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Ridley, Raymond Bryan. "A new small-signal model for current-mode control." access full-text online access from Digital dissertation consortium, 1990. http://libweb.cityu.edu.hk/cgi-bin/er/db/ddcdiss.pl?9116643.
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Ridley, Raymond B. "A new small-signal model for current-mode control." Diss., This resource online, 1990. http://scholar.lib.vt.edu/theses/available/etd-07282008-135124/.
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Taillefer, Christopher. "Analog-to-digital conversion via time-mode signal processing." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=18669.
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Conventional voltage-mode analog-to-digital converters use voltage amplifiers, voltage comparators, and switch capacitor networks to perform their signal processing. When compared to digital circuitry, these analog circuit blocks consume significant power, occupy large silicon areas, and operate at relatively slow data processing speeds. A signal processing methodology is proposed that performs analog-to-digital conversion on voltage signals while implementing all the circuits in a digital CMOS logic style. This methodology, called time-mode signal processing, uses time-difference variables as an intermediate signal between the input voltage and digital output. The resulting silicon devices offer very compact, low power, high-speed, and robust analog-to-digital converter alternatives. There are five main analog-to-digital converter topologies: flash, successiveapproximation, pipeline, delta-sigma, and integrating converters. Each converter topology is presented in the context of the time-mode signal processing methodology. The circuits that implement each time-mode data converter are described and when appropriate system-level, transistor-level, and experimental results are revealed. Three integrated circuits (IC) were fabricated in a 0.18-µm CMOS technology to demonstrate the feasibility of the time-mode ADC methodology. The first IC implemented the time-mode comparator and a time-mode flash ADC. The timemode delta-sigma ADC design was demonstrated in the second IC. Two circuits were implemented in the third IC: a differential-input time-mode delta-sigma ADC and a cyclic (or algorithmic) ADC.Les convertisseurs conventionnels pour changer la tension analogique à une tension numérique emploient les amplificateurs de tension, les comparateurs de tension, et les résaux de condensateur sélectionable pour acquir leur traitement de signal. En comparaison le circuit des modules analogues vis-à-vis le circuit numérique nous constatons une augmentation de puissance, une superficie de silicium moins compacte, et un traitement de données beaucoup plus lent. Une méthodologie est proposée pour le traitement du signal qui établi la conversion analogue à numérique sur les signaux de tension et tout en mettant en oeuvre tous les circuits dans un format numérique de type circuit à semiconducteur oxyde-métal à symétrie complémentaire (CMOS). Cette méthodologie reconnue sur le nom de technique-temporelle donne un traitement de signal par domaine temporel en employant la variance de cadence entre les temps comme un signal intermédiare entre la tension d'entrée et la tension de sortie numérique. Les formats numériques de type circuit semiconducteur nous offrent une alternative en temps convertisseur d'analogue à numérique avec l'avantage d'une unité compact, robuste, un coût de puissance réduit, et une haute-vitesse efficace. Il existe cinq topologies principales dans les convertisseurs analogiques à numérique: flash, approximations successives, pipeline, delta-sigma, convertisseurs intégrés. Dans chacune des topologies mentionnées ci-dessus, le traitement de signal par technique-temporelle est une méthode réconnue. Les circuits employés par chaque convertisseur de donnée par technique temporelle sont décrits lorsque le niveau du système est approprié, le niveau du transitor, et les données expérimentales sont identifiés. Trois circuits intégrés (CI) ont été conçus et fabriqués, avec une technologie de 0,18-µm CMOS pour démontrer la possibilité de la méthodologie du techniquetemporelle convertisseur analogique-numéri
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Guttman, Michael. "Sampled-data IIR filtering via time-mode signal processing." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=86770.
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In this work, the design of sampled-data infinite impulse response filters based on time-mode signal processing circuits is presented. Time-mode signal processing (TMSP), defined as the processing of sampled analog information using time-difference variables, has become one of the more popular emerging technologies in circuit design. As TMSP is still relatively new, there is still much development needed to extend the technology into a general signal-processing tool. In this work, a set of general building block will be introduced that perform the most basic mathematical operations in the time-mode. By arranging these basic structures, higher-order time-mode systems, specifically, time-mode filters, will be realized. Three second-order time-mode filters (low-pass, band-reject, high-pass) are modeled using MATLAB, and simulated in Spectre to verify the design methodology. Finally, a damped integrator and a second-order low-pass time-mode IIR filter are both implemented using discrete components.Dans ce mémoire, la conception de filtres de données-échantillonnées ayant une réponse impulsionnelle infinie basée sur le traitement de signal en mode temporel est présentée. Le traitement de signal dans le domaine temporel (TSDT), définie comme étant le traitement d'information analogique échantillonnée en utilisant des différences de temps comme variables, est devenu une des techniques émergentes de conception de circuits des plus populaires. Puisque le TSDT est toujours relativement récent, il y a encore beaucoup de développements requis pour étendre cette technologie comme un outil de traitement de signal général. Dans cette recherche, un ensemble de blocs d'assemblage capable de réaliser la plupart des opérations mathématiques dans le domaine temporel sera introduit. En arrangeant ces structures élémentaires, des systèmes en mode temporel d'ordre élevé, plus spécifiquement des filtres en mode temporel, seront réalisés. Trois filtres de deuxième ordre dans le domaine temporel (passe-bas, passe-bande et passe-haut) sont modélisés sur MATLAB et simulé sur Spectre afin de vérifier la méthodologie de conception. Finalement, un intégrateur amorti et un filtre passe-bas IIR de deuxième ordre en mode temporel sont implémentés avec des composantes discrètes.
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Tirunagari, Santosh. "Dynamic mode decomposition for computer vision and signal processing." Thesis, University of Surrey, 2017. http://epubs.surrey.ac.uk/813255/.
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The method of Dynamic Mode Decomposition (DMD) was introduced originally in the area of Computatational Fluid Dynamics (CFD) for extracting coherent structures from spatio-temporal complex fluid flow data. DMD takes in time series data and computes a set of modes, each of which is associated with a complex eigenvalue. DMD analysis is closely associated with spectral analysis of the Koopman operator, which provides linear but infinite-dimensional representation of nonlinear dynamical systems. Therefore, by using DMD a nonlinear system could be described by a superposition of modes whose dynamics are governed by the eigenvalues. The key advantage of DMD is its data-driven nature which does not rely on any prior assumptions except the inherent dynamics which are observed over time. Its capability for extracting relevant modes from complex fluid flows has seen significant application across multiple fields, including computer vision, robotics and neuroscience. This thesis, in order to expand DMD to other applications, advances the original formulation so that it can be used to solve novel problems in the fields of signal processing and computer vision. In signal processing this thesis introduces the method of using DMD for decomposing a univariate time series into a number of interpretable elements with different subspaces, such as noise, trends and harmonics. In addition, univariate time series forecasting is shown using DMD. The computer vision part of this thesis focuses on innovative applications pertaining to the areas of medical imaging, biometrics and background modelling. In the area of medical imaging a novel DMD framework is proposed that introduces windowed and reconstruction variants of DMD for quantifying kidney function in Dynamic Contrast Enhanced Magnetic Resonance imaging (DCE-MRI) sequences, through movement correction and functional segmentation of the kidneys. The biometrics portion of this thesis introduces a DMD based classification pipeline for counter spoofing 2D facial videos and static finger vein images. The finger vein counter spoofing makes use of a novel atemporal variant of DMD that captures micro-level artefacts that can differentiate the quality and light reflection properties between a live and a spoofed finger vein image, while the DMD on 2D facial image sequences distinguishes attack specific cues from a live face by capturing complex dynamics of head movements, eye-blinking and lip-movements in a data driven manner. Finally, this thesis proposes a new technique using DMD to obtain a background model of a visual scene in the colour domain. These aspects form the major contributions of this thesis. The results from this thesis present DMD as a promising approach for applications requiring feature extraction including: (i) trends and noise from signals, (ii) micro-level texture descriptor from images, and (iii) coherent structures from image sequences/videos, as well as applications that require suppression of movements from dynamical spatio-temporal image sequences.
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Bhattaram, Sneha. "Signal Compression Methods for a Wear Debris Sensor." University of Akron / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=akron1399201029.
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Ali-Bakhshian, Mohammad. "Digital processing of analog information adopting time-mode signal processing." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=114237.
