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Basti, Ahmed. "Développement de méthodes de synthèse pour la conception de filtres hyperfréquences compacts et optimisés en pertes." Thesis, Limoges, 2014. http://www.theses.fr/2014LIMO0023/document.
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Pour les systèmes de communication par satellite, des filtres avec de très bonnes performances électriques sont indispensables afin de rejeter les signaux indésirables dans de nombreuses parties de la chaîne de communication. Les technologies fort-Q peuvent répondre à cette exigence mais elles conduisent souvent à des dispositifs encombrants. D'autre part, les technologies compactes faible-Q souffrent généralement d'une dégradation des performances électriques en termes de pertes d'insertion, de sélectivité et de platitude. Pour répondre à une demande croissante concernant la réduction de la taille, il est essentiel de développer des filtres hyperfréquences compacts avec des performances électriques améliorées.Pour le filtre de réception, le défi est de concevoir un filtre passe-bande compact avec une réponse plate dans la bande passante et une forte réjection hors bande. Les pertes d'insertion ne sont pas cruciales et peuvent être compensées par un amplificateur en laissant ainsi un espace pour la conception de filtre à pertes. Un tel filtre accepte des pertes supplémentaires, qui peuvent être distribués dans le réseau afin de fournir une transmission plate dans la bande passante et une forte sélectivité hors bande.Dans le cadre de cette thèse, des nouvelles méthodes de synthèse de dispositifs de filtrage ont été étudiées et développées dans le but d’améliorer les performances tout en conservant un encombrement réduit. Ces méthodes ont été validées pour la conception de filtres de récepteur dans la charge utile de satellites de télécommunication dans le cadre d’une collaboration entre le laboratoire Xlim, le Centre National d’Etudes Spatiales et Thales Alenia SpaceFor satellite communication systems, high performance filters are needed in order to reject unwanted signals in many parts of the communication chain. High quality factor (Q) technologies can meet this requirement, but they often lead to bulky devices. On the other hand, compact technologies are generally low Q and suffer from a degradation of electrical performances in terms of insertion loss, selectivity and flatness. To meet a growing demand concerning size reduction, it is essential to develop compact microwave filters with improved electrical performances.For a receive filter, the challenge is to design a compact bandpass filter with a flat response in the passband and a sharp transition in the passband edges. The insertion loss is not crucial and it can be compensated by the amplifier, leaving a room to the design of a lossy filter. Such a filter accepts additional losses, which can be distributed in the network in order to provide a flat transmission in the passband and a sharp selectivity.In this thesis, new synthesis methods for filtering devices have been studied and developed to improve performances while maintaining a small footprint. These methods have been validated for the design of filters for a receiver in payload satellites as part of collaboration between the Xlim laboratory, the France National Space Centre and Thales Alenia Space
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Shadrin, Aleksandr. "Analogové pole pro realizaci programovatelného filtru." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-221026.
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The state-variable analog filter topologies are described. Using the transfer function theory and operational configurations suitable for integration and derivation, a new universal filter topology are proposed. The circuit has been implemented in CMOS technology by using six operational amplifiers, eight analog switches and five programming resistor array. Tunable corner frequencies, quality factors and gain are realized. Using the serial peripheral interface or digital memory can be realized this real-time digitally programmable first- and second-order analog filter with the tunable parameters.
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Haidar, Ahmad. "Synthèse de filtres hyperfréquences prenant en compte le comportement dispersif des couplages." Thesis, Limoges, 2018. http://www.theses.fr/2018LIMO0105/document.
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Ces travaux de thèse concernent la mise au point d’une méthodologie de conception de filtres passe-bandes à couplages dispersifs permettant d’optimiser la sélectivité de ces filtres en générant et en contrôlant la position de zéros de transmission supplémentaires. Un état de l’art sur les différentes approches proposées dans la littérature pour la synthèse de filtres hyperfréquences à couplage dispersif est d’abord proposé. Cette analyse est illustrée par plusieurs exemples concrets, et une structure en particulier, comportant un couplage par plot capacitif, constitue le point de départ des travaux. De nouveaux éléments de couplage dispersifs ont été ensuite proposés, capables de générer aussi bien des couplages positifs que négatifs, permettant ainsi de positionner les zéros de transmission dans la bande stoppée supérieure ou inférieure. Ces éléments ont alors été intégrés dans des structures de filtrage plus complexes pour réaliser par exemple des structures en ligne possédant plusieurs zéros de transmission hors bande ou des filtres multibandes à la sélectivité renforcée. Plusieurs des dispositifs conçus ont été fabriqués et mesurés. Les résultats expérimentaux sont en bon accord avec les simulations validant ainsi l’approche proposéeThis thesis report deals with the development of a methodology for the design of bandpass filters including dispersive coupling to optimize the selectivity of these filters by generating and controlling the position of additional transmission zeros. A state of the art on the different approaches proposed in the literature for the synthesis of microwave filters with dispersive coupling is first proposed. This analysis is illustrated by several concrete examples, and a structure in particular, comprising a coupling capacitive post, is the starting point of the work. New dispersive coupling elements were then proposed, capable of generating both positive and negative couplings, thus enabling the transmission zeros to be positioned in the upper or lower stopped band. These elements have then been integrated in more complex filtering structures to achieve, for example, on-line structures having several out-of-band transmission zeros or multiband filters with enhanced selectivity. Many of the devices designed have been manufactured and measured. The experimental results are in good agreement with the simulations validating the proposed approach
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Zlámal, Jiří. "Návrh elektronicky laditelných kmitočtových filtrů v technologii CMOS." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-221016.
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This master thesis deals with the problematics of CT filters and focuses on Gm – C filter. Three linearisation techniques are listed and compared in terms of linear input range, distortion and retuning. In the practical part – second - order low – pass filter is designed and its tuning capabilities are examined.
