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The main goal of this diploma thesis will be realization of tunable frequency filters using voltage conveyors, that are only little explored yet. At the beginnig of diploma thesis the frequency filters and their types will be defined. The theory of voltage conveyors based on principle of duality results from the character of current conveyors. Accordingly these active components will be closely presented. At first there will be defined individual types of voltage conveyors and their closer characteristics. Then design methods of frequency filters using unconventional active components will be described. There will be defined the method of the total admitance net, subsequently design using synthetic components and at the end there will be presented method using follow graphs that will be used to design concrete circuit solution. Using follow graphs method will be found circuit solutions of current structures with unconventional active components. During searching circuit solutions will be very important the posibility to operate the quality factor. That can be obtained by two ways. One way is the activ operation which is done by coeficients of the activ component. Other way is operating using the passiv component. There are found 26 circuits that realize condition of active operating using two active and four passive components. One of these circuits will be chosen and simulated in simulation program PSpice. To compare both methods of operation there will be compiled some circuit with passive operating with two active and five passive components and one of the passive components will be able to operate the quality factor. This circuit will be simulated in the simulation program PSpice again. The circuit will be real compiled and experimentaly measured in laboratory. Results of this measurement will be compared with calculated values and with values acquired from the simulations.

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The main focus of this dissertation is to characterize and improve the performance of thin-film piezoelectric-on-substrate (TPoS) lateral-mode resonators and filters. TPoS is a class of piezoelectric MEMS devices which benefits from the high coupling coefficient of the piezoelectric transduction mechanism while taking advantage of superior acoustic properties of a substrate. The use of lateral-mode TPoS designs allows for fabrication of dispersed-frequency filters on a single substrate, thus significantly reducing the size and manufacturing cost of devices. TPoS filters also offer a lower temperature coefficient of frequency, and better power handling capability compared to rival technologies all in a very small footprint. Design and fabrication process of the TPoS devices is discussed. Both silicon and diamond substrates are utilized for fabrication of TPoS devices and results are compared. Specifically, the superior acoustic properties of nanocrystalline diamond in scaling the frequency and energy density of the resonators is highlighted in comparison with silicon. The performance of TPoS devices in a variety of applications is reported. These applications include lateral-mode TPoS filters with record low IL values (as low as 2dB) and fractional bandwidth up to 1%, impedance transformers, very low phase noise oscillators, and passive wireless temperature sensors.

Au cours de ces dernières années, les chercheurs ont démontré l’importance de l’accordabilité dans les systèmes de télécommunications fonctionnant pour des multiples bandes de fréquences, afin de réduire leur complexité et leur coût. Ce travail se focalise sur des filtres innovants accordables optiquement et propose ainsi une solution alternative aux méthodes plus classiques comme les MEMS ou les diodes. Cette thèse retrace la conception de trois résonateurs pouvant être de bons candidats à intégrer dans le système accordable optiquement développé au travers du manuscrit. Ces éléments sont conçus par le biais de différentes technologies comme : la technologie « Substrate Integrated Waveguide » combinée avec un effet dit métamatériau et la méthode de cavité chargée par un plot capacitif. Tous ces résonateurs ont été créés dans le but d’avoir des performances intéressantes pour trois critères : le facteur de qualité à vide (Q0), la plage d’accord (TR) et la taille. La dernière partie, quant à elle, se consacre au système d’accordabilité basé sur l’utilisation de capacité CMS et de switches RF contrôlés optiquement et fabriqués à l’aide de la technologie silicium CMOS. Plusieurs méthodes ont été utilisées afin d’améliorer les pertes d’insertion des switches RF et par conséquent les performances du système global, démontrant la faisabilité de ce concept innovant accordable optiquement. / Researchers have demonstrated over the last decade the importance of tunability to reduce the complexity and the cost of telecommunication systems operating at multiple frequency bands and standards. This work focuses on novel optically tunable filters for microwave applications and therefore proposes alternative solution to commonly used tuning methods such as MEMS or diodes. The thesis has investigated different resonators for having good candidates for the novel optically tunable system developed throughout this manuscript. Different technologies are used to design such components, namely: Substrate Integrated Waveguide (SIW) technology combined with metamaterial effect and cavity loading. All manufactured resonators are designed to be balanced between three features: the unloaded quality factor (Q0), the tuning range (TR) and the size. The last part deals with the tuning system based on SMT capacitance and optically controlled RF switches based on Si CMOS technology. Several methods have been used to improve the insertion loss of manufactured switches and therefore the performance of the whole system, demonstrating the feasibility of this novel optically based tunable concept.

