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Design and Implementation of 2.4 GHz Two-Point Voltage-Controlled Oscillators on a Multilayer LTCC Substrate with Embedded Inductors and CapacitorsLee, Sheng-Feng 24 July 2003 (has links)
In the first, we design and implement a Two -Point Voltage-Controlled Oscillator which applied in Open-Loop and Two-Point Close-Loop Modulation
Bluetooth transmitter and include Hybrid and CMOS RFIC design. Second, we design six LTCC embedded components including inductors and capacitors.
The extraction result via traditional equivalent £kmodel match the simulation and the frequency response of adopted model can accurate to device¡¦s Self-Resonant-Frequency nearby compare with measurement. In the end, we design and implement a LTCC Two-Point Voltage-Controlled Oscillator
module and effective ly reduce the module size.
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Frequency synthesis applications of SiGe BiCMOS processesHorst, Stephen J. 07 November 2011 (has links)
Silicon Germanium BiCMOS technology has been demonstrated as an ideal platform for highly integrated systems requiring both high performance analog and RF circuits as well as large-scale digital functionality. Frequency synthesizers are ideal candidates for this technology because the mixed-signal nature of modern frequency synthesis designs fundamentally requires both digital and analog signal processing. This research targets three areas to improve SiGe frequency synthesizers. A majority of this work focuses on applying SiGe frequency synthesizers to extreme environment applications such as space, where low temperatures and ionizing radiation are significant design issues to contend with. A second focus area involves using SiGe HBTs to minimize noise in frequency synthesizer circuits. Improved low frequency "pink" noise in SiGe HBTs provide a significant advantage over CMOS devices, and frequency synthesis circuits are significantly affected by this type of noise. However, improving thermal "white" noise is also considered. Finally, an analysis of AM-PM distortion is considered for SiGe HBTs. The studies presented focus on identifying the physical mechanisms of observed phenomena, such as single event transients or phase noise characteristics in oscillators. The ultimate goal of this research is to provide a reference of effective design parameters for circuit and system designers seeking to take advantage of the properties of SiGe device physics.
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ARTM CPM Receiver/Demodulator Performance: An UpdateTemple, Kip 10 1900 (has links)
ITC/USA 2013 Conference Proceedings / The Forty-Ninth Annual International Telemetering Conference and Technical Exhibition / October 21-24, 2013 / Bally's Hotel & Convention Center, Las Vegas, NV / Since the waveform was first developed by the Advanced Range Telemetry Program (ARTM) and adopted by the Range Commanders Council Telemetry Group (RCC/TG), receiver/demodulators for the ARTM Continuous Phase Modulation (CPM) waveform have undergone continued development by several hardware vendors to boost performance in terms of phase noise, detection performance, and resynchronization time. These same results were initially presented at the International Telemetry Conference (ITC) 2003 when hardware first became available supporting this waveform, at the time called ARTM Tier II. This paper reexamines the current state of the art performance of ARTM CPM receiver/demodulators available in the marketplace today.
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Advances in Filter Miniaturization and Design/Analysis of RF MEMS Tunable FiltersSekar, Vikram 2011 August 1900 (has links)
The main purpose of this dissertation was to address key issues in the design and analysis of RF/microwave filters for wireless applications. Since RF/microwave filters are one of the bulkiest parts of communication systems, their miniaturization is one of the most important technological challenges for the development of compact
transceivers. In this work, novel miniaturization techniques were investigated for single-band, dual-band, ultra-wideband and tunable bandpass filters. In single-band filters, the use of cross-shaped fractals in half-mode substrate-integrated-waveguide bandpass filters resulted in a 37 percent size reduction. A compact bandpass filter that occupies an area of 0.315 mm2 is implemented in 90-nm CMOS technology for 20 GHz applications. For dual-band filters, using half-mode substrate-integrated-waveguides resulted in a filter that is six times smaller than its full-mode counterpart. For ultra-wideband filters, using slow-wave capacitively-loaded coplanar-waveguides resulted in a filter with improved stopband performance and frequency notch, while being 25 percent smaller in size.
A major part of this work also dealt with the concept of 'hybrid' RF MEMS tunable filters where packaged, off-the-shelf RF MEMS switches were used to implement high-performance tunable filters using substrate-integrated-waveguide technology. These 'hybrid' filters are very easily fabricated compared to current state-of-the-art RF MEMS tunable filters because they do not require a clean-room facility. Both the full-mode and half-mode substrate-integrated waveguide tunable filters reported in this work have the best Q-factors (93 - 132 and 75 - 140, respectively) compared to any 'hybrid' RF MEMS tunable filter reported in current literature. Also, the half-mode substrate-integrated waveguide tunable filter is 2.5 times smaller than its full-mode counterpart while having similar performance.
