Dissertations / Theses on the topic 'Digital Signal Analyzer'
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Shi, Xiaodong. "Upgrading liquid metal cleanliness analyzer (LiMCA) with digital signal processing (DSP) technology." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22677.
Full textDigital Signal Processing (DSP) technology has been successfully applied to upgrade the LiMCA system. With this technology, the DSP-based LiMCA system is able to describe each LiMCA transient by a group of seven parameters, and with the help of them, classify it into a certain category. Moreover, it simultaneously counts the classified peaks based on their height and their time of occurrence. (Abstract shortened by UMI.)
Зубков, О. В., І. В. Свид, О. С. Мальцев, and Л. Ф. Сайківська. "In-circuit Signal Analysis in the Development of Digital Devices in Vivado 2018." Thesis, Theoretical and Applied Aspects of Device Development on Microcontrollers and FPGAs, MC&FPGA-2019, 2019. https://doi.org/10.35598/mcfpga.2019.003.
Full textЗубков, О. В., І. В. Свид, О. С. Мальцев, and Л. Ф. Сайківська. "In-circuit Signal Analysis in the Development of Digital Devices in Vivado 2018." Thesis, NURE, MC&FPGA, 2019. https://mcfpga.nure.ua/conf/2019-mcfpga/10-35598-mcfpga-2019-003.
Full textLau, Anthony Kwok. "A digital oscilloscope and spectrum analyzer for anaysis of primate vocalizations : master's research project report." Scholarly Commons, 1989. https://scholarlycommons.pacific.edu/uop_etds/2177.
Full textWhittaker, Philip. "On board signal analysis using novel analogue/digital signal processing techniques on low earth orbit mini/microsatellites." Thesis, University of Surrey, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.343484.
Full textGhent, Jeremy E. "A digital signal processing approach to analyze the effects of multiple reflections between highway noise barriers." Ohio : Ohio University, 2003. http://www.ohiolink.edu/etd/view.cgi?ohiou1175090494.
Full textPous, Nicolas. "Analyse de signaux analogiques/radiofréquences à l'aide de ressources digitales en vue du test." Phd thesis, Université Montpellier II - Sciences et Techniques du Languedoc, 2011. http://tel.archives-ouvertes.fr/tel-00667202.
Full textLê, Nguyên Khoa 1975. "Time-frequency analyses of the hyperbolic kernel and hyperbolic wavelet." Monash University, Dept. of Electrical and Computer Systems Engineering, 2002. http://arrow.monash.edu.au/hdl/1959.1/8299.
Full textLarguier, Laurent. "Analyse de l'impact du bruit de commutation sur les blocs digitaux des circuits intégrés CMOS." Montpellier 2, 2008. http://www.theses.fr/2008MON20191.
Full textRodesten, Stephan. "Program för frekvensanalys." Thesis, Örebro universitet, Institutionen för naturvetenskap och teknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:oru:diva-58157.
Full textThis report will cover the work process behind creating a spectrum analyzer. The reader will be able to read about the chosen method but also the alternative methods. Apart from this the theoretical parts behind every moment will also be covered and compared to potential alternative solutions. The project has been carried out on behalf of KA Automation. The purpose of the project was to create a base for analyzing sound frequencies. The goal was to be able to identify sound properties in the form of frequencies in servo motors in for example water pumps. The idea was to be able to in a later development stage be able to identify when new frequencies have entered the audio profile which might result in the motor to be in need of service. The base is created with the help of C# and the sound library NAudio. From the result one can conclude that this program can analyze sound and display the magnitude of its frequency components and is therefore a suitable base for future development.
Hattay, Jamel. "Wavelet-based lifting structures and blind source separation : applications to digital in-line holography." Rouen, 2016. http://www.theses.fr/2016ROUES016.