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As CMOS technologies advance to 22-nm dimensions and below, constructing analog circuits in such advanced processes suffers many limitations, such as reduced signal swings, sensitivity to thermal noise effects, loss of accurate switching functions, to name just a few. Time-Mode Signal Processing (TMSP) is a technique that is believed to be well suited for solving many of these challenges. It can be defined as the detection, storage, and manipulation of sampled analog information using time-mode variables. One of the important advantages of TMSP is the ability to realize analog functions using digital logic structures. This technique has a long history of application in electronics; however, due to lack of some fundamental functions, the use of TM variables has been mostly limited to intermediate stage processing and it has been always associated with voltage/current-to-time and time-to-voltage/current conversion. These conversions necessitate the inclusion of analog blocks that contradict the digital advantage of TMSP. In this thesis, an intensive research has been presented that provides an appropriate foundation for the development of TMSP as a general processing tool. By proposing the new concept of delay interruption, a completely new asynchronous approach for the manipulation of TM variables is suggested. As a direct result of this approach, practical techniques for storage, addition and subtraction of time-mode variables are presented. To Extend the digital implementation of TMSP to a wider range of applications, the comprehensive design of a unity gain dual-path time-to-time integrator (accumulator) is demonstrated. This integrator is then used to implement a digital second-order delta-sigma modulator. Finally, to demonstrate the advantage of TMSP, a very low power and compact tunable interface for capacitive sensors is presented that is composed of a number of delay blocks associated with typical logic gates. All the proposed theories are supported by experimental results and post-layout simulations.The emphasis on the digital construction of the proposed circuits has been the first priority of this thesis. Having the building blocks implemented with a digital structure, provides the feasibility of a simple, synthesizable, and reconfigurable design where affordable circuit calibrations can be adopted to remove the effects of process variations.Les technologies CMOS progressant vers les procédés 22 nm et au delà, la abrication des circuits analogiques dans ces technologies se heurte a de nombreuses limitations. Entre autres limitations on peut citer la réduction d'amplitude des signaux, la sensibilité aux effets du bruit thermique et la perte de fonctions précises de commutation. Le traitement de signal en mode temps (TMSP pour Time-Mode Signal Processing) est une technique que l'on croit être bien adapté pour résoudre un grand nombre de problèmes relatifs a ces limitations. TMSP peut être défini comme la détection, le stockage et la manipulation de l'information analogique échantillonnée en utilisant des quantités de temps comme variables. L'un des avantages importants de TMSP est la capacité à réaliser des fonctions analogiques en utilisant des structures logiques digitales. Cette technique a une longue histoire en terme d'application en électronique. Cependant, en raison du manque de certaines fonctions fondamentales, l'utilisation de variables en mode temps a été limitée à une utilisation comme étape intermédiaire dans le traitement d'un signal et toujours dans le contexte d'une conversion tension/courant-temps et temps-tension/courant. Ces conversions nécessitent l'inclusion de blocs analogiques qui vont a l'encontre de l'avantage numérique des TMSP. Cette thèse fournit un fondement approprié pour le développement de TMSP comme outil général de traitement de signal. En proposant le concept nouveau d'interruption de retard, une toute nouvelle approche asynchrone pour la manipulation de variables en mode temps est suggéré. Comme conséquence directe de cette approche, des techniques pratiques pour le stockage, l'addition et la soustraction de variables en mode temps sont présentées. Pour étendre l'implémentation digitale de TMSP à une large gamme d'applications, la conception d'un intégrateur (accumulateur) à double voie temps- à -temps est démontrée. cet intégrateur est ensuite utilisé pour implémenter un modulateur delta-sigma de second ordre.Enfin, pour démontrer l'avantage de TMSP, une Interface de très basse puissance, compacte et réglable pour capteurs capacitifs est présenté. Cette interface est composé d'un certain nombre de blocs de retard associés à des portes logiques typiques. Toutes les théories proposées sont soutenues par des résultats expérimentaux et des simulations post-layout. L'implémentation digitale des circuits proposés a été la première priorité de cette thèse. En effet, une implémentation des bloc avec des structures digitales permet des conceptions simples, synthétisable et reconfigurables où des circuits de calibration très abordables peuvent être adoptées pour éliminer les effets des variations de process.
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Bi, G. "Application of mode controlled logic to pipelined serial signal processing]." Thesis, University of Essex, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381239.
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Bergogne, Christian. "Transmission en mode paquet à faible rapport signal à bruit /." Paris : École nationale supérieure des télécommunications, 1997. http://catalogue.bnf.fr/ark:/12148/cb36165913n.
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Holzner, Jürgen. "Signal theory and processing for Burst-mode and ScanSAR interferometry." Thesis, University of Edinburgh, 2003. http://hdl.handle.net/1842/23054.
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ScanSAR data provides wide swath coverage and at fast revisit times at the expense of resolution. Moreover, the ENVISAT/ASAR alternating polarisation mode uses the burst-mode acquisition to map the scene quasi-parallel in two polarisations. Both modes are also attractive for interferometric applications, e.g. efficient topographic mapping of large areas and monitoring of large scale motions. A single-pass ScanSAR interferometer was flown during the 11-day Shuttle Radar Topographic Mission (SRTM). Repeat-pass ScanSAR data are routinely available from RADARSAT-1 and ENVISAT/ASAR and the coming RADARSAT-2 and ALOS/PALSAR mission will also provide ScanSAR imaging modes. This thesis provides a complete description of burst-mode and ScanSAR signal characteristics, algorithms for interferometric processing, and options for the efficient utilisation of the wide-swath data. In the course of the examinations the following problems are addressed: Doppler centroid estimation, azimuth scanning pattern synchronisation, common band filtering and resampling in the presence of high squint, beam alignment, and interferogram formation. A new fast time-variant interpolator for burst-mode data is introduced and tested. Several processing options are described that exploit the flexibility of burst-mode and ScanSAR data. Hence, possibilities are available for prototype systems that are most conveniently integrated into existing strip-map processors and for systems that allow data processing in operational fashion. A prototype processor that makes efficient use of the burst-mode and ScanSAR data properties was implemented and tested using a RADARSAT-1 ScanRAR Narrow data set. In this way, RADARSAT-1 repeat-pass ScanSAR interferometry is demonstrated. The generated digital elevation model has quality in the order or better than DTED-1. Moreover, after interferometric processing the ScanSAR interferogram resembles a course resolution strip-map interferogram and, hence, possibly all applications of SAR interferometry may benefit from ScanSAR data. In particular, the data is favourable for those applications gaining from the wide swath extend, the fast revisit times, or from the increase in information provided with the alternating polarisation mode, as on ENVISAT/ASAR.
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Bai, Neng. "Mode-Division Multiplexed Transmission in Few-mode Fibers." Doctoral diss., University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5761.
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As a promising candidate to break the single-mode fiber capacity limit, mode-division multiplexing (MDM) explores the spatial dimension to increase transmission capacity in fiber-optic communication. Two linear impairments, namely loss and multimode interference, present fundamental challenges to implementing MDM. In this dissertation, techniques to resolve these two issues are presented. To de-multiplex signals subject to multimode interference in MDM, Multiple-Input-Multiple-Output (MIMO) processing using adaptive frequency-domain equalization (FDE) is proposed and investigated. Both simulations and experiments validate that FDE can reduce the algorithmic complexity significantly in comparison with the conventional time-domain equalization (TDE) while achieving similar performance as TDE. To further improve the performance of FDE, two modifications on traditional FDE algorithm are demonstrated. i) normalized adaptive FDE is applied to increase the convergence speed by 5 times; ii) master-slave carrier recovery is proposed to reduce the algorithmic complexity of phase estimation by number of modes. Although FDE can reduce the computational complexity of the MIMO processing, due to large mode group delay (MGD) of FMF link and block processing, the algorithm still requires enormous memory and high hardware complexity. In order to reduce the required tap length (RTL) of the equalizer, differential mode group delay compensated fiber (DMGDC) has been proposed. In this dissertation, the analytical expression for RTL is derived for DMGDC systems under the weak mode coupling assumption. Instead of depending on the overall MGD of the link in DMGD uncompensated (DMGDUC) systems, the RTL of DMGDC systems depend on the MGD of a single DMGDC fiber section. The theoretical and numerical results suggest that by using small compensation step-size, the RTL of DMGDC link can be reduced by 2 orders of magnitude compared to DMGDUC link. To compensate the loss of different modes, multimode EDFAs are presented with re-configurable multimode pumps. By tuning the mode content of the multimode pump, mode-dependent gain (MDG) can be controlled and equalized. A proto-type FM-EDFA which could support 2 LP modes was constructed. The experimental results show that by using high order mode pumps, the modal gain difference can be reduced. By applying both multimode EDFA and equalization techniques, 26.4Tb/s MDM-WDM transmission was successfully demonstrated. A brief summary and several possible future research directions conclude this dissertation.Ph.D.
Doctorate
Optics and Photonics
Optics and Photonics
Optics
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Deng, Zhichao. "Mode locked fiber lasers and their application in microwave signal generation." Thesis, University of Ottawa (Canada), 2005. http://hdl.handle.net/10393/26886.
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An investigation of mode-locked fiber ring lasers and their applications in photonic generation of microwave signals is presented in this thesis. Both passive mode locking and active mode locking are investigated.
For the passive mode-locking, a fiber laser with figure-eight structure that incorporates a nonlinear amplifying loop mirror as a saturable absorber is proposed and demonstrated. One application of the demonstrated passively mode locked fiber ring laser is to generate high-quality microwave signals. In this thesis, a microwave signal generated by beating the mode-locked longitudinal modes at a photodetector is realized. The results show that the generated microwave signal has low phase noise with high stability.
Multiwavelength mode locked laser can find many applications in optical communications. In this thesis, a multiwavelength passively mode-locked fiber ring laser using cascaded fiber Bragg gratings is proposed and demonstrated. It is different from multiwavelength active mode locking in which the round-trip frequencies for all wavelengths must be identical; for passive mode locking, it is demonstrated theoretically and experimentally that the round-trip frequencies are not necessarily identical. A three-wavelength fiber ring laser that is passively mode locked with non-identical round-trip frequencies is demonstrated. (Abstract shortened by UMI.)
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He, Xuan. "MIMO Digital Signal Processing in Few-Mode Fiber Optical Communication Systems." Thesis, University of Louisiana at Lafayette, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3687684.
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Space-division multiplexing (SDM) has been extensively proposed to overcome the next capacity crunch with ever-increasing data and video traffic. Among several SDM approaches, mode-division-multiplexing (MDM) in few-mode fiber (FMF) is the most auspicious technology. One key challenge in FMF transmission systems is random mode coupling among different fiber modes, which can cause severe inter-modal crosstalk. Moreover, large accumulated differential mode group delay (DMGD) can induce significant inter-symbol interference (ISI).