Les microrésonateurs à mode de galerie passifs à base de cristal ou de verre fabriqués par la méthode de fusion possèdent un facteur de qualité limité à quelques 10E8. Ceci est généralement dû à la contamination de la surface du résonateur lors de sa fusion. Dans ces travaux, nous proposons de contourner cette limitation en utilisant des microrésonateurs actifs pour compenser les pertes. Afin de caractériser les microrésonateurs actifs de très haut facteur de qualité ainsi obtenu, nous nous appuyons sur la méthode CRDM (Cavity Ring Down Measurement). Cette méthode interférométrique est d'une part bien adaptée à la caractérisation de résonateurs de très haut facteur de qualité et d'autre part elle permet de remonter de manière univoque aux facteurs de qualité intrinsèque Qo et extrinsèque Qe du résonateur. Dans un régime de compensation de pertes, nous avons pu atteindre tous les régimes de couplage et obtenus des facteurs de qualité intrinsèques excédant les 10E10. En régime d'amplification sélective, nous avons démontré expérimentalement que l'on pouvait obtenir des gains élevés allant jusqu'à 33 dB et des retards de groupe excédant 2,3 µs dans ces microrésonateurs actifs. Ces microrésonateurs de très haut facteur de qualité et de très haute finesse peuvent présenter un couplage modal se manifestant par un doublet de résonances. Une confrontation théorie/expérience avec la méthode CRDM permet de mesurer un écart très faible entre les doublets. Par ailleurs, ces microrésonateurs présentant un fort confinement spatial et une forte surtension, sont propices à l'observation d'effets non-linéaires. Une modélisation intégrant l'effet thermique et l'effet Kerr a été réalisée. Une confrontation théorie/expérience nous a permis d'estimer la puissance réellement injectée dans le mode ainsi qu'à estimer le volume du mode. / Glass-based whispering gallery mode (WGM) microresonators are easy to produce by melting techniques. However, they suffer from surface contamination which limits their long term quality factor to only about 10E8. In this thesis, we show that an optical gain provided by erbium ions can compensate for residual losses. The optical characterization method is based on frequency-swept “Cavity-Ring-Down-Measurement”. This method can fully describe the linear properties of microcavities such as coupling regime and group delay. In compensation loss regime we demonstrate that it is possible to control the coupling regime of an ultrahigh Q-factor microresonator from undercoupling to spectral selective amplification. Under the selective amplification regime, we obtain an internal Q-factor exceding 10E10. In selective amplification, we experimentally show that it is possible to obtain high amplification up to 33 dB and a high group delay. The microresonators with high Q-factor and high finesse could give rise to a modal coupling which exhibits a splitting of the resonance in the transmission. A characterization of this phenomenon with the cavity ring down method was realized. Moreover, these microresonators, are conducive to the non-linear effect observation. A model incorporating the thermal effect and the Kerr effect has been achieved. Confrontation between theory and experiment allowed us to estimate the real optical power injected into the mode as well as estimating the mode volume.