Full textThe present thesis is meant to develop specific processes, in the realm of wavelets domain, for certain digital holography applications. We mainly use the so-called blind source separation (BSS) techniques to solve numerous digital holography problems, namely, the twin image suppression, real time coding and transmission of holograms. Firstly, we give a brief introduction to in-line configuration of digital holography in flow measurements: the recording step explanation and the study of two reconstruction approaches that have been used during this thesis. Then, we emphasize the two well known obstacles of digital holograms reconstruction, namely, the determination of the best focus plane and the twin image removal. Secondly, we propose a meticulous scrutiny of the tool, based on the Blind Source Separation (BSS), enhanced by a multiscale decomposition algorithm, which enables the blind separation of convolutively mixed images. The suggested algorithm uses a wavelet-based transformer, called Adaptive Quincunx Lifting Scheme (AQLS), coupled with an appropriate unmixing algorithm. The resulting deconvolution process is made up of three steps. In the first step, the convolutively mixed images are decomposed by AQLS. Then, separation algorithm is applied to the most relevant component to unmix the transformed images. The unmixed images are, thereafter, reconstructed using the inverse of the AQLS transform. In a subsequent part, we adopt the blind source separation technique in the wavelet field domain to solve several problems related to digital holography. In this context, we present two main contributions for digital in-line hologram processing. The first contribution consists in an entropy-based method to retrieve the best focus plane, a crucial issue in digital hologram reconstruction. The second contribution consists in a new approach to remove a common unwanted artifact in holography called the twin image. The latter contribution is based on the blind source separation technique, and the resulting algorithm is made up of two steps: an Adaptive Quincunx Lifting Scheme (AQLS) based on the wavelet packet transform and a statistical unmixing algorithm based on Independent Component Analysis (ICA) tool. The role of the AQLS is to maximize the sparseness of the input holograms. Since the convolutive formalism is retained in digital in-line holography, BSS-based tool is extended and coupled with wavelet-based AQLS to fulfill the deconvolution task. Experimental results confirm that convolutive blind source separation is able to discard the unwanted twin image from digital in-line holograms. The last of this part consists in measuring the thickness of a ring. This ring is obtained from an improved reconstructed image of an hologram containing a vapor bubble created by thermal coupling between a laser pulse and nanoparticles in a droplet of a liquid. The last part introduces the Tele-Holography concept. Once the image of the object is perfectly reconstructed, the next objective is to code and transmit the reconstructed image for an interactive flow of exchange between a given laboratory, where the holograms are recorded, and a distant partner research. We propose the tele-holography process that involves the wavelet transform tool for lossless compression and transmission of digital holograms. The concept of tele-holography is motivated by the fact that the digital holograms are considered as a 2D image yielding the depth information of 3D objects. Besides, we propose a quincunx embedded zero-tree wavelet coder (QEZW) for scalable transmission. Owing to the transmission channel capacity, it reduces drastically the bit rate of the holography transmission flow. A flurry of experimental results carried out on real digital holograms show that the proposed lossless compression process yields a significant improvement in compression ratio and total compressed size. These experimentations reveal the capacities of the proposed coder in terms of real bitrate for progressive transmission
Boire, Jean-Yves. "Recueil et analyse des electrogrammes visuels." Clermont-Ferrand 2, 1987. http://www.theses.fr/1987CLF2E382.
Full textMatthews, Brett Alexander. "Probabilistic modeling of neural data for analysis and synthesis of speech." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/50116.
Full textBourdier, Renaud. "Analyse temps/frequence, filtrage et synthese numeriques de signaux de parole : application au filtrage, a la reduction de bruit et a la restauration d'enregistrements anciens." Le Mans, 1988. http://www.theses.fr/1988LEMA1001.
Full textГриненко, Віталій Вікторович, Виталий Викторович Гриненко, Vitalii Viktorovych Hrynenko, and А. В. Любко. "Багатофункціональний осцилографа-аналізатор з генератором сигналів довільної форми." Thesis, Сумський державний університет, 2015. http://essuir.sumdu.edu.ua/handle/123456789/41239.
