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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

A 26 GHz Phase-Locked Loop Frequency Multiplier in 0.18-um CMOS

Carr, John 25 April 2009 (has links)
This thesis presents the analysis, design and characterization of an integrated high-frequency phase-locked loop (PLL) frequency multiplier. The frequency multiplier is novel in its use of a low multiplication factor of 4 and a fully differential topology for rejection of common mode interference signals. The PLL is composed of a voltage controlled oscillator (VCO), injection-locked frequency divider (ILFD) for the first divide-by-two stage, a static master-slave flip-flop (MSFF) divider for the second divide-by-two stage and a Gilbert cell mixer phase detector (PD). The circuit has been fabricated using a standard CMOS 0.18-um process based on its relatively low cost and ready availability. The PLL frequency multiplier generates an output signal at 26 GHz and is the highest operational frequency PLL in the technology node reported to date. Time domain phase plane analysis is used for prediction of PLL locking range based on initial conditions of phase and frequency offsets. Tracking range of the PLL is limited by the inherent narrow locking range of the ILFD, and is confirmed via experimental results. The performance benefits of the fully differential PLL are experimentally confirmed by the injection of differential- and common-mode interfering signals at the VCO control lines. A comparison of the common- and differential-mode modulation indices reveals that a common mode rejection ratio (CMRR) of greater than 20 dB is possible for carrier offset frequencies of less than 1 MHz. Closed-loop frequency domain transfer functions are used for prediction of the PLL phase noise response, with the PLL being dominated by the reference and VCO phase noise contributions. Regions of dominant phase noise contributions are presented and correlated to the overall PLL phase noise performance. Experimental verifications display good agreement and confirm the usefulness of the techniques for PLL performance prediction. The PLL clock multiplier has an operational output frequency of 26.204 to 26.796 GHz and a maximum output frequency step of 16 MHz. Measured phase noise at 1 MHz offset from the carrier is -103.9 dBc/Hz. The PLL clock multiplier core circuit (VCO/ILFD/MSFF Divider/PD) consumes 186 mW of combined power from 2.8 and 4.3 V DC rails. / Thesis (Ph.D, Electrical & Computer Engineering) -- Queen's University, 2009-04-24 11:31:35.384
62

Contribution à la réalisation d’un oscillateur push-push 80GHz synchronisé par un signal subharmonique pour des applications radars anticollisions

Ameziane El Hassani, Chama 06 May 2010 (has links)
Ce travail de thèse s’inscrit dans le cadre d’un projet Français « VéLo » qui est une collaboration entre l’industriel STMicroelectronics et plusieurs laboratoires dont les laboratoires IMS-bordeaux et LAAS. Le but du projet est de concevoir un prototype de radar anticollision millimétrique. Dans ce travail un synthétiseur de fréquence est implémenté. Ce dernier sera intégré dans la chaine de réception du démonstrateur. Une étude bibliographique des architectures classiques de système de radiocommunication a été réalisée. Des exemples d’architectures rencontrées dans le domaine millimétrique ont été étudiés.L’objet principal de cette thèse est l’étude des oscillateurs synchronisés par injection ILO. L’objectif est de réaliser un oscillateur verrouillé par injection qui sera piloté par un oscillateur de fréquence plus basse possédant des caractéristiques de stabilité et de bruit meilleures.Dans ce travail de thèse, le mécanisme de verrouillage des oscillateurs par injection a été décrit. Un modèle de synchronisation par injection série, basé sur la théorie de Huntoon Weiss et inspiré du travail de Badets réalisé sur les oscillateurs synchrones verrouillés par injection parallèle, est proposé. La théorie établie a permis d’exprimer la plage de synchronisation en fonction de la topologie utilisée et des composants de la structure. La validité de la théorie a été évaluée par la simulation de la structure. Les résultats présentés montrent une bonne concordance entre la simulation et la théorie et permettent de valider le principe de synchronisation par injection. La faisabilité de l’intégration d’un ILO millimétrique synchronisé par l’harmonique d’un signal de référence de fréquence plus basse a été démontrée expérimentalement. Le synthétiseur de fréquence est réalisé en technologie BiCMOS 130nm pour des applications millimétriques de STMicroelectronics. Ce dernier opère dans une plage de 2GHz autour de la fréquence 82,5GHz. Les performances en bruit du synthétiseur sont satisfaisantes. Le bruit de phase de l’ILO recopie celui du signal injecté. Les équipements de mesures utilisés, le bruit de phase de l’oscillateur atteint des valeurs inférieures à -110dBc/Hz à 1MHz de la porteuse. / This thesis is a part of a French project "VELO". The project is collaboration between STMicroelectronics and several laboratories including IMS-Bordeaux and LAAS laboratories. The aim of this project is to achieve a prototype of millimeter anti-collision radar. In this work a frequency synthesizer is implemented. This circuit will be incorporated in the reception chain of the demonstrator. A bibliographical study of classical architecture was completed. Examples of architectures encountered in the millimeter frequency range have been studied. The purpose of this thesis is to study the phenomena of synchronization in oscillators. The objective is to design an injection locked oscillator ILO driven by another oscillator, the second oscillator operates at lower frequency and offers better stability and noise characteristics.In this thesis, the injection locking mechanism of the oscillators has been described. A model of synchronization by series injection is proposed. The model is based on the theory of Huntoon and Weiss and inspired by Badets’ work performed on parallel injection. The theory expresses the synchronized frequency range depending on the used topology and the values of the components. The validity of the theory was evaluated by simulation. The results show good agreement between simulation and theory and validate the principle of synchronization by injection.The feasibility of a millimeter ILO synchronized by the harmonic of a reference signal operating at lower frequency has been demonstrated experimentally. The synthesizer was implemented in BiCMOS technology for 130nm applications millimeter of STMicroelectronics. The oscillator operates at 82.5 GHz and performs a frequency range of 2GHz. The noise performance of the synthesizer is satisfactory. The phase noise of the ILO depends on the reference phase noise, and reaches values of -110dBc/Hz at 1MHz from the carrier frequency.
63

