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Integrering av DSP i talförstärkaren MMT-4 / Integration of DSP in speech amplifier MMT-4Fagerqvist, Gustaf January 2010 (has links)
<p>Att ansluta en digital signalprocessor kräver ett omfattande arbete. Innehållet i denna rapport sammanfattar teoretiska metoder för att integrera den digitala signalprocessorn ADAU1701 i talförstärkaren MMT-4, utvecklad av företaget Xena Medical. Arbetet har till största delen bestått i att finna en lämplig DSP och studera dess datamanual för att anpassa den till talförstärkaren.</p><p>Mycket av rapporten sammanfattar beräkningar av komponentvärden och anpassning av ADAU1701 för MMT-4:s behov. ADAU1701 beskrivs utifrån det så kallade <em>selfboot-</em>läget där processorn kan arbeta som fristående processor.</p> / <p>This thesis describes how to integrate a digital signal processor (DSP) in the speech amplifier MMT-4. This is to improve the sound quality and prevent feedback. Much of the task consisted of selecting a suitable DSP design and components to get it work as a standalone processor in MMT-4. Following this report gives the reader an introduction how to design systems with a DSP and a full description of the DSP ADAU1701.</p>
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Nonlinear dynamics of cracked structures for non-destructive evaluationHiwarkar, Vikrant January 2010 (has links)
The power plant and aerospace industries have been facing a huge loss, due to structural failure. The structural failure occurs due to the presence of the crack in it. Hence, it becomes necessary to monitor the structural health under operating condition. Most of the techniques, for structural health monitoring are used for a specific purpose. Some of these techniques require structure dismantling, which is very much expensive and time consuming. So the vibration based structural health monitoring is advantageous, compared to other techniques. Most of the vibration based Structural Health Monitoring (SHM) approaches, use linear vibration theory. But, these linear vibration based procedures, have inherently low sensitivity to crack. Since crack introduces nonlinearities in the system, their merits in damage detection need to be investigated for SHM. In this thesis, the problem is focused on studying nonlinear dynamics of cracked structures for Structural Health Monitoring. For this, simulations and experiments are performed. The new procedure for the simulation is developed using Matlab-Simulink. It uses the numerical approximation for dynamic compliance operators and a nonlinear model of cracks contact faces interaction to study the dynamic behaviour of the cracked bar. Furthermore, the finite element model of the cracked cantilever bar with crack- tip plasticity is developed and the dynamic behaviour of the elasto-plastic bar is studied. Additionally, numerous experiments are performed to study the dynamics of cantilever bar with the fatigue crack in it. The results from Matlab-Simulink simulation shows the distribution of higher harmonics generated along the bar length, as a function of distance from the crack. In finite element simulation, comparison is made between the resonance frequency of cracked cantilever bar with and without crack-tip plasticity. It is found that, there is decrease in resonance frequency of the cracked bar with cracked tip plasticity, when compared with the resonance frequency of cracked bar without crack-tip plasticity. This reduction in resonance frequency is due to the crack-induced plasticity near the crack tip which affects the overall stiffness of bar. In experiments, the response is measured at four different points on the cracked cantilever bar at a given resonant frequency of excitation at lower and higher vibration amplitude. For lower vibration amplitude, it is found that the response obtained near the vicinity of the crack shows the presence of higher harmonics of resonant frequency, which disappears in the response obtained far away from the crack. For higher vibration amplitude, it is found that the response obtained near the vicinity of the crack shows the presence of higher harmonics along with the low frequency component. This low frequency component causes modulation, which leads to the generation of side band frequencies near the resonant frequency. The occurrence of low frequency component and side band frequencies is due to the vibro-impact behaviour of crack. The amplitude of these side band frequencies and higher harmonics are reduced in the response obtained far away from the crack. This indicates that crack-induced nonlinearity has a localized effect on the dynamics of bar. It is also observed that the magnitude of low frequency component is proportional to the magnitude of resonant frequency of excitation. This indicates that crack behaves like a signal modulator, detector of low frequency component and amplifier as the magnitude of low frequency component is proportional to the magnitude of resonant frequency excitation. From the Matlab-Simulink simulation and experimental results, it is concluded that crackinduced nonlinearity affects the dynamic behaviour of the cracked bar significantly, which will be effective in structural health monitoring. Keywords: vibro-impact, crack, dynamic compliance, harmonics, modulator, detector, amplifier, crack-tip plasticity, resonance frequency, structural health monitoring.