Full textLiu, Ming. "Analyse et optimisation du système asiatique de diffusion terrestre et mobile de la télévision numérique." Phd thesis, INSA de Rennes, 2011. http://tel.archives-ouvertes.fr/tel-00662247.
Full textThomazella, Rogério. "Técnicas de processamento digital de sinais de sensor piezelétrico na detecção de vibrações auto-excitadas (chatter) no processo de retificação /." Bauru, 2019. http://hdl.handle.net/11449/182150.
Full textResumo: O chatter corresponde a movimentos instáveis e caóticos no sistema de usinagem, resultando em flutuação das forças de corte e na impressão de ondulações na superficie da peça usinada. É um fenômeno indesejável ao processo de usinagem, especialmente ao processo de retificação, pois a sua ocorrência acentuada resulta em um produto acabado com tolerâncias dimensionais e geométricas fora dos padrões, ou até mesmo em danos irreversíveis, como por exemplo, alteração na dureza, alta rugosidade e queima superficial da peça usinada. Na literatura, poucos trabalhos tratam da análise e monitoramento do chatter com técnicas de processamento digital de sinais, especialmente de aceleração. O objetivo desse trabalho é propor uma nova técnica de processamento digital utilizando os sinais de aceleração baseados no cálculo da STFT - Short Time Fourier Transform (Transformada de Fourier de curta duração) e na estatística Relação de Potência (ROP – ratio of power), com a finalidade de detecção do fenômeno de chatter na retificação tangencial plana com rebolo superabrasivo de nitreto cúbico de boro (CBN) e óxido de alumínio. Para tanto, ensaios de retificação foram realizados em corpos de prova de aço ABNT 1045. Um acelerômetro piezelétrico foi acoplado ao suporte das peças e sinais de aceleração foram coletados à uma frequência de amostragem de 2MHz. Dentre as variáveis de saída, obteve-se a dureza Vickers (HV), rugosidade média (Ra) e a análise microestrutural das peças retificadas. Os sinais d... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Chatter corresponds to unstable and chaotic movements in the machining system, resulting in fluctuation of the cutting forces. It is a serious and undesired physical phenomenon that occurs in the grinding process during parts manufacturing. The intense occurrence of this phenomenon during machining can generate a finished part outside the dimensional and geometric tolerances or even cause irreversible damage, such as: changes to the hardness, high surface roughness, and thermal damages to the ground part. Few vibration signal processing techniques have been proposed for monitoring chatter during grinding. Thus, the objective of this study is to propose and validate a new vibration signal processing technique based on the short-time Fourier transform (STFT) and the ratio of power (ROP) statistic for the detection of chatter during the tangential surface grinding of ABNT 1045 steel with different grinding wheels. Experimental grinding tests were conducted, and the vibration signals were recorded at 2 MHz. The Vickers hardness (HV), roughness (Ra) and metallography of the ground workpiece surfaces were performed. Subsequently, a digital processing technique based on the STFT and ROP was applied to the vibration signals to extract the characteristics of the chatter in the grinding process. The results show that this technique can be used to characterize over time the spectral patterns of a frequency band related to chatter. The observed patterns have a strong relationship with th... (Complete abstract click electronic access below)
Doutor
Hadri, Salah Eddine. "Contribution à la synthèse de structures optimales pour la réalisation des filtres et de régulateurs en précision finie." Vandoeuvre-les-Nancy, INPL, 1996. http://www.theses.fr/1996INPL129N.
Full textAlmansa, Andrés. "Sur quelques problèmes mathématiques en analyse d'images et vision stéréoscopique." Habilitation à diriger des recherches, Université René Descartes - Paris V, 2005. http://tel.archives-ouvertes.fr/tel-00011765.
Full textESPINOLA, Sérgio de Brito. "Análise acústica para classificação de patologias da voz empregando análise de Componentes Principais, Redes Neurais Artificiais e Máquina de vetores de Suporte." Universidade Federal de Campina Grande, 2014. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/123.