The approach of adaptive multi-input multi-output (MIMO) digital signal processing (DSP) has been proposed and demonstrated to untangle the crosstalk between the spatial modes and compensate the DMGD. In FMF systems, compared with time-domain adaptive MIMO signal processing, the implementation of frequency domain method achieves much lower hardware complexity. In this dissertation, a single-stage adaptive MIMO equalizer is proposed to compensate both DMGD and chromatic dispersion (CD) simultaneously in order to further reduce the hardware complexity.
Except for hardware complexity, the convergence rate of adaptive MIMO equalizer is another essential concern. The adaptive MIMO equalizer with slower convergence speed requires longer training symbols, thus decreasing the system overall efficiency. In the dissertation, two advanced step size control methods are presented to increase the convergence rate of the conventional FD-LMS algorithm. The first approach is the signal power spectral density (PSD) dependent method, which adopts the step size for each frequency bin inverse to its power level in order to converge the estimated equalization error to zero, thus it is the optimal solution in the systems with noise-free channel. The other method is the noise PSD directed method, which adopts the frequency bin-wise step size to render the estimated error converge to the channel background noise, thus it is the optimum solution in the systems with additive white Gaussian noise channel.
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Arihilam, Edwin. "Measurement of electromagnetic noise coupling and signal mode conversion in data cabling." Thesis, De Montfort University, 2018. http://hdl.handle.net/2086/17479.
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Nonuniformity in transmission lines is known to be one of the causes of electromagnetic compatibility (EMC) and signal integrity (SI) issues, especially at high frequencies. This may include unpredictability in the manufacturing process, design constraints, tolerances in the values of terminal components, pigtail effects, etc., that can generate, common mode currents - with resultant degradation of signal performance of transmission lines with respect to ground. All these phenomena are capable of converting the desired differential mode (DM) signal into the unwanted common mode (CM) signal and vice versa. This study looks at cable nonuniformity resulting from irregular cable twists in twisted pair cabling, using the Category 6 UTP as an example, and considers this phenomenon responsible for signal mode conversion. Although twisted pair cables are generally often regarded as balanced transmission lines, the study shows that signal mode conversion is capable of twisted pair cables, and that makes twisted pair cabling a non-ideal balanced transmission line. However, it is difficult to analyse nonuniformity using differential equations because of the changing per-unit-length (p.u.l) parameters throughout an entire line length. Because of this, experimental measurements based on mixed-mode s-parameters analysis are designed and used to show that twisted pair cables can convert a differential mode signal to common mode signal and thus cause radiated emissions to the circuit environment. A vital contribution of this study is in the measurement techniques used. Similarly, a common mode signal (represented by an externally generated noise signal) can couple onto the transmission line, and because of the physical structure of the line, the line could become susceptible to external noise. These phenomena are not associated with ideal balanced transmission lines. In either case, if the mode conversion is not minimized, it has the potential to affect the performance of the twisted pair transmission line in terms of bit error rate. Bit error rate, BER, is basically the average rate at which transmitted errors occur in a communication system due to noise and is defined as the number of bits in error divided by the total number of bits transmitted. Therefore, reducing mode conversion in a transmission line helps to reduce the bit error rate and indeed minimise crosstalk in the communication channel. The experiments were conducted using a 4-Port Vector Network Analyser. The significance of using the 4-port VNA is that it has a general application in cable parameter measurement in the absence of specialized/customized measuring instruments. Nonetheless, with some transmission line assumptions based on the Telegrapher's equation and applying the concept of modal decomposition, the mechanisms of signal mode conversion could be recognised. Consequently, an approximate first step symbolic solution to identifying EM radiation and hence DM-to-CM conversion and vice versa in data cable were proposed.
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Bansen, Justin Andrew. "Evaluation of Traffic Operations at Intersections in Malfunction Flash Mode." Thesis, Georgia Institute of Technology, 2006. http://hdl.handle.net/1853/10551.
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During a signal malfunction, traffic signals are operated in the flash mode. During this event, drivers are presented with one of two possible scenarios: (1) flashing yellow on the major street and flashing red on the minor street or (2) flashing red on all approaches. Yellow/red flash is typically the default mode utilized based on the expectation that red/red flash would produce an intolerable amount of delay. However, little research has been conducted to date on flashing operations, with exception of low-volume nighttime conditions.
A traffic signal malfunction can occur during any time of the day, potentially placing the signal into flash mode under moderate to peak traffic volume conditions. In order to assess the safety implications of these events and improve the process by which the mode of flash (yellow/red versus red/red) is selected, the research contained in this study evaluated driver behavior and the operational characteristics of intersections operating in malfunction flash mode under a wide spectrum of traffic demands.
Analysis of field data collected at thirteen study intersections in the Atlanta, Georgia area found that confusion exists among drivers approaching a signal in flash mode. The analysis found that a significant percentage of vehicles stop on a yellow indication. It was seen that an intersection flashing yellow/red could operate as a two-way stop or four-way stop, potentially transitioning between these two alternatives on a minute-by-minute basis. This creates an increased potential for crashes and further compounds the problem of driver expectancy by creating a constantly changing control environment. The stopping on yellow also introduces additional delay, which reduces the operational benefit of utilizing the yellow/red flash mode. Furthermore, a high level of traffic violations was observed for the flashing red indications for both yellow/red and red/red flashing operation.
Based upon the study results, providing one consistent mode of flashing operation may be a reasonable solution to improving driver expectancy and safety. Red/red flashing operation is the preferred mode as it reduces vehicle speeds and the variability in the number of vehicles stopping, while improving driver expectancy.
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Azadeh, Mohammad. "Current mode processing and architecture for optoelectronically interconnected arrays /." Thesis, Connect to this title online; UW restricted, 2000. http://hdl.handle.net/1773/6104.
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Shahbaz, Askari. "Dual mode brain near infrared spectroscopy and electroencephalography hardware design and signal processing." Thesis, University of British Columbia, 2016. http://hdl.handle.net/2429/58418.
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Wang, Ruonan. "Enhancement/depletion-mode HEMT technology for III-nitride mixed-signal and RF applications /." View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?ECED%202008%20WANG.
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Hua, Thanh Phong. "Adaptation mode controllers for adaptive microphone arrays." Rennes 1, 2006. http://www.theses.fr/2006REN1S136.
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Le traitement d’antenne réalisé par un réseau de microphones permet l’extraction d’un signal cible dans un environnement bruité. Dans ce travail, une calibration automatique est proposée pour supprimer la différence de gain entre les microphones tout en gardant la même puissance moyenne en sortie de l'antenne fixe. Deux nouveaux contrôleurs de mode d'adaptation (AMC pour Adaptation Mode Controller) sont proposés pour la mise à jour des coefficients des filtres suivant la situation détectée (présence de signal cible ou d’interférence). Ces AMC sont basés sur une estimation du rapport signal-à-interférence. Les résultats des évaluations dans un environnement réel montrent que les AMC proposés contribuent à une meilleure qualité du signal de sortie ainsi qu'à une augmentation du taux de reconnaissance vocale pouvant atteindre 31% en comparaison d’un AMC conventionnel. Ces systèmes sont intégrés au robot PaPeRo développé par NEC et destiné à vivre en interaction avec les humains.
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Chuai, Kun. "High order phase-locked loop design and test for time-mode signal processing applications." Thesis, McGill University, 2010. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=95015.
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This thesis first presents a pole-zero placement algorithm for the systematic design of high-order phase-locked loops (PLL) serving as anti-imaging and anti-aliasing filters for time-mode signal processing applications. A 6th order PLL is designed and fabricated on a printed circuit board and is interfaced to a production mixed-signal tester. The correct filtering operation and large-signal transfer characteristic of the PLL are verified with an all-digital DFT solution. The digital test input is driven by a single clock, which can be programmed directly from an ATE high-speed digital pattern generator. As application of these high-order PLLs, an accurate and low-cost clock delay generation system is presented. With proper compensation and calibration, a delay resolution of 15 ps is achieved over an 8.4 ns range. This technique is shown experimentally to be a viable solution for clock alignment and for measuring jitter at a 50 GHz effective sampling rate.Ce mémoire présente tout d'abord une approche systématique descendante pour la conception de boucles à verrouillage de phase (PLL) ayant un ordre arbitraire et opérant comme filtre anti-image ou anti-repliement pour le traitement de signal dans le domaine temporel. Un PLL de 6e ordre a été conçu et fabriqué sur une carte de circuit imprimé montée sur un tester à signaux-mixtes (ATE). La fonction de filtrage et la caractéristique de transfert de grands-signaux sont vérifiées à l'aide d'une solution de conception pour test (DFT) entièrement numérique. Le signal d'entrée numérique est cadencé par une horloge unique. Par conséquent, le signal de test peut être programmé sans effort à partir de l'instrument numérique à haute-vitesse (HSD) d'un testeur à signaux-mixtes (ATE). De plus, un système précis et économique de génération de délai d'horloge est présenté comme une application du PLL construit. A l'aide de calibration et compensation appropriées, une résolution de délai de l'ordre de 15 ps est réalisée pour un intervalle de 8.4 ns. Cette technique est démontrée expérimentalement comme étant une solution viable pour l'alignement d'horloge et pour mesurer le vacillement d'horloge à un rythme de sous-échantillonnage de 50 GHz.
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Lemonnier--Le, Penhuizic Claire. "Effets d'oligosaccharides sur l'embryogenèse de microspores de brocoli : : mode d'action et transduction du signal." Rennes 1, 2001. http://www.theses.fr/2001REN10085.