Entwicklung eines integrierten Mikroresonators für die kernmagnetische Resonanzspektroskopie kleinster Probenvolumen

Leidich, Stefan 26 February 2010 (has links)
In der vorliegenden Arbeit wird ein Mikroresonator für die kernmagnetische Resonanzspektroskopie kleinster Probenvolumen entwickelt. Der Resonator besteht aus einem Mikrodetektor und einer elektrisch steuerbaren Kapazität für den Resonanzabgleich. Beide Bauteile sind speziell an die Anforderungen des Messverfahrens angepasst. Der Mikrodetektor, welcher die Funktion der Erregung der Kernspins und die Detektion des Messsignals erfüllt, weist aufgrund seiner besonderen Geometrie ein weitgehend homogenes statisches Magnetfeld im Bereich des Probenvolumens auf. Daraus resultieren eine Verbesserung der spektralen Auflösung und eine Steigerung der Empfindlichkeit. Die elektrisch steuerbare Kapazität weist eine hohe elektrische Güte und eine hohe Spannungsfestigkeit auf, wodurch die Verwendung von hohen Pulsleistungen möglich ist. Der Nachweis der Funktionalität des Systems erfolgt durch die Integration des Mikroresonators in einen Probenkopf, welcher zur Messung von Test- und Referenzsignalen eingesetzt wird. Anhand der Messwerte wird gezeigt, dass die neue Entwicklung eine sehr hohe Empfindlichkeit und eine deutlich höhere spektrale Auflösung als andere Detektorsysteme dieser Art aufweist und somit besonders gut für die Messung von sehr kleinen Probenvolumen geeignet ist. / The thesis describes the development of a micro resonator for nuclear magnetic resonance (NMR) spectroscopy of very small sample volumes. The resonator consists of a microcoil and an electrically adjustable capacitance for resonance tuning. Both components are specially designed for the purpose of NMR. The microcoil excites the nuclear spins and detects the measurement signal. Due to the special cylindrical geometry, the detector provides a very homogenous spatial distribution of the static magnetic field at the location of the sample. This leads to improved spectral resolution and increased sensitivity. The electrically adjustable capacitance provides a high quality factor and high voltage stability. Hence, short excitation pulses with high bandwidth can be applied. The components are integrated into a specially designed probe. The functionality of the system is demonstrated by test and reference measurements. The measurement results verify the high sensitivity and the high spectral resolution. Hence, the system is applicable and well suited for NMR measurements of small sample volumes.

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