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Estima-se que um terço da força de trabalho humana dependa da voz para realização de seus ofícios. Procedimentos médicos avaliam a qualidade vocal do indivíduo sendo os mais usados aqueles baseados na escuta da voz (subjetivo) ou na inspeção das dobras (ou pregas) vocais por exames sofisticados (objetivos, porém invasivos e caros). A análise acústica da voz busca extrair medidas robustas para descrever vários fenômenos associados à produção da fala ou características intrínsecas do ser humano como frequência fundamental, timbre, etc. O presente estudo consiste na caracterização de um modelo de processamento digital de Voz para apoio ao diagnóstico no contexto da construção de sistemas de identificação automatizados de patologias da fala. Para análise da técnica proposta foi utilizada uma base de dados (base KAY) que foi estruturada por especialistas num arranjo de seis grupos de Patologias. A esse, acrescentado também um de vozes “Normal”. Assim, 182 vozes foram escolhidas, as quais dispunham de um catálogo indexado de cerca de 33 descritores, para cada voz, calculados da elocução da vogal \a\ sustentada. Ao selecionar combinações desses descritores – como perturbações em frequência (jitter), em amplitude (shimmer) etc, este estudo encontrou evidências estatísticas e mostrou ser possível: a) Separar vozes normais das patológicas – esperado, b) Separar patologias específicas (Paralisia, Edema de Reinke, Nódulos) com acurácia de 100% (para a grande maioria dessas combinações) e cerca de 92% (para Nódulos contra Reinke); c) Discriminá-las por meio de classificadores (redes neurais artificiais e máquina de vetores de suporte) e reduzir a dimensionalidade e complexidade (quantidade de dados) via técnica de análise de componentes principais (ACP) sobre esses descritores para a separação intra patologias; e d) Testes estatísticos com os grupos locais confirmaram também limiares de indícios de Anormalidade presentes na literatura. A utilização de menor quantidade de descritores – obtida pós ACP (compressão) – mostrou-se também eficiente (mesmas taxas de acurácia).
It is estimated one-third of the work force relies on the use the voice in their jobs. The clinical diagnostic may be performed on voice listening by a specialist (subjective perspective) or through invasive and often not cheaper exams to check vocal structures. The area of Voice Acoustic analyses aims to extract robust measurements to describe several phenomena associated with voice production, or human being particular characteristics like fundamental frequency, timbre, etc. This study consisted of a model characterizing the digital voice processing for support in building automatic systems for the identification of disorders of speech (to aid diagnosis of pathologies). To support this investigation and proposed model, a commercial voice database (KAY base) was used with the endorsement from medical specialists. Derived acoustic analyses of those speech samples data records were presented to professionals for classification and six “severities groups” case-studied were built. After these analyses, one Normal group was added and, at the end, 182 voices have been selected. Their refined audio database contain, among other things, an indexed list of vocal descriptors calculated on the presence of the utterance of the vowel \a\ sustained speech. Statistical evidences were found: a) Difference between pathological groups vocal descriptors to normal (expected); b) It was achieved 100% from true positive, most cases, among Paralysis, Reinke's Edema and Nodules separations; c) from few cases, there were detected minor distinctions: Paralysis, Reinke's Edema, Nodules and Edema (pair comparison) with disordered groups; c) Among Machine Learning Algorithms (artificial neural networks "RN" and support vector machine "SVM"), the technique of Principal Components Analyses (PCA) and main statistics performed, it was found facts to help to structure some automated recognition systems. These Supervised learning methods showed that it could be possible to generate classification predictions (disordered presence) for the response to new data; and d) Inner tests also confirmed literature established reference thresholds. Hence considering suitable combinations of descriptors with two machine learning classifiers, as showed, is sufficient suitable and worthy.
Sargent, Gabriel. "Estimation de la structure de morceaux de musique par analyse multi-critères et contrainte de régularité." Phd thesis, Université Rennes 1, 2013. http://tel.archives-ouvertes.fr/tel-00853737.