This dissertation also presented detailed analytical and simulation-based studies of nonlinear noise phenomena induced by Brownian motion in all-pole RF MEMS tunable filters. Two independent mathematical methods are proposed to calculate phase noise in RF MEMS tunable filters: (1) pole-perturbation approach, and (2) admittance-approach. These methods are compared to each other and to harmonic balance noise simulations using the CAD-model of the RF MEMS switch. To account for the switch nonlinearity in the mathematical methods, a nonlinear nodal analysis technique for tunable filters is also presented. In summary, it is shown that output signal-to-noise ratio degradation due to Brownian motion is maximum for low fractional bandwidth, high order and high quality factor RF MEMS tunable filters.
Finally, a self-sustained microwave platform to detect the dielectric constant of organic liquids is presented in this dissertation. The main idea is to use a voltage-
controlled negative-resistance oscillator whose frequency of oscillation varies according to the organic liquid under test. To make the system self-sustained, the oscillator is embedded in a frequency synthesizer system, which is then digitally interfaced to a computer for calculation of dielectric constant. Such a system has potential uses in a variety of applications in medicine, agriculture and pharmaceuticals.
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Αυτορυθμιζόμενοι ηλεκτρονικοί προσαρμοστικοί εξισωτές για σύμφωνα οπτικά τηλεπικοινωνιακά συστήματα και δίκτυαΦωτοπούλου, Αναστασία 04 October 2011 (has links)
Στα οπτικά τηλεπικοινωνιακά συστήματα μεγάλων αποστάσεων το κύριο μέλημα είναι η καταπολέμηση των φαινομένων διάδοσης στις οπτικές ίνες. Από το 2004 και μετά το ενδιαφέρον της ερευνητικής κοινότητας έχει στραφεί προς τα οπτικά τηλεπικοινωνιακά συστήματα με δέκτες σύμφωνης φώρασης, καθώς οι τελευταίοι επιτρέπουν την αντιμετώπιση των φαινομένων διάδοσης με ηλεκτρονικά μέσα. Οι σύμφωνοι δέκτες έχουν κατά πολύ αυξημένη πολυπλοκότητα και κόστος σε σχέση με τους δέκτες άμεσης φώρασης, κάνοντας χρήση επιπλέον διατάξεων όπως laser τοπικού ταλαντωτή και προσαρμοσμένες φωτοδιόδους. Όμως, οι δέκτες σύμφωνης φώρασης διατηρούν όλη την πληροφορία (πλάτος και φάση) κατά τη μετατροπή του σήματος από οπτικό σε ηλεκτρονικό, σε αντίθεση με τους δέκτες άμεσης φώρασης που διατηρούν μόνο την πληροφορία που μεταφέρεται από τη στιγμιαία ισχύ του σήματος. Το μεγάλο αυτό πλεονέκτημα των σύμφωνων δεκτών δίνει τη δυνατότητα της αντιμετώπισης των φαινομένων διάδοσης, όπως ο θόρυβος φάσης που θα αναλυθεί σε αυτήν την εργασία, με χρήση συστημάτων ψηφιακής επεξεργασίας σήματος.