The ICRP recommends a radiation weighting factor of one for all low-LET radiation. However, many experimental studies find inconsistencies between low-LET RBE and the ICRP's current radiation weighting factor. Generally, there is evidence that dependence exists between radiation energy and radiation RBE where lower energy radiations tend to have a greater biological effect than higher energy radiation. Specifically, the radiations of tritium and carbon K-shell x-rays have been studied in numerous experiments and the biological effects of both of these radiations are consistently greater than that of Co-60. In this work, the relationship between radiation energy and radiation effect has been investigated with the use of a newly developed double strand break (DSB) yield estimation algorithm. This algorithm makes use of a detailed solenoidal 30 nm DNA chromatin model to describe the radiation-sensitive biological target. In addition to the DNA model, NOREC, an event by event Monte Carlo code, was used in this algorithm to characterize the electron track. As an alternative to the conventional approach of computationally simulating DNA damage by spatial overlay of an electron track on DNA, this algorithm instead focuses on quantifying the distance between ionizations in an electron track and next determining the likelihood that any given ionization pair forms a DSB. The first step of the algorithm involves electron characterization while the second step relies on DNA molecule characterization. By assuming a DSB biological endpoint and determining the DSB yield as a function of electron energy, energy dependent RBE values were estimated for monoenergetic electrons from 10 eV to 1 MeV. Photon RBE values, x-ray RBE values and radionuclide RBE values were also calculated and reported in this work in addition to electron RBE values. Photon RBE values were estimated based upon the electron RBE calculation. Photon RBE values were reported from 1 eV to 10 MeV. In turn, x-ray RBE values were calculated based upon photon values for several tube voltage and filter combinations. Finally, RBE values for over 1000 radionuclides were estimated and reported.

The thesis describes development and application of coupled resonant coil sensors, which is of growing interest for remote monitoring applications. An interrogation technique, which improves the accuracy and interrogation range of coupled resonant coil sensors, is introduced. The method uses time-domain gating to produce measurements that are dominated by the response of the sensor coil and are immune to surrounding object interference. For application in structural health monitoring a low cost embeddable coupled coil sensor, which is able to monitor the corrosion potential of reinforcement steel is presented. Results of an accelerated corrosion test using the sensor indicate that corrosion potential can be monitored with a resolution less than 10 mV and a sensitivity of 0.76 kHz/mV. The last part describes a coupled-coil pH sensor based on pH electrode potential measurement. A linear response over a 4 to 10 pH dynamic range and 50 kHz/pH sensitivity are achieved with a 0.1 pH resolution and 30 s response time.

The thesis describes development and application of coupled resonant coil sensors, which is of growing interest for remote monitoring applications. An interrogation technique, which improves the accuracy and interrogation range of coupled resonant coil sensors, is introduced. The method uses time-domain gating to produce measurements that are dominated by the response of the sensor coil and are immune to surrounding object interference. For application in structural health monitoring a low cost embeddable coupled coil sensor, which is able to monitor the corrosion potential of reinforcement steel is presented. Results of an accelerated corrosion test using the sensor indicate that corrosion potential can be monitored with a resolution less than 10 mV and a sensitivity of 0.76 kHz/mV. The last part describes a coupled-coil pH sensor based on pH electrode potential measurement. A linear response over a 4 to 10 pH dynamic range and 50 kHz/pH sensitivity are achieved with a 0.1 pH resolution and 30 s response time.

The objective of the work presented in this thesis is to implement high-Q silicon capacitive micromechanical resonators operating in the HF, VHF and UHF frequency bands. Several variations of a fully silicon-based bulk micromachining fabrication process referred to as HARPSS have been developed, characterized and optimized to overcome most of the challenges facing application of such devices as manufacturable electronic components. Several micromechanical structures for implementation of high performance capacitive silicon resonators covering various frequency ranges have been developed under this work. Design criteria and electromechanical modeling of such devices is presented. Under this work, HF and VHF resonators with quality factors in the tens of thousands and RF-compatible equivalent electrical impedances have been implemented successfully. Resonance frequencies in the GHz range with quality factors of a few thousands and lowest motional impedances reported for capacitive resonators to date have been achieved. Several resonator coupling techniques for implementation of higher order resonant systems with possibility of extension to highly selective bandpass filters have been investigated and practically demonstrated. Finally, a wafer-level vacuum sealing technique applicable to such resonators has been developed and its reliability and hermeticity is characterized.