Full textMaurandi, Victor. "Algorithmes pour la diagonalisation conjointe de tenseurs sans contrainte unitaire. Application à la séparation MIMO de sources de télécommunications numériques." Thesis, Toulon, 2015. http://www.theses.fr/2015TOUL0009/document.
Full textThis thesis develops joint diagonalization of matrices and third-order tensors methods for MIMO source separation in the field of digital telecommunications. After a state of the art, the motivations and the objectives are presented. Then the joint diagonalisation and the blind source separation issues are defined and a link between both fields is established. Thereafter, five Jacobi-like iterative algorithms based on an LU parameterization are developed. For each of them, we propose to derive the diagonalization matrix by optimizing an inverse criterion. Two ways are investigated : minimizing the criterion in a direct way or assuming that the elements from the considered set are almost diagonal. Regarding the parameters derivation, two strategies are implemented : one consists in estimating each parameter independently, the other consists in the independent derivation of couple of well-chosen parameters. Hence, we propose three algorithms for the joint diagonalization of symmetric complex matrices or hermitian ones. The first one relies on searching for the roots of the criterion derivative, the second one relies on a minor eigenvector research and the last one relies on a gradient descent method enhanced by computation of the optimal adaptation step. In the framework of joint diagonalization of symmetric, INDSCAL or non symmetric third-order tensors, we have developed two algorithms. For each of them, the parameters derivation is done by computing the roots of the considered criterion derivative. We also show the link between the joint diagonalization of a third-order tensor set and the canonical polyadic decomposition of a fourth-order tensor. We confront both methods through numerical simulations. The good behavior of the proposed algorithms is illustrated by means of computing simulations. Finally, they are applied to the source separation of digital telecommunication signals
Postolski, Michal. "Discrete topology and geometry algorithms for quantitative human airway trees analysis based on computed tomography images." Phd thesis, Université Paris-Est, 2013. http://pastel.archives-ouvertes.fr/pastel-00977514.
Full textMartins, Carlos Henrique Nascimento. "Plataforma de processamento de sinais para aplicações em sistemas de potência." Universidade Federal de Juiz de Fora (UFJF), 2011. https://repositorio.ufjf.br/jspui/handle/ufjf/4100.
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Este trabalho tem por objetivo principal apresentar o desenvolvimento de plataformas eletrônicas de processamento de sinais de alto desempenho para monitoramento do sistema elétricos de potência. No trabalho são discutidas arquiteturas de hardware para três aplicações em sistemas de potência: analisador fasorial (Phasor Measurement Unit - PMU), analisador de qualidade de energia elétrica (QEE) e analisador de harmônicos variantes no tempo (AHVT). Além disso são todos os conceitos de eletrônica digital e analógica envolvidos na concepção deste projeto, tomando como base equipamentos de mercado, a literatura pertinente e as normas reguladoras para dispositivos de análise de parâmetros elétricos. No projeto é abordado principalmente a implementação de hardware, que envolve implementação de estruturas de conversão Analógico Digital, filtro anti-aliasing, condicionamento de sinais, processamento e gerenciamento de dados e finalmente meios de comunicação. O hardware foi testado utilizando algoritmos básicos de processamento de sinais sendo apresentado casos reais de monitoramento dos parâmetros do sinal elétrico e uma versão inicial do AHVT.
This work has the aim to present the development of electronic platforms for signal processing for high performance electric power monitoring system. At this work are discussed hardware architectures for three power systems applications: phasor measurement unit (PMU), Power Quality Analyzer (PQ) and Time Varying Harmonic Analyzer (TVHA). Also are explained all features of analog and digital electronics involved in the design of this project, based on commercial devices, the literature and regulatory standards for electrical parameters devices. The project is addressed principally to hardware implementation, which involves implementation of structures such as the Analog to Digital conversion, anti-aliasing filter, signal conditioning, processing and data management and communication. The hardware is tested using basic digital signal algorithms and real cases of parameters monitoring are presented. Furthermore prototype version of the TVHA is presented.