Full textAbstract:
L'induction embryogène dans des cultures de microspores isolées est un processus dépendant d'un stress, qui peut être déclenché par un choc thermique, une privation de saccharose ou de nitrogène ou par l'utilisation d'inhibiteurs de la polymérisation des microtubules. Connus pour mimer des stress biotiques, les oligosaccharides ont été testés en tant que source de composés inducteurs de l'embryogenèse de microspores de Brassica napus var. Italica. Parmi les huit séries d'oligosaccharides étudiés et leurs polymères respectifs (à savoir des pectines, des alginates, des fucanes, des laminarines, des agars et des ?-, ?-, ?-carraghénanes) seuls les oligo-carraghénanes présentaient des effets significatifs sur l'induction des microspores. Ajoutés en combinaison avec un choc thermique, ils augmentaient très fortement les rendements finaux en embryons dérivés de microspores. Ainsi, un doublement du rendement était observé dans le cas du traitement le plus efficace, c'est-à-dire en présence d'oligo-?-carraghénanes. Le mode d'action des oligo-carraghénanes a été étudié en suivant le devenir d'oligosaccharides fluorescents. Les oligo-carraghénanes peuvent entrer dans les cellules ; toutefois, l'utilisation d'oligo-carraghénanes biotinylés immobilisés sur des billes de streptavidine a révélé que les molécules exerçaient probablement leurs effets au niveau extracellulaire. Les réponses ont été comparées avec celles obtenues lors de traitements avec des peptides contenant la séquence RGD (site de reconnaissance universel des molécules d'adhésion des cellules animales) sur des cultures de microspores. Les traitements à l'aide de peptides RGD présentaient des résultats similaires sur l'induction de l'androgenèse et semblaient entrer en compétition avec les sites de liaisons des oligo-carraghénanes. Des études pharmacologiques ont permis de montrer que la signalisation des oligo-carraghénanes et des peptides RGD présentent des voies de transduction communes, impliquant des protéines kinases et des MAP kinases, éléments distincts de la voie de transduction du choc thermique. Ces données ont permis de proposer un modèle hypothétique de l'induction de l'embryogenèse par modification de la polarité des microspores. Le développement propre des grains de pollen nécessite une adhésion polarisée pour établir de possibles connections au niveau cortical. . .
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Benyahya, Kaoutar. "Mode group division multiplexing for short reach optical communications." Thesis, Rennes 1, 2019. http://www.theses.fr/2019REN1S117.
Full textAbstract:
La demande croissante du trafic de données sera alimentée par des technologies révolutionnaires telles que la réalité virtuelle (VR), la réalité augmentée (AR) et l’Internet des objets (IoT). Par conséquent, les réseaux optiques devraient répondre aux besoins de ces services en termes de débit, faible temps de réponse et grande fiabilité. En effet, les hauts débits représentent un besoin critique pour les systèmes de communication à fibre optique déployés dans les réseaux locaux ainsi que dans les centres de données. Pour ces deux applications, les systèmes basés sur la modulation d'intensité et la détection directe de cette dernière sont très attractifs en raison de leur faible coût et de leur compatibilité avec les applications à courte distance. Dans le cadre de cette thèse, nous répondons à la nécessité d’augmenter les débits pour les systèmes de communication optiques à courte distance basés sur le multiplexage de groupe de modes et la détection directe. Tout d'abord, nous visons à augmenter la capacité des fibres multimodes standard déjà déployées dans les réseaux locaux et à l’intérieur des centres de données où la distance est inférieure à 5 km. Deuxièmement, nous étendons notre solution aux applications avec des distances de déploiement plus longues telles que les connexions entre les centres de données. Dans les deux cas, les architectures des liens optiques, y compris les émetteurs, les récepteurs et les fibres optiques, sont analysées. De plus, les formats de modulation adaptés aux systèmes basés sur la détection directe tels que le format de modulation mono-porteuse 4-PAM et celui multi-porteuse DMT sont comparés dans le contexte de la transmission basée sur le multiplexage spatial. Nous avons démontré les avantages du multiplexage de groupes de modes combiné à la détection directe pour augmenter le débit transmit sur une seule fibre. Premièrement, 5 Tb / s ont été démontré sur 2,2 km de fibre multimode conventionnelle (OM2). Deuxièmement, un record de transmission de 14,5 Tb / s sur fibre OM2 est démontré au moment correspondant à sa réalisation. Enfin, 200 Gb / s sur 20 km de fibre faiblement multimode (FMF) a été démontré, ce qui étend les avantages du multiplexage par groupes de modes aux applications à longue distance par rapport aux réseaux LAN où la distance maximale est limitée à 5 kmThe ever-growing demand of data traffic will be fuelled by revolutionary technologies such as virtual reality (VR), augmented reality (AR) and Internet of things (IoT). Therefore, optical networks should support the requirements of these services in terms of high capacity, low latency and high reliability. In fact, large scale capacity is a critical need for fiber optic communication systems deployed in local area networks as well as in datacenters. For both applications, systems relying on intensity modulation and direct detection (IMDD) are highly demanded due to their low cost and compatibility with short range applications. In this thesis, we address the need of increasing the data rates for short reach optical communication systems based on mode group division multiplexing and direct detection schemes. Firstly, we focus on increasing the capacity of already deployed standard multimode fibers in local area networks and intra-datacenters communication where the distance is shorter than 5 km. Secondly, we extend our solution to longer reach applications such as inter-datacenter interconnects. In both cases, optical link architectures, including transmitters, receivers and the optical fibers are analysed. Moreover, modulation formats adapted to IMDD systems such as single carrier 4-PAM and multicarrier DMT are compared in the context of space division multiplexing transmission. In this work we demonstrated the achievable benefit of mode group multiplexing combined with IMDD schemes. First, 5 Tb/s has been achieved over 2.2 km of conventional multimode fiber (OM2). Secondly, transmission record at the corresponding time of its realization of 14.5 Tb/s over OM2 fiber is demonstrated. Finally, 200 Gb/s over 20 km of FMF has been achieved which extend the benefit of mode group multiplexing to longer reach applications compared to LAN and intra-datacenter where the maximum distance is limited to 5 km
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Bennett, Michael J. "Signal processing techniques for ultrasonic tissue Doppler and real-time B-mode imaging in cardiology." Thesis, University of Edinburgh, 2005. http://hdl.handle.net/1842/10779.
Full textAbstract:
Coronary heart disease is the most common cause of death in the UK affecting more than one in five men and one in six women. The cause is generally a constriction of the coronary arteries which supply the heart muscle, or myocardium with blood. In around 95% of cases, the constriction is caused by the process of arteriosclerosis which results in the development of a plaque on the vessel wall. Even though these plaques tend to develop quite slowly, they are sometimes liable to sudden rupture, which causes clotting of the blood in the vessel and hence a sudden reduction in the supply of blood to the myocardium. This thesis is concerned with the signal processing techniques which are used in the form of Doppler Tissue Imaging (DTI) and real-time B-Mode imaging to study the motion of cardiac structures. Although these techniques are well suited to this task, improvements in B-mode contrast resolution and DTI velocity resolution are required if image quality and quantitative measurements are to reach a more acceptable level. Results are presented which demonstrate that the accuracy of the velocity estimations made using DTI can be improved with the use of model based signal processing techniques. The use of the fractional Fourier transform is explored in the context of coded excitation, which is a technique to allow improvements in imaging depth and axial resolution and results are shown which show that this technique is able to offer improvements similar to matched filtering. The combined techniques of empirical mode decomposition and the Hilbert spectrum are used to demonstrate a new interpretation of the physical process underlying non-linear acoustic wave propagation and the existing technique of tissue harmonic imaging.
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Quinlan, Franklyn. "LOW NOISE, HIGH REPETITION RATE SEMICONDUCTOR-BASED MODE-LOCKED LASERS FOR SIGNAL PROCESSING AND COHERENT COMMUNICATIONS." Doctoral diss., University of Central Florida, 2008. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3393.
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This dissertation details work on high repetition rate semiconductor mode-locked lasers. The qualities of stable pulse trains and stable optical frequency content are the focus of the work performed. First, applications of such lasers are reviewed with particular attention to applications only realizable with laser performance such as presented in this dissertation. Sources of timing jitter are also reviewed, as are techniques by which the timing jitter of a 10 GHz optical pulse train may be measured. Experimental results begin with an exploration of the consequences on the timing and amplitude jitter of the phase noise of an RF source used for mode-locking. These results lead to an ultralow timing jitter source, with 30 fs of timing jitter (1 Hz to 5 GHz, extrapolated). The focus of the work then shifts to generating a stabilized optical frequency comb. The first technique to generating the frequency comb is through optical injection. It is shown that not only can injection locking stabilize a mode-locked laser to the injection seed, but linewidth narrowing, timing jitter reduction and suppression of superfluous optical supermodes of a harmonically mode-locked laser also result. A scheme by which optical injection locking can be maintained long term is also proposed. Results on using an intracavity etalon for supermode suppression and optical frequency stabilization then follow. An etalon-based actively mode-locked laser is shown to have a timing jitter of only 20 fs (1Hz-5 GHz, extrapolated), optical linewidths below 10 kHz and optical frequency instabilities less than 400 kHz. By adding dispersion compensating fiber, the optical spectrum was broadened to 2 THz and 800 fs duration pulses were obtained. By using the etalon-based actively mode-locked laser as a basis, a completely self-contained frequency stabilized coupled optoelectronic oscillator was built and characterized. By simultaneously stabilizing the optical frequencies and the pulse repetition rate to the etalon, a 10 GHz comb source centered at 1550 nm was realized. This system maintains the high quality performance of the actively mode-locked laser while significantly reducing the size weight and power consumption of the system. This system also has the potential for outperforming the actively mode-locked laser by increasing the finesse and stability of the intracavity etalon. The final chapter of this dissertation outlines the future work on the etalon-based coupled optoelectronic oscillator, including the incorporation of a higher finesse, more stable etalon and active phase noise suppression of the RF signal. Two appendices give details on phase noise measurements that incorporate carrier suppression and the noise model for the coupled optoelectronic oscillator.Ph.D.