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Amplificateur de puissance en classe commutée pour application dans un émetteur multiradio à haut rendement / Switchmode power amplifier for high efficiency multiradio transmitterAndia Montes, Luis 05 October 2010 (has links)
Cette thèse porte sur la conception d’un amplificateur de puissance à haut rendement entrant dans une architecture d’émission pour des terminaux mobiles multi-radio fonctionnant dans la bande de fréquences 800MHz – 6 GHz. Une architecture polaire avec codeur d’enveloppe ΣΔ a été validée, pour un fonctionnement multiradio, avec un signal test respectant la norme actuellement la plus contraignante, WiMAX mobile – IEEE 802.16e. Cette validation montre la pertinence, du fait de la nature invariante en amplitude du signal issu de l’architecture, d’avoir recours à un amplificateur à haut rendement en classe commutée. Une topologie novatrice d’amplificateur de puissance (PA) a été développée pour la conception et la fabrication de ce circuit. Le procédé de réalisation du PA en technologie ST CMOS SOI 130 nm est détaillé et les simulations sont validées par une caractérisation complète du PA à l’aide de mesures fréquentielles et temporelles. Mesuré avec un signal sinusoïdal à la fréquence de 3,3 GHz, le PA permet d’obtenir une puissance de sortie de +23 dBm avec un rendement en puissance ajoutée de 61% et un gain en puissance de 14 dB. Conçu et réalisé en technologie compatible CMOS, ce PA permet d’envisager une solution type SoC pour l’ensemble de l’architecture / Evolution on demand for circuits for mobile radio transceivers pushes semiconductors industry to increasing integration levels. These constraints, added to those generated by the growing number of current and future generation wireless transmission systems that must coexist into a handheld device have turned multi-standard systems solution obsolete ; parallelizing functional blocs is no more an efficient solution. Reconfigurable multi-radio concept is a major evolution of last systems, offering high power consumption and circuit surface efficiency. This manuscript resumes our research work on multi-radio mobile emitter architectures for the frequency band going from 800 to 6000 MHz and the power amplifier associated with it. A polar architecture which includes a ΣΔ envelope modulator had been validated for multiradio design using à test signal synthesized under the most stringent of current wireless standards; IEEE 802.16e – mobile WiMAX. Validation shows pertinence, up to the non variable amplitude nature of the signal issued of the architecture, of employing a non linear and high efficient power amplifier. An innovative power amplifier topology has been adopted for its design and realization. PA design and realization procedure using 130 nm ST CMOS SOI process has been detailed and validated under PLS simulations and a complete characterization of the PA by frequency and temporal measurements. Characterized under à sine continuous waveform of frequency 3.7 GHz, the PA output power level reaches +23 dBm with a power added efficiency of 61% and a power gain of 14 dB. Designed and realized on fully CMOS compatible technology, this PA facilitates future SoC solutions for architecture plus PA circuits
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Power amplifier design for 5G applications in 28nm FD-SOI technology / Développement d’un amplificateur de puissance pour des applications 5G en technologie 28nm FD-SOITorres, Florent 18 May 2018 (has links)
Le futur réseau mobile 5G est prévu pour être déployé à partir de 2020, dans un contexte d’évolution exponentielle du marché de la téléphonie mobile et du volume de données échangées. La 5G servira de levier à des applications révolutionnaires qui permettront l’émergence du monde connecté. Dans ce but, plusieurs spécifications pour le réseau sont attendues même si aucun standard n’est encore défini et notamment une faible latence, une consommation d’énergie réduite et un haut débit de données. Les bandes de fréquences traditionnellement utilisées dans les réseaux mobiles ne permettront pas d’atteindre les performances visées et plusieurs bandes de fréquences millimétriques sont à l’étude pour créer un spectre complémentaire. Cependant, ces bandes de fréquence millimétriques souffrent d’une forte atténuation dans l’air et dans les matériaux de construction. Plusieurs techniques vont être implémentées pour outrepasser ces limitations dans les zones urbaines denses comme le backhauling, FD-MIMO et beamforming phased array. Ces techniques entraînent l’utilisation d’un grand nombre de transmetteurs dans les stations de bases et dans les dispositifs de l’utilisateur final. La technologie CMOS offre d’indéniables avantages pour ce marché de masse tandis que la technologie FD-SOI offre des performances et fonctionnalités additionnelles. L’amplificateur de puissance est le bloc le plus critique à concevoir dans un transmetteur et consomme le plus d’énergie. Afin d’adresser les challenges de la 5G, plusieurs spécifications concernant la puissance consommée, la linéarité et le rendement sont attendues. Les variations de l’environnement dans les beamforming phased array et le contexte industriel nécessitent des topologies robustes alors qu’une reconfigurabilité au niveau de l’amplificateur de puissance est bénéfique dans le cas de circuits adaptatifs. Cette thèse adresse ces challenges en explorant la conception d’un amplificateur de puissance reconfigurable et robuste pour des applications 5G en intégrant des techniques de design spécifiques et en mettant en avant les avantages de la technologie 28nm FD-SOI pour la reconfigurabilité. / The 5G future mobile network