Le, Borgne Yann-Aël. "Learning in wireless sensor networks for energy-efficient environmental monitoring." Doctoral thesis, Universite Libre de Bruxelles, 2009. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210334.
Full textIn environmental monitoring studies, many applications are expected to run unattended for months or years. Sensor nodes are however constrained by limited resources, particularly in terms of energy. Since communication is one order of magnitude more energy-consuming than processing, the design of data collection schemes that limit the amount of transmitted data is therefore recognized as a central issue for wireless sensor networks.
An efficient way to address this challenge is to approximate, by means of mathematical models, the evolution of the measurements taken by sensors over space and/or time. Indeed, whenever a mathematical model may be used in place of the true measurements, significant gains in communications may be obtained by only transmitting the parameters of the model instead of the set of real measurements. Since in most cases there is little or no a priori information about the variations taken by sensor measurements, the models must be identified in an automated manner. This calls for the use of machine learning techniques, which allow to model the variations of future measurements on the basis of past measurements.
This thesis brings two main contributions to the use of learning techniques in a sensor network. First, we propose an approach which combines time series prediction and model selection for reducing the amount of communication. The rationale of this approach, called adaptive model selection, is to let the sensors determine in an automated manner a prediction model that does not only fits their measurements, but that also reduces the amount of transmitted data.
The second main contribution is the design of a distributed approach for modeling sensed data, based on the principal component analysis (PCA). The proposed method allows to transform along a routing tree the measurements taken in such a way that (i) most of the variability in the measurements is retained, and (ii) the network load sustained by sensor nodes is reduced and more evenly distributed, which in turn extends the overall network lifetime. The framework can be seen as a truly distributed approach for the principal component analysis, and finds applications not only for approximated data collection tasks, but also for event detection or recognition tasks.
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Les réseaux de capteurs sans fil forment une nouvelle famille de systèmes informatiques permettant d'observer le monde avec une résolution sans précédent. En particulier, ces systèmes promettent de révolutionner le domaine de l'étude environnementale. Un tel réseau est composé d'un ensemble de capteurs sans fil, ou unités sensorielles, capables de collecter, traiter, et transmettre de l'information. Grâce aux avancées dans les domaines de la microélectronique et des technologies sans fil, ces systèmes sont à la fois peu volumineux et peu coûteux. Ceci permet leurs deploiements dans différents types d'environnements, afin d'observer l'évolution dans le temps et l'espace de quantités physiques telles que la température, l'humidité, la lumière ou le son.
Dans le domaine de l'étude environnementale, les systèmes de prise de mesures doivent souvent fonctionner de manière autonome pendant plusieurs mois ou plusieurs années. Les capteurs sans fil ont cependant des ressources limitées, particulièrement en terme d'énergie. Les communications radios étant d'un ordre de grandeur plus coûteuses en énergie que l'utilisation du processeur, la conception de méthodes de collecte de données limitant la transmission de données est devenue l'un des principaux défis soulevés par cette technologie.
Ce défi peut être abordé de manière efficace par l'utilisation de modèles mathématiques modélisant l'évolution spatiotemporelle des mesures prises par les capteurs. En effet, si un tel modèle peut être utilisé à la place des mesures, d'importants gains en communications peuvent être obtenus en utilisant les paramètres du modèle comme substitut des mesures. Cependant, dans la majorité des cas, peu ou aucune information sur la nature des mesures prises par les capteurs ne sont disponibles, et donc aucun modèle ne peut être a priori défini. Dans ces cas, les techniques issues du domaine de l'apprentissage machine sont particulièrement appropriées. Ces techniques ont pour but de créer ces modèles de façon autonome, en anticipant les mesures à venir sur la base des mesures passées.