Optics and Photonics
Optics and Photonics
Optics PhD
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Schlottmann, Craig Richard. "A coordinated approach to reconfigurable analog signal processing." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/49021.
Full textAbstract:
The purpose of this research is to create a solid framework for embedded system design with field-programmable analog arrays (FPAAs). To achieve this goal, we've created a unified approach to the three phases of FPAA system design: (1) the hardware architecture; (2) the circuit design and modeling; and (3) the high-level software tools. First, we describe innovations to the reconfigurable analog hardware that enable advanced signal processing and integration into embedded systems. We introduce the multiple-input translinear element (MITE) FPAA and the dynamically-reconfigurable RASP 2.9v FPAA, which was designed explicitly for interfacing with external digital systems. This compatibility creates a streamlined workflow for dropping the FPAA hardware into mixed-signal embedded systems. The second phase, algorithm analysis and modeling, is important to create a useful and reliable library of components for the system designer. We discuss the concept and procedure of analog abstraction that empowers non-circuit design engineers to take full advantage of analog techniques. We use the analog vector-matrix multiplier as an example for a detailed discussion on computational analog analysis and system mapping to the FPAA. Lastly, we describe high-level software tools, which are an absolute necessity for the design of large systems due to the size and complexity of modern FPAAs. We describe the Sim2Spice tool, which allows system designers to develop signal processing systems in the Simulink environment. The tool then compiles the system to the FPAA hardware. By coordinating the development of these three phases, we've created a solid unified framework that empowers engineers to utilize FPAAs.
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Curtis, Eddie J. "Comprehensive on-street bicycle facilities: an approach for incorporating traffic signal operational strategies for bicycles." Thesis, Georgia Institute of Technology, 2015. http://hdl.handle.net/1853/53478.
Full textAbstract:
Less than 1% of work and school trips are completed by bicycle in the United States. Comprehensive bicycle facilities improve bicycle ridership by including a diverse set of strategies that accommodate the bicycle mode and seek to minimize the Level of Traffic Stress experienced by riders. Traffic Signal Operational Strategies for Bicycles (TSOSB) are an integral component of comprehensive bicycle facilities. This research presents a methodology to identify critical zones for implementation of TSOSB. After identifying critical zones a process for assessment of gaps in bicycle safety and comfort and convenience for signalized intersections within the critical zones is conducted. The outcome of the methodology is a prioritized list of signalized intersection that could benefit from the application of Traffic Signal Operational Strategies for Bicycles
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Ozharar, Sarper. "Stable optical frequency comb generation and applications in arbitrary waveform generation, signal processing and optical data mining." Orlando, Fla. : University of Central Florida, 2008. http://purl.fcla.edu/fcla/etd/CFE0002388.
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POMPEI, DOMINIQUE. "Caracterisation et selection des modes de propagation dans les lignes microondes : generalisation du formalisme quasi-tem, utilisation des techniques de traitement du signal dans la methode tlm." Nice, 1987. http://www.theses.fr/1987NICE4123.
Full textAbstract:
On developpe en 1ere partie un formalisme matriciel pour n lignes microbandes couplees dans le cas du mode quasi tem afin de pouvoir caracteriser leurs proprietes. En seconde partie on developpe des techniques de simulation et de filtrage en frequence pour selectionner les multiples modes generes. Autre que le quasi tem, on retient la technique de simulation tlm (transmission line matrix) apres avoir reduit le temps de calcul et l'occupation memoire. Pour le filtrage de mode, c'est au niveau du traitement du signal que l'apport est fait. Toutes ces techniques permettent d'etudier des structures multilignes et d'avoir acces aux caracteristiques de rayonnement des antennes imprimees
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Guo, Jing. "MULTI-MODE SELF-REFERENCING SURFACE PLASMON RESONANCE SENSORS." UKnowledge, 2013. http://uknowledge.uky.edu/ece_etds/13.
Full textAbstract:
Surface-plasmon-resonance (SPR) sensors are widely used in biological, chemical, medical, and environmental sensing. This dissertation describes the design and development of dual-mode, self-referencing SPR sensors supporting two surface-plasmon modes (long- and short-range) which can differentiate surface binding interactions from bulk index changes at a single sensing location. Dual-mode SPR sensors have been optimized for surface limit of detection (LOD). In a wavelength interrogated optical setup, both surface plasmons are simultaneously excited at the same location and incident angle but at different wavelengths. To improve the sensor performance, a new approach to dual-mode SPR sensing is presented that offers improved differentiation between surface and bulk effects. By using an angular interrogation, both surface plasmons are simultaneously excited at the same location and wavelength but at different angles. Angular interrogation offers at least a factor of 3.6 improvement in surface and bulk cross-sensitivity compared to wavelength-interrogated dual-mode SPR sensors.
Multi-mode SPR sensors supporting at least three surface-plasmon modes can differentiate a target surface effect from interfering surface effects and bulk index changes. This dissertation describes a tri-mode SPR sensor which supports three surface plasmon resonance modes at one single sensing position, where each mode is excited at a different wavelength. The tri-mode SPR sensor can successfully differentiate specific binding from the non-specific binding and bulk index changes.
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Kotecha, Ramchandra M. "Analysis and Comparison of Popular Models for Current-Mode Control of Switch Mode Power Supplies." Wright State University / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=wright1300211710.
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Peric, Vedran. "Non-intrusive Methods for Mode Estimation in Power Systems using Synchrophasors." Doctoral thesis, KTH, Elkraftteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-182134.
Full textAbstract:
Real-time monitoring of electromechanical oscillations is of great significance for power system operators; to this aim, software solutions (algorithms) that use synchrophasor measurements have been developed for this purpose. This thesis investigates different approaches for improving mode estimation process by offering new methods and deepening the understanding of different stages in the mode estimation process. One of the problems tackled in this thesis is the selection of synchrophasor signals used as the input for mode estimation. The proposed selection is performed using a quantitative criterion that is based on the variance of the critical mode estimate. The proposed criterion and associated selection method, offer a systematic and quantitative approach for PMU signal selection. The thesis also analyzes methods for model order selection used in mode estimation. Further, negative effects of forced oscillations and non-white noise load random changes on mode estimation results have been addressed by exploiting the intrinsic power system property that the characteristics of electromechanical modes are predominately determined by the power generation and transmission network. An improved accuracy of the mode estimation process can be obtained by intentionally injecting a probing disturbance. The thesis presents an optimization method that finds the optimal spectrum of the probing signals. In addition, the probing signal with the optimal spectrum is generated considering arbitrary time domain signal constraints that can be imposed by various probing signal generating devices. Finally, the thesis provides a comprehensive description of a practical implementation of a real-time mode estimation tool. This includes description of the hardware, software architecture, graphical user interface, as well as details of the most important components such as the Statnett’s SDK that allows easy access to synchrophasor data streams.The Doctoral Degrees issued upon completion of the programme are issued by Comillas Pontifical University, Delft University of Technology and KTH Royal Institute of Technology. The invested degrees are official in Spain, the Netherlands and Sweden, respectively.
QC 20160218
FP7 iTesla
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Du, Tzung-Tze, and 杜宗澤. "Signal Recognition by Using Empirical Mode Decomposition." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/39258799449139483328.
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Chen, Jyun Min, and 陳峻敏. "A Mixed-mode Biomedical Signal Interface Circuit." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/01660351017917260683.
Full textAbstract:
碩士輔仁大學
電機工程學系
101
In this thesis, a mix-mode biomedical signal interface circuit is proposed. This circuit removes the noise of transistors by chopper modulation, and the topology of the feedback loop eliminates the common-mode noise of the input signal. In order to reduce the variability of analog circuits, the input signal is digitized by the analog-to-digital converter (ADC) after amplification. The digitized signal is filtered through the digital filter in the digital domain. The input common mode noise is obtained from the digital low-pass filter and is fed back to the input by a digital-to-analog converter (DAC) for cancellation. Sharing the identical capacitor array in ADC and DAC, and implementing the low-pass filter in the digital domain avoid the large capacitor area requirement of the analog low-pass filter. This approach effectively reduce the circuit area. This circuit is designed with a CMOS 0.18m technology at a supply voltage of 1.8V. The chip area is 1.224mm X 1.348mm. The amplifier provides 100, 200, 400, and 800 four selections of magnification. The input range of 10-bit differential data converter is -1V~+1V and the sample frequency is 6.67kS/s.
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Yang, Chung-Huang, and 楊忠煌. "ISFET Performance Enhancement by Mixed-Mode Signal Processing." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/k3c6wr.