Ο θόρυβος φάσης είναι ένας από τους σημαντικότερους περιοριστικούς παράγοντες της απόδοσης ενός σύμφωνου οπτικού τηλεπικοινωνιακού συστήματος. Η εκτίμηση και η απαλοιφή του αποτελεί πάντα αναγκαίο και θεμελιώδες βήμα της σωστής ανάκτησης των δεδομένων στο δέκτη, αλλά και σημαντικότατο παράγοντα της επιτυχούς σχεδίασης ενός οπτικού τηλεπικοινωνιακού συστήματος. Παραδοσιακά, για τον προσδιορισμό του θορύβου φάσης, χρησιμοποιείται ένα κύκλωμα PLL (Phase Locked Loop). Το κύκλωμα αυτό όμως παρουσιάζει αυξημένη πολυπλοκότητα, όσον αφορά την υλοποίησή του σε hardware. Έτσι, το επιστημονικό ενδιαφέρον έχει στραφεί πια στη χρήση προσαρμοστικών αλγορίθμων προσδιορισμού θορύβου φάσης. Για την εκτίμηση του θορύβου φάσης χρησιμοποιούνται κυρίως τυφλοί προσαρμοστικοί εξισωτές πρόσθιας τροφοδότησης, αλλά έχουν προταθεί στη βιβλιογραφία και εξισωτές με ανατροφοδότηση απόφασης. Στην πράξη όμως, μόνο οι εξισωτές πρόσθιας τροφοδότησης είναι υλοποιήσιμοι σε hardware αφού η ανάδραση στα οπτικά δίκτυα εισάγει σημαντική καθυστέρηση. Στην παρούσα εργασία μελετάμε με προσομοίωση την απόδοση πέντε διαφορετικών προσαρμοστικών αλγορίθμων εκτίμησης του θορύβου φάσης σε σύμφωνα συστήματα δεκαεξαδικής ορθογωνικής διαμόρφωσης πλάτους 16-QAM (Quadrature Amplitude Modulation). Πρόκειται για τον αλγόριθμο του Pfau, τον αλγόριθμο του Fatadin, τον αλγόριθμο ελαχίστων μέσων τετραγώνων (LMS, Least Mean Square), τον κανονικοποιημένο αλγόριθμο ελαχίστων μέσων τετραγώνων (NLMS, Normalized LMS) και τον αλγόριθμο ελαχίστων μέσων τετραγώνων με περιορισμούς (Constrained LMS). / The subject of this Diploma Thesis is the phase noise estimation in long-haul terrestrial coherent optical communications systems, using 16-QAM modulation (Quadrature Amplitude Modulation). Five adaptive equalization algorithms are studied by simulation.
The phase noise is a limiting factor of coherent optical communications systems efficiency. The phase noise etsimation is necessary for the right data recovery at the receiver and for the successful design of a coherent optical communications system. Traditionally, a PLL (Phase Locked Loop) circuit is used for the phase noise estimation. However, the implementation of PLL in hardware show increased complexity. Thus, scientific interest is focused to the adaptive algorithms for the phase noise estimation. Blind adaptive feed forward equalizers are used for the phase noise estimation, while decision feedback equalizers have been also proposed in the literature. In practice, however, only the feed forward equalizers are achievable in hardware since the feedback introduces significant delay in optical networks. In this Diploma Thesis we study, by simulation, the performance of five different adaptive phase noise estimation algorithms in 16-QAM (Quadrature Amplitude Modulation) coherent systems. These algorithms are: the Pfau algorithm , Fatadin algorithm, the Least Mean Square Algorithm (LMS Algorithm), the Normalized LMS (NLMS) and the Constrained LMS.
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An experimental investigation into the validity of Leeson's equation for low phase noise oscillator designVan der Merwe, John 12 1900 (has links)
Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2010. / Thesis presented in partial fulfilment of the requirements for the
degree Master of Science in Engineering at
the University of Stellenbosch / ENGLISH ABSTRACT: In 1966, D.B. Leeson presented his model on phase noise in a letter entitled A
Simple Model of Feedback Oscillator Noise Spectrum. This model usually requires
an additional e ffective noise figure in order to conform with measured results. (This
e ffective noise fi gure has to be determined by means of curve-fi tting Leeson's model
with the measured results.) The model is, however, relatively simple to use, compared
with other more accurate phase noise models that have since been developed
and which can only be solved numerically with the aid of computers. It also gives
great insight regarding component choices during the design process.
Therefore several experiments were conducted in order to determine conditions under
which Leeson's model may be considered valid and accurate. These experiments, as
well as the conclusions drawn from their results, are discussed in this document. / AFRIKAANSE OPSOMMING: In 1966 stel D.B. Leeson sy faseruis model bekend in 'n brief getiteld A Simple
Model of Feedback Oscillator Noise Spectrum. Hierdie model vereis gewoonlik die
gebruik van 'n bykomende e ektiewe ruissyfer, sodat die model ooreenstem met die
gemete resultate. (Hierdie e ektiewe ruissyfer kan slegs bepaal word deur middel van
krommepassings tussen Leeson se model en die gemete resultate.) Die model is egter
relatief eenvoudig om te gebruik in teenstelling met ander, meer akkurate, faseruis
modelle wat sedertdien ontwikkel is en slegs met behulp van rekenaars opgelos kan
word. Dit bied ook onoortre
ike insig ten opsigte van komponent keuses tydens die
ontwerpsproses.
Om hierdie rede is verskeie eksperimente uitgevoer met die doel om toestande te
identi seer waaronder Leeson se model as geldig en akkuraat geag kan word. Hierdie
eksperimente, asook die gevolgtrekkings wat van hul resultate gemaak is, word in
hierdie dokument behandel.