is planned to be deployed from 2020, in a context of exponential mobile market and exchanged data volume evolution. The 5G will leverage revolutionary applications for the advent of the connected world. For this purpose, several network specifications are expected notably low latency, reduced power consumption and high data-rates even if no standard is yet defined. The frequency bands traditionally used for mobile networks will not permit the needed performances and several mmW frequency bands are under study to create a complementary frequency spectrum. However, these mmW frequency bands suffer from large attenuation inbuilding material and in free-space. Therefore, several techniques will be implemented to tackle these limitations indense urban areas like backhauling, FD-MIMO and beamforming phased array. This is leading to a large number of transceivers for base stations and end-user devices. CMOS technology offers undeniable advantages for this mass market while FD-SOI technology offers additional features and performances. The power amplifier is the most critical block to design in a transceiver and is also the most power consuming. To address the 5G challenges, several specifications concerning power consumption, linearity and efficiency are expected. The environment variations inbeamforming phased array and the industrial context drive the need for robust topologies while power amplifier reconfigurability is benefic in a context of adaptive circuits. This thesis addresses these challenges by exploring the conception of a robust and reconfigurable power amplifier targeting 5G applications while integrating specific design techniques and taking advantage of 28nm FD-SOI CMOS technology features for reconfigurability purposes.
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Conception de circuits intégrés radiofréquences reconfigurables en technologie FD-SOI pour application IoT / Design of tunable radiofrequency blocks in FD-SOI technology for IoT applicationsDesèvedavy, Jennifer 08 October 2018 (has links)
La pénétration importante d’objets communicants dans notre vie quotidienne révèle des défis important quant à leur développement. Notamment l’explosion d'applications multimédia sans fil pour l'électronique grand public fait de la consommation électrique une métrique clef dans la conception des dispositifs portables multimodes sans fil. Les émetteurs-récepteurs conventionnels proposent des performances fixes et sont conçus pour respecter ces hautes performances dans toutes les conditions de communication sans fil. Cependant, la plupart du temps, le canal n'est pas dans le pire cas de communication et ces émetteurs-récepteurs sont donc surdimensionnés. En connaissant l’état du canal en temps réel, de tels dispositifs pourraient s'adapter aux besoins et réduire significativement leur consommation électrique. Le défi consiste à respecter la Qualité de Service , ou Quality of Service (QoS) en anglais, imposée par les différents standards de communication. Afin de rester compétitifs, les émetteurs-récepteurs adaptatifs doivent donc proposer une même QoS que ceux déjà disponibles sur le marché. Ainsi, ni la portée de communication ni le temps de réponse ne peuvent être dégradés.Basé sur ces exigences, cette thèse propose une technique d'adaptation pour la conception d'un récepteur reconfigurable qui fonctionne à la limite des performances nécessaires pour recevoir le signal utile. Ainsi, le récepteur proposé est toujours au minimum de consommation électrique tout en garantissant la bonne QoS. Ceci permet alors de multiplier la durée de vie de sa batterie par un facteur 5.Cette adaptabilité est démontrée ensuite côté circuit par la conception d'un LNA (Amplificateur Faible Bruit) dont les performances sont reconfigurables. En effet, en tant que premier élément de la chaîne de réception, le LNA limite le récepteur en termes de sensibilité. Ces travaux exploitent la technologie FD-SOI (Fully Depleted Silicon-On-Insulator) pour d’une part, réduire la consommation du LNA et d’autre part, ajouter de la reconfigurabilité à ce même circuit. / Communicating objects are inviting themselves into daily life leading to digitization of the physical world. This explosion of multimedia wireless applications for consumer electronics makes the power consumption a key metric in the design of multi-mode wireless portable devices. Conventional transceivers have fixed performances and are designed to meet high performances in all wireless link conditions. However, most of the time, the channel of communication is not at worst case and these transceivers are therefore over specified. Being aware of the channel link conditions would allow such devices to adapt themselves and to reduce significantly their power consumption. Therefore, the challenge is to propose a QoS (Quality of Service) in terms of communication range, response time as instance, equivalent to industrial modules with a reduced overall power consumption.To address this purpose, this thesis proposes a design strategy for the implementation of adaptive radio-frequency receiver (Rx) modules. Hence the Rx front end achieves the correct QoS for various scenarii of communications with a minimum of power consumption.As a proof of concept, the adaptive approach is demonstrated with the design of a tunable LNA (Low Noise Amplifier). As the first element of the receiver chain, the LNA limits the receiver in terms of sensitivity and is therefore a good candidate to perform reconfiguration. The body biasing of the FD-SOI (Fully Depleted Silicon-On-Insulator) technology is first exploited to reduce the power consumption of a circuit and then as an opportunity to perform circuit tunability.