Full textAbstract:
博士中原大學
電子工程研究所
93
Abstract Silicon-based semiconductor micro sensors are now able to react to the ion concentration (activity). The ISFET has features of rapid reaction time, high sensitivity, batch processing, small size and single chip integration. Furthermore, it can be implemented by CMOS technology. These advantages make it the first choice for VLSI electrochemistry bio-inspired applications. ISFET has been characterized and measured, indicating drawbacks related to: thermal dependency, long-term drift and hysteresis. To enhance the accuracy in biomedical related research, it is necessary to find a compensation method to cancel or reduce these effects. In this thesis, a single chip implementation of an ISFET-based pH-meter system and a discrete temperature compensation chip have been successfully designed, fabricated and tested. The two-point calibration circuitry based on the response of standard pH4 and pH7 buffer solution has been implemented by using Algorithmic State Machine (ASM) hardware algorithms. For homeland environmental applications, the system provide rapid, easy to use, and cost-effective on-site testing on the quality of water, such as drinking water, ground water and river water. The processor has a potential usage in battery-operated and portable devices in environmental monitoring applications compared to commercial hand-held pH meter. In order to capture the response of the ISFET sensors, it is necessary for the ISFET to be accompanied by an analog readout interface. This study devises a new integrated ISFET electronic interface circuit embedded with noise rejection capability. In addition, an approach to enhance accuracy of the output signal obtained from ISFET interface electronics due to the body effect is proposed. The scheme allows reduction of influence of body effect. Using only one ISFET with a differential output configuration, we obtained temperature dependency and long-term drift as well as common noise compensation. Simulation and experimental results show a great effect on monolithic ISFET integration in CMOS technology.
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Alico, Jurgen. "Multiphase Optimal Response Mixed-signal Current Program Mode Controller." Thesis, 2009. http://hdl.handle.net/1807/18135.
Full textAbstract:
The primary focus of this thesis is to present a simple and practical implementation of an optimal-time response controller for multiphase interleaved dc-dc SMPS. This novel solution enables equal current sharing between phases not only in steady-state, but also during load transients, as well as bump-less transition between those two states. A digital voltage loop and multiple analog peak current programmed mode current loops are combined to implement a capacitor charge balance control algorithm with fairly simple hardware. This algorithm provides recovery from a disturbance in a single on-off switching action, which is performed in virtually the fastest possible time.
The hybrid interface between the loops is provided through a structure combining a sample-and-hold circuit and a relatively slow successive-approximation DAC that provides control signals for all the loops in the system. Furthermore, for operation under light load conditions, the controller automatically switches into simply implemented pulse-frequency mode of operation.
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Gao, Jiexin. "Towards a Unified Signal Representation via Empirical Mode Decomposition." Thesis, 2012. http://hdl.handle.net/1807/33208.
Full textAbstract:
Empirical mode decomposition was proposed recently as a time frequency analysis tool for nonlinear and nonstationary signals. Despite from its many advantages, problems such as “uniqueness” problem have been discovered which limit the application.
Although this problem has been addressed to some extent by various extensions of the original algorithm, the solution is far from satisfactory in some scenarios. In this work we propose two variants of the original algorithm, with emphasis on providing unified representations. R-EMD makes use of a set of reference signals to guide the decomposition therefore guarantees unified representation for multiple 1D signals. 2D- BEMD takes advantage of a projection procedure and is capable of providing unified representation between a pair of 2D signals. Application of the proposed algorithms on different problems in biometric and image processing demonstrates promising results and indicates the effectiveness of the proposed framework.
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Li, Ji-shian, and 李季憲. "Development of Digital Signal Processor Based Switched Mode Rectifiers." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/hjmbus.
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碩士國立臺灣科技大學
電機工程系
95
ABSTRACT This thesis presents the design and implementation of a digital signal processor based switched mode rectifiers for telecommunication power systems. A two-leg parallel-connected circuit with single-phase power factor correction is proposed for ac-dc power conversion. Equal and time-sharing current control is achieved through interleaved pulse-width-modulation to reduce input current ripple. In addition, current-predicted control is used to raise the power factor to unity. On the other hand, dc-dc power conversion is designed with full-bridge power circuit. The zero-voltage switching is accomplished by phase-shifted control to reduce switching loss. The current doubler rectifiers installed at output side can reduce conducting loss of output filtering inductors. Finally, the introduction of load power compensating control in power factor correction circuit will improve system performance and reduce the input current harmonics. In this thesis, switch equivalent circuit is first derived and then simulated by Matlab/Simulink to verify the proposed control strategy. The 32-bit digital signal processor, TMS320F2812, is used to implement the control functions of the system. The control functions of voltage and current closed-loop controls are realized by software to reduce circuit components and improve reliability. In addition, the digital signal processor communicates with personal computer by controller area network interface for real-time monitoring. An experimental system of 48V, 500W output power for 110V, 60Hz input is built with the dc-link voltage of 380V. The efficiency is 89% in full-load operations, and the power factor is 0.993. The total harmonic distortion of input current is 4%, which complies with IEEE Std 519-1992.
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Cheng, Shao-Chun, and 鄭少鈞. "A Novel Mixed-Mode Signal Processor Design by Current-Mode Circuits for Biomedical Sensing System." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/79148296750872794243.
Full textAbstract:
碩士中原大學
電子工程研究所
97
The purpose of this research is to design a biomedical sensing system which can sense different kinds of physiological parameters (e.g. glucose, uric acid, etc.). The described system utilized amperometric sensor to measure the physiological parameters which is designed using current-mode circuits. The biomedical sensing system consists of three sub-circuits: 1) potentiostat, 2) current comparator, and 3) current-mode pipeline ADC (analog to digital converter). The sub-circuits were implemented using current-mode circuits, making this research different from others. Some researches used different methods in which the input current is still to be converted to output voltage then use the voltage-mode ADC. This work, however, uses input current signals directly eliminating the need for converting current signals to voltage. The highlight of this research is the implementation of the sensing system which made it more suitable for low voltage system. Since the output signal is current, the range of output is not limited by low voltage power supply. Another advantage of this research is its wide dynamic range of sensing current. This is used to simultaneously sense both glucose level (large sensing current) and uric acid level (small sensing current). The first stage of this system is a novel potentiostat readout circuit which can sense current from 250 pA to 80 μA. The second stage is a novel current comparator which is the core of the third stage of this system. The advantage of the novel current comparator is its high accuracy, in which the differential current of the current comparator can be as small as 0.6 nA and still maintaining a valid output on the current comparator. Increasing the accuracy of current comparator will also increase the resolution of current mode ADC. Therefore, the system can sense more kind of physiological parameters. The whole system is implemented using TSMC 0.35 μm Mixed-Signal 2P4M Polycide 3.3V/5V process of National Chip Implementation Center (CIC), Taiwan. The chip was tested by measuring the glucose level of the glucose solution. The signal linearity were measured, analyzed and recorded using LabVIEW.
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郭榮銘. "Balanced Bandpass Filter Designs of Possessing Common Mode Signal Suppression." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/21460279845801258052.
Full textAbstract:
碩士建國科技大學
電子工程系暨研究所
99
This thesis aims to research the design of common mode rejection of balanced bandpass filter, and implement in micro-wavelet board. In the first part of this thesis, I study the basic principles of balanced bandpass filter, the two- two-level Step impedance Resonators (SIR), the external quality factor of a single load resonators, the coupling coefficient of a coupled resonator, Split-Ring Resonators (SRR), Defected Ground Structure (DGS) and so on, as the theoretical basis of this thesis. In the second part, first of all, a pair of similar SRRs and a pair of DGSs embedded in the ground plane are used to design a band-pass filter which could satisfy both differential mode response and common mode rejection response. The broadband response mainly utilize the strong coupling mechanism so that the already split modal is divided again to form four poles to prop up the key to form broadband. In addition, a bandstop effect is generated by a pair of DGS to form a zero point mechanism and designed in the common-mode resonance point so as to reduce the signal pass to achieve the suppression effect. In the third part, this thesis uses the configuration of T-type and λ/2 SIR resonator to design the balanced dual band pass filter structure with common mode rejection. The main concept is to design a good differential mode signal using λ/2 SIRs of 2.45 GHz and 5.25 GHz, and the T-resonator in differential mode has the same signals through; In common mode, there is a zero suppression in the common-mode resonance point generated by λ / 2 SIRs. In this thesis, an open stub is used to form a zero point mechanism to strengthen the common mode signal suppression. The designed circuit in this study is verified by real circuit. The result shows that either broadband or balanced dual band pass filter has a very good response to the differential mode and the common mode. Expected the completions of broadband and balanced dual band pass filters in this thesis can be applied to the OFDM and WLAN in the actual communication system. The proposed design method can be used as a useful reference for R & D personnel.
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Huang, Chien-ming, and 黃建銘. "DSP Implementation of Empirical Mode Decomposition for ECG Signal Processing." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/98430266128831295357.
Full textAbstract:
碩士國立中央大學
電機工程研究所
96
The empirical mode decomposition (EMD), Recently, has been used extensively to the analysis of the signal. EMD, which use yardstick change of time within signals to resolve signals into the combination of several intrinsic mode functions (IMFs). IMFs contain different characteristics of signals and can express the physical characteristics in signals. The Electrocardiogram (ECG) is one of the import methods for diagnosis of heart diseases. But the ECG recordings are often corrupted by baseline wander and power line interference. Baseline wander is mainly caused by subjects breathing and movement. The power line interference also corrupt the ECG signals, which come from power lines to the measurement equipments. These interferences may cause the ECG distortion and lead to wrong diagnosis. This study proposed DSP implementation of the EMD algorithm and develop a complete system for signal processing without computer.
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Huang, Jie-Cyun, and 黃捷群. "A Pipelining Empirical Mode Decomposition for Emotionalized Speech Signal Processing." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/37261152719232626254.