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Phase noise measurementGrobbelaar, Johannes Jacobus 03 1900 (has links)
Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: The objective of the thesis is the development of a phase noise measuring system that makes
use of crosscorrelation and averaging to measure below the system hardware noise floor.
Various phase noise measurement techniques are considered after which the phase demodulation
method is chosen to be implemented. The full development cycle of the hardware is
discussed, as well as the post processing that is performed on the measured phase noise. / AFRIKAANSE OPSOMMING: Die doel van hierdie tesis is die ontwikkeling van ’n faseruis meetstelsel wat gebruik maak
van kruiskorrelasie en vergemiddeling om onder die ruisvloer van die meetstelsel se hardeware
te meet.
Verskeie faseruis meettegnieke word ondersoek en die fase demodulasie metode word gekies
om geïmplementeer te word. Die volle ontwikkelingsiklus van die hardeware word bespreek,
sowel as die naverwerking wat toegepas is op die gemete faseruis.
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Oscillateurs asynchrones en anneau : de la théorie à la pratique / Ring oscillators and asynchronous delay lines : applications to PLLs and "Clock recovery" systemsEl Issati, Oussama 12 September 2011 (has links)
Les oscillateurs sont des blocs qui figurent dans presque tous les circuits. En effet,ils sont utilisés pour générer les signaux de synchronisation (les horloges), les signauxmodulés et démodulés ou récupérer des signaux noyés dans du bruit (détection synchrone).Les caractéristiques de ces oscillateurs dépendent de l'application. Dans le cas des boucles àverrouillage de phase (PLL), il existe de fortes exigences en matière de stabilité et de bruitde phase. En outre, face aux avancées des technologies nanométriques, il est égalementnécessaire de prendre en compte les effets liés à la variabilité des procédés de fabrication.Aujourd'hui, de nombreuses études sont menées sur les oscillateurs asynchrones en anneauqui présentent des caractéristiques bien adaptées à la gestion de la variabilité et qui offrentune structure appropriée pour limiter le bruit de phase. A ce titre, les anneaux asynchronessont considérés comme une solution prometteuse pour générer des horloges.Cette thèse étudie les avantages et les potentiels offerts par les oscillateursasynchrones en anneau. Deux applications principales ont été identifiées. D’une part, cesoscillateurs sont une solution prometteuse pour la génération d’horloges polyphasées àhaute fréquence et à faible bruit de phase. D’autre part, ils constituent une alternativesimple, dans une certaine mesure aux oscillateurs plus conventionnels et aux DLLs, car ilssont programmables en fréquence numériquement et sont susceptibles de fournir lesfonctionnalités d’arrêt de type gated clock de façon native. Plusieurs oscillateurs ont étéconçus, implémentés, fabriqués en technologie CMOS 65 nm de STMicroelectronics et,finalement, caractérisés sous pointes. Ces travaux ont notamment permis de démontrer lapertinence de ces oscillateurs, qui constituent une alternative sérieuse aux très classiquesoscillateurs en anneau à base d’inverseurs. / Oscillators are essential building blocks in many applications. For instance, they arebasic blocks in almost all designs: they are part of PLLs, clock recovery systems andfrequency synthesizers. The design of a low phase-noise multi-phase clock circuitry isespecially crucial when a large number of phases is required. There are plenty of workscovering the design of multiphase clocks. High frequency oscillators can be implementedusing ring structures, relaxation circuits or LC circuits. Ring architectures can easily providemultiple clocks with a small die size. With the advanced nanometric technologies, it is alsorequired to deal with the process variability, stability and phase noise. Today many studiesare oriented to Self-Timed Ring (STR) oscillators which present well-suited characteristicsfor managing process variability and offering an appropriate structure to limit the phasenoise. Therefore, self-timed rings are considered as promising solution for generatingclocks.This thesis studies the benefits and potential offered by Self-Timed Ring oscillators.Two main applications have been identified. On the one hand, these oscillators are apromising solution for the generation of high-frequency multi-phase low phase noise clocks.On the other hand, they are a simple alternative to some extent to the conventionaloscillators and DLLs, because they are digitally programmable. Several oscillators havebeen designed, implemented, manufactured in 65 nm CMOS technology fromSTMicroelectronics, and characterized. This work has demonstrated the relevance of theseoscillators, which are a serious alternative to the conventional ring oscillators based oninverters.