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Projeto de osciladores de microondas distribuídos com realimentação reversa. / Design of distributed microwave oscillators with reverse feedback.Barros, Alexandre Della Santa 27 September 2005 (has links)
Esta dissertação propõe uma metodologia de projeto de osciladores distribuídos controlados por tensão - DVCO - com realimentação reversa em freqüência de microondas. Estes constituem uma nova classe de osciladores recentemente proposta, a qual é obtida através da realimentação reversa de amplificadores distribuídos e tem como principal vantagem a possibilidade de sintonia em faixa ultra-larga de freqüência. São apresentados os fundamentos teóricos de operação do circuito e é proposta uma extensão da análise linear apresentada na literatura, considerando linhas de transmissão artificiais m-derivadas, a qual permite prever as transcondutâncias mínimas necessárias dos transistores e a freqüência inicial de oscilação. O método de projeto proposto é direcionado a DVCOs com realimentação reversa empregando transistores de efeito de campo dos tipos MESFET (Metal Semiconductor Field Effect Transistor) e PHEMT (Pseudomorfic High Electron Mobility Transistor), bem como ao uso de tecnologia de circuitos híbridos de microondas - MICs, e circuitos integrados monolíticos de microondas - MMICs. A metodologia proposta definiu critérios para implementar a topologia deste circuito através de componentes reais, considerando-se os parasitas associados aos mesmos. Para validação do procedimento de projeto, concebeu-se e simulou-se através do programa ADS da Agilent um oscilador intitulado DVCO 3 GHz, cuja faixa de freqüência especificada estende-se de 1 a 3 GHz e a potência mínima de saída especificada é de 10 dBm. Um protótipo foi construído em circuito híbrido e seus resultados experimentais foram comparados aos simulados. A freqüência de oscilação medida foi de 1,04 GHz a 3,05 GHz e a potência obtida esteve entre 9,8 e 14,3 dBm, apresentando boa concordância com as simulações. O ruído de fase foi medido entre 100 kHz e 1 MHz de distância da portadora, observando-se uma inclinação proporcional a 1/f3. Verificou-se que a diminuição da corrente de polarização Ids dos transistores, através da redução de sua tensão de polarização de porta-fonte Vgs, melhorou o ruído de fase. Na condição de polarização de menor ruído de fase, observaram-se valores entre -84 e -93 dBc/Hz a 100 kHz da portadora. / In this dissertation, a design methodology applied to microwave reverse feedback distributed voltage controlled oscillators - DVCO - is proposed. This circuit constitutes a new class of oscillators, obtained from reverse feeding back of the distributed amplifier. The main advantage of this topology is its capacity to achieve ultra-wideband frequency tuning. Circuit theoretical background is presented and an extension of the linear analysis presented in the literature is proposed. It allows predicting transistor minimum transconductances and the oscillation initial frequency, considering m-derived artificial transmission lines. The proposed design method is applicable to reverse feedback DVCOs employing field effect transistors MESFET (Metal Semiconductor Field Effect Transistor) and PHEMT (Pseudomorfic High Electron Mobility Transistor), as well as using MIC (Microwave Integrated Circuits) and MMIC (Monolithic Microwave Integrated Circuits) technology. The proposed methodology defined criterion to employ real components, considering the component parasitics. In order to validate the design method, an oscillator named DVCO 3 GHz was designed and simulated through software Agilent ADS, with specified band from 1 up to 3 GHz and minimum output power of 10 dBm. A prototype was implemented in hybrid circuit technology and the measurements were compared to the simulation results. The measured oscillation frequency varied from 1,04 GHz up to 3,05 GHz and the output power was 9,8 to 14,3 dBm, presenting good agreement with simulations. Phase noise was measured in the range between 100 kHz and 1 MHz shift from carrier; in which it was observed a 1/f3 slope. It was verified that decreasing the transistor bias current Ids through decreasing its gate bias voltage Vgs reduced phase noise. In the biasing condition for lowest phase noise, values between -84 and -93 dBc/Hz at 100 kHz off-set from carrier were measured.
