні характеристики ЗВТ та дієвість методу. Результати проведених теоретичних і експериментальних досліджень впроваджено у практику таких підприємств і організацій: ТОВ «Укртехавіа» (Павлоград, Україна), «ММС Інтернешнл Белград» (Белград, Республіка Сербія); ВАТ «РПК «АДМІРАЛ»» (Дніпро, Україна), навчальний процесс Українського державного хіміко-технологічного університету, Дніпровського державного аграрно-економічного університету.Dissertation for the degree of Doctor of Sciences (Technology), Specialty 05.11.13 – «Instruments and Methods of Control and compounds` composition determination». ‒ State Higher Educational Institution «Ukrainian State Chemical Technology University» of the Ministry of Education and Science of Ukraine, Dnipro, 2019. ‒ National Technical University «Kharkiv Polytechnic Institute» of the Ministry of Education and Science of Ukraine. The dissertation is devoted to solving the scientific and applied problem of increasing the reliability of the control of technological parameters (density, viscosity, force (pressure)) in a production environment through the development of new mathematical models and methods for determining technological parameters from the amplitude-frequency characteristics of the oscillatory environment of apparatuses, the use of new multiparameter vibration frequency converters with a universal characteristic and variable signal-to-noise ratio, as well as software development STV filtering noisy measurement information with unknown distribution laws. A vibrational frequency method has been developed for monitoring and measuring the density, viscosity, force (pressure) of gas-liquid media under industrial conditions using a measuring transducer with a tubular, cylindrical resonator, mathematical models of the amplitude-frequency characteristics of technological parameters in devices of various designs are obtained. Theoretical foundations have been developed for the design of non-metallic tubular flow resonators with a wide scope. A multifunctional vibration frequency converter has been developed for measuring density, viscosity, force (pressure) with a cylindrical resonator, which has a universal characteristic. Research work on the identification of distribution laws has been completed, an Kalman filtering algorithm has been developed for measuring information with increased noise, and the structure of a multidimensional control system for technological parameters with a system for diagnosing the shape of resonator vibrations; improved device for identifying the active state of the operator. Implementation of engineering developments of the thesis was carried out at the leading enterprises of the Dnieper and abroad.