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Projeto de um oscilador controlado por corrente com configuração em anel, tecnologia CMOS e melhoria no ruído de fase /Pereira, Marcos Vinicius Alves. January 2010 (has links)
Orientador: Nobuo Oki / Banca: Carlos Antonio Alves / Banca: Fabiano Fruett / Resumo: Este trabalho apresenta um Oscilador Controlado por Corrente (CCO) com configuração em anel usando tecnologia CMOS, com melhorias na faixa de operação e ruído de fase. O oscilador proposto tem uma faixa de oscilação de 0,0989 GHz a 1,2 GHz com uma corrente de controle com um intervalo de 0,1 mA a 3 mA com uma potência dissipada de 11,8 mW. A arquitetura apresenta uma melhoria na fase de ruído de -7 dBc / Hz em relação a um oscilador em anel de três estágios (VCO), também apresentado neste trabalho. A estrutura proposta é baseada na mudança da entrada de controle do oscilador e também em modificações nas polarizações dos transistor de carga do estágio de atraso. Estas mudanças, além de aumentar a faixa de operação do oscilador e diminuir o efeito do ruído de fase, também reduzem a variação da amplitude do sinal de saída que acontece a medida que a frequência de operação aumenta ou diminui. Simulações realizadas com ambos os osciladores, confirmam os resultados. / Abstract: This dissertation presents a Current Controlled Oscillator (CCO-Current-Controlled Oscillator) at ring configuration using CMOS (Complementary Metal-Oxide-Semiconductor) technology, with improvements in operating range and phase noise. The proposed oscillator has an oscillation range of 98.959 MHz to 1.2 GHz with a current control with a range of 0.1 mA to 3 mA with a power dissipation of 11.8 mW. The architecture shows an improvement in phase noise of -7 dBc / Hz when compared with a ring oscillator in three stages (VCO-Voltage- Controlled Oscillator), also presented in this paper. The proposed structure is in the change of input control and also in the polarizations of the load transistor stage of delay. These changes, in modifications increase the operations range of the oscillator, reduce the phase noise and minimize the amplitude variation of the output signal when the frequency operation increase or decrease. Simulations with both oscillators and their comparisons confirm these results. / Mestre
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Evaluation of MIMO radio channel characteristics from TDM-switched MIMO channel soundingTaparugssanagorn, A. (Attaphongse) 04 December 2007 (has links)
Abstract
The present dissertation deals with the evaluation of multiple-input multiple-output (MIMO) radio channel characteristics from time-division multiplexing (TDM)-switched MIMO channel sounding. The research can be divided into three main areas. First, the impacts of phase noise in TDM-switched MIMO channel sounding on channel capacity are studied. Second, we focus on those impacts on channel parameter estimation using the SAGE algorithm. And in the last part, spatial correlation, channel eigenvalue distribution, and ergodic capacity in realistic environments are analyzed.
The rationale behind the first two areas is that most advanced MIMO radio channel sounders employ the TDM technique, which has significant problems from phase noise of the TX and RX phase locked loop (PLL) oscillators causing measurement errors in terms of estimated channel capacity and parameters. We propose statistical models that reproduce the capacity estimates. The effects of the sounding mode (SM), the length of pseudo-random noise (PN) sequence L of the sounding signal, and the system size are disclosed. The distinctive basis is to consider the impact of the actual phase noise in TDM switched MIMO channel sounding, instead of assuming white Gaussian-type phase noise. In a reality, the short-term phase noise component affecting one measurement cycle of a MIMO system plays an important role in the traditional estimators of the radio channel parameters and capacity. We show that the performance impairment is less than that been under the hypothesis of uncorrelated white Gaussian phase-noises samples. The difference is due to the non-vanishing correlation of phase-noise within the measurement cycle. Two approaches to mitigating the impact of phase noise are proposed. The former is the simple and efficient sliding averaging method, where the signal-to-noise ratio (SNR) of the channel impulse response can be increased. The latter is the choice of SM and L, which is more thorough. In the second part, two approaches to mitigating its impact on channel parameter estimation using the SAGE algorithm are also discussed. Besides the sliding averaging, which in general can increase the SNR, the new SAGE algorithm based channel parameter estimation based on the improved signal model accounting for the phase noise in the measurement device is proposed. Finally, the channel eigenvalue distribution and ergodic capacity based on complex hypergeometric functions and their asymptotic characteristics are analyzed. It is shown that the derived theoretical expressions closely approximate the simulated results of the measured finite-dimensional MIMO channels. The spatial correlation and the eigenvalue statistics in frequency selective channels for single and dual polarized antennas are investigated. This knowledge is useful when different MIMO and beamforming techniques are applied.
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