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Monolithic microwave integrated circuit (MMIC) low noise amplifier (LNA) design for radio astronomy applicationsSeyfollahi, Alireza 30 April 2018 (has links)
The presentation highlights research on theory, design, EM
modeling, fabrication, packaging, and measurement of GaAs Monolithic
Microwave Integrated Circuits (MMICs). The goal of this work is to design MMIC LNAs with low noise figure, high gain, and wide bandwidth.
The work aims to develop GaAs MMIC LNAs for the application of RF front-end receivers in radio telescopes. GaAs MMIC technology offers modern radio astronomy attractive solutions based on its advantage in terms of high operational frequency, low noise, excellent repeatability and high integration density. Theoretical investigations are performed,
presenting the formulation and graphical methods, and focusing on a
systematic method to design a low noise amplifier for the best noise,
gain and input/output return loss. Additionally, an EM simulation method is utilized and successfully applied to MMIC designs. The effect of packaging including the wire bond and chassis is critical as the frequency increases. Therefore, it is modeled by full-wave analysis where the measured results verify the reliability of these models. The designed MMICs are validated by measurements of several prototypes,
including three C/X band and one Q band MMIC LNAs. Moreover, comparison
to similar industrial chips demonstrates the superiority of the proposed
structures regarding bandwidth, noise and gain flatness, and making them
suitable for use in radio astronomy receivers. / Graduate / 2020-05-01
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Amplificador óptico híbrido Raman/EDFA com controle automático de ganho para redes DWDM reconfiguráveis / Raman/EDFA hybrid optical amplifier with automatic gain control for reconfigurable DWDM networksOliveira, Juliano Rodrigues Fernandes de 27 May 2014 (has links)
Visando atender a massificação das tecnologias da informação e comunicação (TIC) por meio de um aproveitamento mais eficiente da infra-estrutura de fibras ópticas, as redes ópticas DWDM vem passando por significativa evolução de capacidade, com base no uso de formatos de modulação avançados, para canais operando em taxas de 100 Gb/s e superiores, bem como no emprego de topologias dinâmicas e reconfiguráveis. Estas redes ópticas de nova geração impõe novos requisitos de desempenho aos amplificadores ópticos. Especificamente, as características dinâmicas da rede tornam obrigatório o uso de esquemas de controle que assegurem estrita planicidade espectral de ganho enquanto o emprego de formatos de modulação avançados e de alta ordem requer margens mais estreitas em termos da relação sinal-ruído aceitável para detecção dos sinais recebidos. Neste contexto, esta tese propõe e avalia experimentalmente uma topologia de amplificação óptica híbrida Raman/EDFA, introduzindo um novo esquema de controle automático de ganho e apresentando desempenho superior aos amplificadores atualmente usados em redes DWDM reconfiguráveis. O amplificador óptico híbrido desenvolvido baseia-se em um estágio Raman distribuído contra-propagante, com excelente desempenho de figura de ruído (porém com baixa eficiência de conversão de bombeio em amplificação - PCE) seguido de um estágio EDFA, que assegura alta potência de saída, devido a sua elevada PCE. Ganho espectral plano foi obtido por meio de uma técnica de controle automático de ganho inovadora, baseada na atuação paralela e independente de duas malhas de controle automático de ganho, uma primeira aplicada ao estágio de amplificação Raman visando ganho-alvo variável com baixa variação espectral, enquanto outra malha de controle de ganho visa fornecer ganho alvo fixo ao estágio EDFA, com alta potência de saída. / Seeking to support the massive deployment of information and communication technologies (ICTs) by means of a more efficient usage of the optical fiber infrastructure, DWDM optical networks have been undergoing a significant capacity evolution, by using advanced modulation formats for optical channels operating at data rates of 100 Gb/s and beyond, as well as by employing dynamic and reconfigurable network topologies. These new generation optical networks impose new performance benchmarks on the optical amplifiers. Specifically, the dynamic characteristics of the network make mandatory the deployment of control schemes which assure stringent optical gain spectral flatness while the usage of high-order advanced modulation formats translate into more strict margins of signal-to-noise ratios for the detected signals. In this context, this thesis proposes and experimentally evaluates an hybrid Raman/ EDFA optical amplifier topology, introducing a novel automatic gain control scheme and demonstrating improved performance over the optical amplifiers already in use in DWDM reconfigurable networks. The developed hybrid optical amplifier is based on a distributed counter-propagating Raman stage, displaying excellent noise figure performance (albeit presenting low conversion efficiency - PCE) followed by an EDFA stage, which assures high output power, due to its high PCE. Flat spectral gain was achieved by means of a novel gain control technique, based on the parallel and independently acting of two control schemes, the first applied over the Raman amplifying stage, aiming at a variable target gain and low spectral gain ripple, while the other seeks to attain a fixed target gain at the EDFA, assuring a high output power.