Full textAbstract:
碩士清雲科技大學
電子工程系所
97
In this thesis, the pipelining technique is integrated into the empirical mode decomposition of the nonlinear signal processing. This newly pipelining empirical mode decomposition also is applied to construct the front processing unit of an emotionalized spontaneous speaker and speech recognition system in this thesis. This novel approach owns the ability to reduce the computing time, so it can empower our emotionalized spontaneous speaker and speech recognition system to satisfy the real-time requirement. There are proved that the speech recognition rate’ difference between the pipelined and non-pipelined voice signals are less than 3%, even though the pipelined voice signals have some distortions. The experiments in the final part of this thesis present the detail comparisons between the pipelined and non-pipelined signals and speech recognition rates. The architecture of the speech recognition system in an emotionalized spontaneous speech includes four major parts: speech signal processing, pipelining empirical mode decomposition, feature extraction, and dual-model identification systems. That feature is to use the pipelining empirical mode decomposition technique to online extract the speaker voice characteristics and identification first, and then to find out the personal and characteristic vocabulary voice model of the person, according to the model to identify the pronunciation voice commands is the last step. This design makes the voice commands identification more accurate, and the stored vocabulary voice model can also owns the personal characteristic of some specified speaker simultaneously.
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Yeh, Jia-Rong, and 葉家榮. "APPLICATIONS OF EMPIRICAL MODE DECOMPOSITION (EMD) IN PHYSIOLOGICAL SIGNAL ANALYSIS." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/82879254109505190946.
Full textAbstract:
博士元智大學
機械工程學系
97
The functions of the human body are frequently associated with physiological signals, which convey hidden information, determined by the various complicated underlying mechanisms. Moreover, physiological signal processing and analysis are interdisciplinary topics. A physiological system is non-linear and non-stationary, therefore, most of traditional algorithms based on linear assumption cannot satisfy the requirements for physiological signal analysis. Recently, empirical mode decomposition (EMD) was proposed as a signal processing and analysis algorithm for nonlinear and non-stationary systems. EMD also performs as an adaptive analysis algorithm, which doesn’t need a priori. In 2006, we used EMD and found that helps in research on physiological signal analysis. Therefore, we decide to focus our research on the processing algorithms of EMD and its correlated applications. In the processing algorithm, we proposed a noise enhanced algorithm of complementary ensemble empirical mode decomposition (CEEMD) to solve the mode-mixing problem of the original EMD and to improve the efficiency of EEMD. According to signals with or without dominant components, physiological signals are assorted into two different categories. A broad-band signal is defined as a signal without dominant components and a narrow-band signal is a signal with dominant components. Moreover, EMD acts as a natural filter bank for narrow-band signals and as a dyadic filter bank for broad-band signals. Therefore, we developed different applications of EMD according to the essential characteristics of the signals. These applications include the complexity quantification, verification of high-frequency fluctuation in signals, and the intrinsic component extraction. In this thesis, we present three different applications of EMD on physiological signal analysis to demonstrate the functions of EMD. In the first application of complexity quantification, EMD acts as a dyadic filter bank to decompose a human heartbeat interval into several IMFs adaptive to the intrinsic timescales and power-law distributions of data. The power-law distribution presents a long-term correlation, just as Hurst exponent and DFA scaling exponents do. Moreover, the distribution of intrinsic timescales of signals presents an extra property in a signal. Thus, the two-parameter scheme of complexity quantification was developed using the intrinsic timescale and power-law distributions. In addition, we developed two different approaches, the EMD-based DFA and the intrinsic mode analysis (IMA), to investigate human heartbeat interval. We found that the distribution of intrinsic timescales performs as a good indicator for patients with of without heart disease (i.e., CHF or AF) and the power-law distribution performs as an indicator for aging. In addition, EMD associates with Monte Carlo verification to act as a filter, which can be used to filter high-frequency noise from a signal. In the second application of EMD associating with linguistic analysis, we demonstrate the use of EMD as a filter. In such an application, the blocking index is designed using the distant measurement of similarity. Moreover, the blocking index is succeeded in verifying the fluctuation pattern of blood pressure (BP) during artery clamping or relaxing. In the third and last application, EEMD acts to decompose the intrinsic components from narrow-band signals, such as ECG and BP. We demonstrate two approaches of intrinsic component extraction. Here, an intrinsic component is defined as an IMF, which presents the response of a particular physiological mechanism. These two approaches of intrinsic component extraction are the EEMD-based reflected wave quantification and multi-modal analysis. EEMD works to extract the reflected waves from BP in the EEMD-based reflected wave quantification and the cardiac oscillations from ECG and BP in the multi-modal analysis. In this application, these EEMD-based analysis methods are succeeded in figuring out the correlations among systolic arterial pressure (SAP), arterial stiffness, and dynamic property of the circulation system. Without doubt, EMD is a powerful signal processing and analysis algorithm for signals measured from nonlinear and non-stationary systems. Although, the development of processing algorithm and the application of EMD is still at an early stage, we derived useful information from the physiological signals by these analysis algorithms based on EMD or EEMD. We believe that we can create more applications of EMD for physiological signal analysis in the future.
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YEH, CHIH-CHEN, and 葉治成. "Elimination of Common-Mode Noise Using Time-Offset Differential Signal." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/51067389982755048691.
Full textAbstract:
碩士國立臺灣科技大學
電子工程系
100
In this thesis, the timing-offset differential signal is proposed to eliminate the differential-to-common mode conversion induced by the unequal paths of the bended differential transmission line, which includes the bended differential transmission line using the right-angle bend, differential serpentine delay line and differential serpentine delay line with strongly-coupled turns. The improvement is demonstrated as follows. First of all, in order to eliminate the TDT common mode noise of bended differential transmission line using the right-angle bend, the timing-offset differential signal is applied on the bended differential transmission line. The measured TDT common-mode noise is about 0.019V, which is much smaller than 0.065V of the bended differential transmission line without the timing-offset signal. Besides, the measured TDR differential-mode noise is about 0.023V, which is also smaller than 0.033V of the bended differential transmission line without the timing-offset signal. Furthermore, in order to investigate the frequency-domain S-parameters, we introduce the idea of equivalent S-parameters for the timing-offset bended differential transmission line. According to the simulation results, the timing-offset bended differential transmission using the right-angle bend can substantially reduce the mode conversion, which has 7 dB improvement from DC to 6 GHz. Besides, the timing-offset bended differential transmission line using the right-angle bend does not increase the differential-mode or common-mode reflection at the sending end. Also, it can increase the differential-mode to differential-mode transmission at the receiving end. In addition, the phase of the differential-mode to differential-mode transmission has a linear response. Finally, in order to investigate the insights of the reduction of the mode conversion, we extract the equivalent circuit parameters of the timing-offset bended differential transmission line using the right-angle bend. According to the equivalent circuit parameters, since the self-inductance (L13=2.0822 nH) of the inner path is quiet close to the self-inductance (L24=2.0688 nH) of the outer path and the self-capacitance (C11= C33=0.16837 pF) of the inner path is also close to self-capacitance (C22= C44=0.2535 pF) of the outer path, the differential signal on the inner and outer paths will approximately reach the receiving end at the same time, causing a great reduction in the common noise. Secondly, we investigate the differential serpentine delay line and differential serpentine delay line with strongly-coupled turn. Owing to the even number of the coupled delay line, the lengths of the inner and outer paths become unequal, inducing the common mode noise at the receiving end. In order to reduce the common mode noise, the timing-offset differential signal is applied on the differential serpentine delay line. The mode conversion of the timing-offset differential serpentine delay line is below –13dB from DC to 15GHz. As compared with mode conversion of the differential serpentine delay line, the mode conversion is reduced. Besides, the amplitude of the TDT common-mode noise at the receiving end is reduced from 0.0289 V to 0.0117 V whereas the amplitude of the TDR differential-mode noise at the sending end is not increased. Furthermore, the timing-offset differential signal is applied to the serpentine delay line with strongly-coupled turn so as to further reduce the common mode noise. The mode conversion of the timing-offset differential serpentine delay line with strongly-coupled turns is below –18dB from DC to 15GHz. As compare with the mode conversion of the differential serpentine delay line with strongly-coupled turns, the mode conversion is decreased. Besides, the amplitude of the TDT common-mode noise at the receiving end is reduced from 0.0154 V to 0.0065 V whereas the amplitude of the TDR differential-mode noise at the sending end is not increased. In order to verify the simulation results of the timing-offset serpentine delay line and timing-offset serpentine delay line with strongly-coupled turns, 5.72 times scaled down serpentine delay lines are fabricated and measured. The measurement results of the scaled down circuits, which are in good agreement with the simulation results, verifies our designs.
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Wu, Chi-hsun, and 吳奇勳. "Extraction of EEG/MEG Signal Features Using Empirical Mode Decomposition." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/34944762489271172220.