Dans cette thèse, deux contributions sont principalement apportées permettant l'applica-tion de techniques d'apprentissage machine dans le domaine des réseaux de capteurs sans fil. Premièrement, nous proposons une approche qui combine la prédiction de série temporelle avec la sélection de modèles afin de réduire la communication. La logique de cette approche, appelée sélection de modèle adaptive, est de permettre aux unités sensorielles de determiner de manière autonome un modèle de prédiction qui anticipe correctement leurs mesures, tout en réduisant l'utilisation de leur radio.
Deuxièmement, nous avons conçu une méthode permettant de modéliser de façon distribuée les mesures collectées, qui se base sur l'analyse en composantes principales (ACP). La méthode permet de transformer les mesures le long d'un arbre de routage, de façon à ce que (i) la majeure partie des variations dans les mesures des capteurs soient conservées, et (ii) la charge réseau soit réduite et mieux distribuée, ce qui permet d'augmenter également la durée de vie du réseau. L'approche proposée permet de véritablement distribuer l'ACP, et peut être utilisée pour des applications impliquant la collecte de données, mais également pour la détection ou la classification d'événements.
Doctorat en Sciences
info:eu-repo/semantics/nonPublished
Yang, Tai-Yi, and 楊泰宜. "Realization of Exponential Signal Analyzer by the Digital Signal Processor." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/38607258884751688928.
Full text義守大學
電機工程學系碩士班
96
This thesis offers a complete method to find the exact parameters of the exponential signal, including frequencies, dampings, amplitudes, and phases. This method composes time-domain method and frequency-domain method, it includes three major steps: frequency-domain interpolated algorithm, gradient method, and quadratic interpolation. In the step one, the time-domain signal is transformed into frequency-domain, and the approach parameters will be found by the frequency-domain interpolated algorithm. A re-established signal which is close to the real one is also done in this step. In the step two, the gradient method modifies the re-established signal three times in time-domain. In the step can efficiently overcome the interference of the non-linear factor and the noise. The iteration in the step three is the quadratic interpolation. It could improve the search efficiency and reduce iteration time. After a few iterations, the method will obtain the exact parameters. This paper accomplishes above theories in an analyzer by the TMS320LF2407 DSP. The analyzer is composed of a sensor, a circuit for voltage conversing, an A/D converter, a keyboard, a LCM, and a DSP. The analyzer has features of real-time analysis, process, and display.
Yu, Zhuizhuan. "Digitally-Assisted Mixed-Signal Wideband Compressive Sensing." Thesis, 2011. http://hdl.handle.net/1969.1/ETD-TAMU-2011-05-9328.
Full textRibeiro, Diogo Carlos Alcobia. "Instrumentation for measurement and characterization of mixed-signal devices." Doctoral thesis, 2018. http://hdl.handle.net/10773/24802.
Full textEste trabalho de doutoramento aborda o desenvolvimento de técnicas de medida e caracterização, usando uma perspetiva de radiofrequência, para dispositivos analógico-digitais. Os dispositivos analógico-digitais são blocos importantes no desenho de novos rádios, com maior velocidade de troca de dados, ou mesmo rádios inteligentes. As ADCs e DACs podem ser consideradas como os dispositivos analógico-digitais mais simples. Neste trabalho vão ser consideradas as ADCs e DACs, bem como dispositivos analógico-digitais mais complexos, ou mesmo cadeias completas de rádio. Uma abordagem baseada na análise de circuitos de micro-ondas, semelhante `a utilizada pelos ‘parâmetros S’, vai ser utilizada para expandir as técnicas de caracterização dos dispositivos analógico-digitais. Este tipo de caracterização comportamental ´e suportada amplamente pelas ferramentas utilizadas durante o desenvolvimento de aparelhos rádio. Esta técnica vai permitir aos engenheiros de RF considerar os efeitos não-ideais deste tipo de dispositivos, de uma forma mais simples. O resultado final deste trabalho poder´a vir a ser utilizado para estabelecer um instrumento capaz de caracterizar dispositivos analógico-digitais simples ou mais complexos, da mesma forma que um VNA é utilizado para dispositivos puramente analógicos.
Programa Doutoral em Engenharia Eletrotécnica