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Design of Tunable Low-Noise Amplifier in 0.13um CMOS Technology for Multistandard RF TransceiversKhlif, Wassim 04 May 2007 (has links)
The global market of mobile and wireless communications is witnessing explosive growth in size as well as radical changes. Third generation (3G) wireless systems have recently been deployed and some are still in the process. 3G wireless systems promise integration of voice and data communications with higher data rates and a superior quality of service compared to second generation systems. Unfortunately, more and more communication standards continue to be developed which ultimately requires specific RF/MW and baseband communication integrated circuits that are designed for functionality and compatibility with a specific type of network. Although communication devices such as cellular phones integrate different services such as voice, Bluetooth, GPS, and WLAN, each service requires its own dedicated radio transceiver which results in high power consumption and larger PCB area usage. With the rapid advances in silicon CMOS integrated circuit technology combined with extensive research, a global solutionswhich aims at introducing a global communication system that encompasses all communication standards appears to be emerging. State of the art CMOS technology not only has the capability of operation in the GHz range, but it also provides the advantage of low cost and high level of integration. These features propel CMOS technology as the ideal candidate for current trends, which currently aim to integrate more RF/MW circuits on the same chip. Armed with such technology ideas such as software radio look more attainable than they ever were in the past. Unfortunately, realizing true software radio for mobile applications still remains a tremendous challenge since it requires a high sampling rate and a wide-bandwidth Analog-to-Digital converter which is extremely power hungry and not suitable for battery operated mobile devices. Another approach to realize a flexible and reconfigurable RF/MW transceiver that could operate in a diverse mobile environment and provides a multiband and multistandard solution. The work presented in this thesis focuses on the design of an integrated and tunable low-noise amplifier as part of software defined radio (SDR).
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Étude, réalisation et applications d’une chaîne amplificatrice laser compacte pour l’allumage de turbomoteursTison, Guillaume 22 April 2013 (has links)
Ce travail porte sur l’étude et la réalisation d’une cellule d’allumage laser pour turbomoteurs. Une étude bibliographique nous a permis d’identifier les caractéristiques nécessaires : des impulsions nanosecondes d’au moins 10mJ. La spécificité de l’application impose de nombreuses contraintes qui ont influencé le choix d’une architecture avec deux étages amplificateurs : un amplificateur fibré suivi d’un amplificateur à base de fibre cristalline. Nous avons développé un code permettant de simuler l’amplification d’une impulsion nanoseconde dans ces milieux et ainsi déterminé les caractéristiques techniquesoptimales de chaque étage amplificateur. Ces résultats ont permis la réalisation d’une chaîne d’allumage et sa caractérisation. Une étude particulière del’amplificateur fibré a permis de maîtriser l’apparition d’effets non-linéaires limitants. Finalement, nous démontrons le potentiel de notre solution laserpar plusieurs campagnes d’allumage sur différents bancs moteurs. / This work deals with the design and the construction of a laser ignitionsystem for turbine engines. A review of the dedicated literature allowed us toidentify the required characteristics : nanosecond pulses with at least 10 mJ ofenergy. Our specific application imposes numerous constraints which directlyinfluenced our choice of two amplifier stages : a fiber amplifier followed by acrystalline-fiber based amplifier. We developped a simulation describing theamplification of nanosecond pulses through these two medias and thus de-termined the optimal technical characteristics of each amplifier stage. Theseresults lead to the realization of an laser ignition system that we completelycharacterised. A specific study of the fiber amplifier allowed us to understandand control the appearance of non-linear limiting phenomena. Eventually, wedemonstrate the capabilities of our solution by several laser-ignition field stu-dies.
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