Full textAbstract:
博士國立中央大學
電機工程學系
101
Electroencephalography (EEG)/Magnetoencephlography(MEG) has been applied for investigation of neuroscience and diagnosis of many neurological disorders. The noninvasive EEG recordings are overlapping potentials from spontaneous brain rhythm, physiological artifact and external interference. Accordingly, extraction task-related signal features is crucial in the field of EEG/MEG signal processing. The aim of this study is to develop an EMD-based approach to extract single-trial EEG signal. The EMD method decomposed an EEG/MEG epoch into various scale of sub-band component called intrinsic mode function (IMF) and customized the recognition of task-related component to suppress the task-unrelated component. This dissertation evaluates the performance of EMD in EEG or MEG signal into the applications of steady-state visual evoked potential based brain computer interface (SSVEP-based BCI), sensorimotor mu rhythm extraction and olfactory event-related potential extraction. To evaluate the performance of SSVEP feature extraction, this study presents an empirical mode decomposition (EMD) and refined generalized zero crossing (rGZC) approach to achieve frequency recognition in SSVEP-based BCI. The EMD-rGZC improves the information transfer rate (ITR). Event-related desynchronization (ERD) and synchronization (ERS) analysis methods have been widely used in studying movement-related sensorimotor functions in human brain. Movement-related ERD is functionally related to motor planning and initialization, while movement-related ERS is related to motor inhibition and motor cortex resetting. This study developed a single-trial brain rhythm analysis method based on EMD method to discover the mechanisms of ERD and ERS in normal subjects and Parkinson’s patients as well, which could be used as a clinical index for diagnosing Parkinson’s patients. In the study of olfactory event-related potential (OERP) feature extraction, we developed an EMD-based approach to extract OERP from multi-channel EEG recordings. The EMD approach decomposes a signal into IMFs by iteratively conducting the sifting process. Dual criteria on frequency and spatial template were adopted to facilitate the selection of OERP-related IMFs and to reconstruct single-trial OERP for inter-trial investigation.
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Chi-Hsien and 賴其賢. "56Gb/s High-speed Signal Transmission along Single-mode Fiber." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/umqdr9.
Full textAbstract:
碩士國立臺灣科技大學
電子工程系
105
This work investigates the transmission of 56Gb/s PAM-4 and NRZ signals through a single-mode fiber to satisfy the requirement of IEEE 400GBASE-LR8 standard. We also compare the performance and discuss the challenges of high-speed data transmission using the direct modulation lasers and external-modulation lasers. High-speed information transmission stimulates the fast increasing bandwidth demands that becomes very challenging for modern communication networks. The researchers are working hard to develop high-speed data transmission technologies that can meet the bandwidth growth demand while lowering the cost and energy consumption of the optical transceivers. For data centers, optical communication is the most effective solution. After 100Gb/s transceivers were commercialized, 400Gb/s optical transceivers become one of the hottest research topic and many advancements are published in the journals and conferences. However, there are many challenges yet to be overcome. In this thesis we successfully demonstrated the transmission of 56Gb/s PAM-4 signals using an electro-absorption modulation laser over up to 10km of single-mode fiber and obtained a bit-error-rate (BER) of about 〖10〗^(-5), which can be improved to 〖10〗^(-12) by using and equalizer on the receiver end. The transmission of 56Gb/s NRZ signal along 10-km single-mode fiber can have a BER of roughly 〖10〗^(-6). These results lay a foundation of realizing 400Gb/s optical transceivers using 8-channel of 56-Gb/s light sources.
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Chen, Szu-Yu, and 陳思予. "Reformed Intrinsic Mode Decomposition and its Application for Signal Processing." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/2z5f5e.
Full textAbstract:
碩士國立臺灣師範大學
機電科技研究所
97
Signal processing is very important for science and engineering researches. Real world signals are often noisy, non-stationary, and obtained from nonlinear systems. However, the majority of signal processing algorithms proposed in the literature such as Fourier transform are better suited for analyzing the linear stationary signals with weak noise. Empirical Mode Decomposition (EMD) provides a powerful tool for adaptive multi-scale analysis of nonlinear and non-stationary signals. In this thesis, the proposed improvement way of three main topics on the algorithm, stopping criterion, envelope and boundary effect, were summarized and compared. In addition, we make a brief introduction involving orthogonality condition of basis functions, the limitation of decomposition capacity and reconstruction issue of basis functions. It inspired us to propose the Reformed Intrinsic Mode Decomposition (RIMD) by the study of piecewise linear signals in the literature. The best feature of piecewise linear processing is to obtain the faster decomposition efficiency. In this study, we utilize this notion to get middle points and then establish the mean envelope, and propose following methods for the application of real signals: connecting middle points by cubic spline, connecting middle points by the propotion of the original signal, and finding the mean envelope. RIMD is not only reducing the computational cost but also decreasing the selection of extrema for the boundary effect. It will make signals smoother and more symmetric in the sifting process. At last, the results of decomposition using RIMD for the simulated and testing signals were analysized and discussed.
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Lin, Shao Wei, and 林劭瑋. "The Large Signal Model of Enhancement–Mode pHEMT and Microwave Tripler Circuit DesignThe Large Signal Model of Enhancement–Mode pHEMT and Microwave Tripler Circuit Design." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/95886604736216491955.
Full textAbstract:
碩士長庚大學
電子工程研究所
95
InGaP/InGaAs pHEMT device is one of the most important device of Ⅲ-Ⅴsemiconductors in military and commercial communication applications at microwave and millimeter-wave frequencies. It is extremely important to model the characteristics of the transistors before you use the transistors to design a MMIC circuit. To know the dc, RF or noise characteristics of the transistors accurately are the essential issues of designing the MMIC circuits, such as low noise amplifiers. This thesis contains both the small-signal and large-signal modeling methods of the InGaP/InGaAs pHEMT. The determined small- signal equivalent circuit by using the small-signal modeling method described in this thesis fits the S-parameters very well up to 20 GHz. The nonlinearity of dc characteristics and intrinsic elements of the InGaP/InGaAs pHEMT are investigated. several empirical nonlinear equations, which are used in the modified Angelov model, are adapted to model these nonlinear effects and give a good agreement both in dc and RF characteristics of the devices. A Ka band tripler have been realized in a 0.15μm GaAs pHEMT technology. The circuits are based on different 180 power divider structures. The circuits achieve minimum conversion loss of -16 dB.
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Yang, Chao-Kun, and 楊朝坤. "Monitoring an Active Mode-Locked Fiber Laser Using the Internal Second Harmonic Signal of Its Mode Locker." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/98539548410895133019.
Full textAbstract:
碩士逢甲大學
光電物理研究所
92
In this thesis we used a distribution feedback type laser diode as an active mode locker, and built up an active mode-locked fiber ring laser using circulator, polarization controller, erbium–doped fiber amplifier and fiber coupler. With the help of a dichroic beamsplitter, we can measure the internal second harmonic signal of the mode locker. In this experiment, pulse train at a repetition rate of 993.247 MHz (153th harmonic of fundamental frequency of ring cavity) was obtained. The pulse width was 201 ps. The side-mode suppression ratio was 52.7 dB. When the fiber laser was actively mode-locked, we observed the internal second harmonic to be 14 pW. We observed the internal second harmonic to be 5pW as the laser was not actively mode-locked. So we can monitor an active mode-locked fiber laser using the internal second harmonic signal of its mode locker. In the future, this mode-locked laser can be used as a 1.5µm optical frequency comb.
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Zhong, Guo-Jun, and 鍾國俊. "Wideband Common-mode Suppression Filter Design for Multi Differential Signal Pairs." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/8cdu46.
Full textAbstract:
碩士國立臺北科技大學
電腦與通訊研究所
102
In this thesis, we proposed a wideband common-mode suppression filter for multi differential signal pairs. The method of the proposed design is utilized by using defected ground structure (DGS) of quarter-wavelength resonators with the mutual coupling effect between the quarter-wavelength resonators to achieve the wideband common-mode suppression. The proposed structure is fabricated on printed circuit board (PCB) with low coast and simple manufacture. In multi differential signal pairs, we still have an advantage of a wideband common-mode suppression. For observing one pair differential signal lines in the frequency domain analysis, the differential-mode insertion loss are all above -3 dB from DC to 10 GHz. For the common-mode insertion loss, a wide common-mode suppression bandwidth is 4.2 GHz by using -15 dB definition. The equivalent circuit model of the proposed DGS resonators has also been constructed to predict the phenomenon of the common mode suppression. Then, the result shows a good agreement between simulation and measurement. The results indicate that the proposed common-mode filter has broadband operation on common-mode suppression and multi differential signal pairs. In addition, it can maintaining the good signal integrity of differential signal pairs. Finally, by measuring eye diagrams and frequency domain results validate Wideband Common-mode Suppression Filter Design for Multi Differential Signal Pairs.
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Tse-AnChen and 陳則安. "A Dual-Mode AC Signal Processing IC for Bio-Sample Detection." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/40611188309951510635.
Full textAbstract:
碩士國立成功大學
電機工程學系碩博士班
98
With the improvement of sanitation, the invention of vaccines, the innovation of medical technology, and the progress in health care systems, the incidence of disease is significantly decreased, the cure rate is also increased and the average life of human being has been prolonged significantly. Therefore, the biomedical detection can early detect the disease and even prevent disease gets more and more attention. In recent years, integrating biomedical detection technology into chips is one of the main trends in IC design field. By integrating the circuits, people can perform their basic bio-detections at home, with no need to go to hospital. The presented chip uses the electrochemical impedance spectroscopy (EIS) method. Compared with other bio-sample detection methods, this detection method is much faster, and both the input signals and measured signals are all electro signals, so it can be directly and effectively integrated the circuit into the system chip. This chip contains the entire front-end input signal processing circuit and sensing circuits of the bio-sample detection system. The input signal processing circuits can provide two sets of identical constant voltage or constant current AC signals. Its frequency range is from 10 Hz to 10 kHz, its output voltage range is 1.5V~3.5V, and the maximum magnitude of its output current is 1mA. Besides, the sensing circuits detect the magnitude and phase of the measured signals, and convert them into DC outputs. The die area of this chip is 1.7x2.0mm^2 , and the package is 40 S/B. The chip was implemented by Taiwan Semiconductor Manufacturing Company (TSMC) 0.35μm 2P4M 5V mixed-signal polycide process, patronized by National Chip Implementation Center (CIC).