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Demirsoy, Süleyman Sırrı. "Complexity reduction in digital filters and filter banks." Thesis, University of Westminster, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.433680.
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Vrba, Adam. "Analýza a realizace kmitočtového filtru přeladitelného změnou parametru aktivního prvku." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218675.
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This work analyzes tuning capabilities of different fully integrated active filter topologies. Work only deals with continuous time active filters. Topologies described in this work differ in type of active element and in method of frequency tuning. Techniques of tunning are proved on second order low pass filter. Filter topologies are compared from tunning capabilities and from point of total harmonic distortion. The main building block of all filters is integrator.
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Eshghi, Mohammad. "Highly parallel transversal adaptive filter." Ohio : Ohio University, 1988. http://www.ohiolink.edu/etd/view.cgi?ohiou1182785469.
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Rosenbaum, Linnea. "On low-complexity frequency selective digital filters and filter banks." Doctoral thesis, Linköpings universitet, Elektroniksystem, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-8930.
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En filterbank består av flera filter som arbetar tillsammans för att dela upp en signal i olika frekvensband. De kan också användas för att slå ihop signaler separerade i frekvensplanet till en enda. Sedan tidigt 70-tal har man lärt sig att designa förlustfria filterbankar som alltså inte introducerar några som helst fel i systemet. Sådana filterbankar kallas PR-filterbankar, där PR står för 'perfekt rekonstruktion'. Exempel på applikationer där filterbankar används är bildkodning, audiokodning, kommunikationssystem och omvandling av analoga signaler till digitala (A/D-omvandling). Under de senaste åren har det framkommit att genom att lätta på kraven gällande perfekt rekonstruktion, går det att markant minska den erforderliga aritmetiska komplexiteten. Eftersom de flesta system i sig inte är förlustfria, kan man utan att egentligen påverka den totala prestandan tillåta små fel i filterbanken, så l¨ange dessa fel är försumbara i jämförelse med andra felkällor som t.ex. kvantisering och avrundning. Avhandlingen behandlar digitala filter och likformiga icke-PR-filterbankar. Merparten av filterbankarna är realiserade med någon slags moduleringsteknik (cosinus-, sinus- eller komplexmodulering). Den röda tråden genom avhandlingen är kombinationen av tämligen smala övergångsband och samtidigt låg aritmetisk komplexitet. Ett sätt att uppnå denna kombination är att använda sig av en teknik som heter frekvenssvarsmaskning och förkortas FRM. Denna metod har på ett framgångsrikt sätt använts i avhandlingen. En potentiell nackdel med FRMmetoden är att den medför en längre fördröjning genom systemet. Därför föreslås också ett sätt att syntetisera FRM-filter med låg fördröjning. Här optimeras filtren både med avseende på komplexitet och fördröjning samtidigt. En annan metod som utnyttjats för att kombinera relativt smala övergångsband med låg aritmetisk komplexitet är att använda IIR filter istället för FIR filter. Ett flertal exempel på filter och filterbankar, optimerade och syntetiserade i Matlab, illustrerar fördelarna med de föreslagna filter- och filterbanks-klasserna.Filter banks are systems of several filters with a common input or a common output. They are used whenever a signal needs to be split into different frequency bands. Since the early seventies, the theory of digital filter banks has developed to a mature state. Today there exist numerous ways to design filter banks for different applications, such as image and audio coding, transmultiplexing in communication systems, echo cancellation, and analog-to-digital (A/D) conversion systems. However, earlier work has to a large extent been on the transfer function level, whereas in this thesis work, efficient realizations, important in e.g. low-power applications, are in focus. Further, most of the previous work have been focused on the perfect reconstruction (PR) case, which is, for many applications an unnecessarily severe restriction. It has been show that by relaxing the requirements on perfect reconstruction, and allowing the filter banks to have some errors, the arithmetic complexity can be reduced significantly. This thesis treats digital filters and uniform non-PR filter banks. A major part of the filter banks are realized using different modulation schemes (complex, cosine, or sine modulation). The governing idea through the thesis is the combination of frequency selectivity and low arithmetic complexity. One example on how to achieve frequency selective digital filters and filter banks with low arithmetic complexity is to use the frequency-response masking (FRM) approach. This approach together with the idea of using IIR filters instead of FIR filters is successfully used in the thesis. The price to pay for the reduced arithmetic complexity using FRM filters is unfortunately a longer overall delay. Therefore, some work has ben done in the field of low-delay FRM FIR filters as well. These filters are optimized on both low delay and low arithmetic complexity simultaneously. A number of design examples are included in order to demonstrate the benefits of the new classes of filters and filter banks.
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Rosenbaum, Linnéa. "On low-complexity frequency selective digital filters and filter banks /." Linköping : Department of Eelectrical Engineering, Linköpings universitet, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-8930.
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Anderson, Martin S. "Design of two-dimensional PCAS digital filters and filter banks." Thesis, University of Warwick, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307968.
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Cadena, Pico Jorge Eduardo. "Perfect Reconstruction Filter Bank Structure Based On Interpolated FIR Filters." Thesis, Virginia Tech, 2016. http://hdl.handle.net/10919/71756.
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State of the art filter bank structures achieve practically perfect reconstruction with very high computational efficiency. However, the increase in computational requirements due to the need to process increasingly wider band signals is paramount. New filter bank structures that provide extra information about a signal while achieving the same level of required efficiency, and perfect reconstruction properties, need to be developed. In this work a new filter bank structure, the interpolated FIR (IFIR) filter bank is developed. Such a structure combines the concepts of filter banks, and interpolated FIR filters. The filter design procedures for the IFIR filter bank are developed and explained.
The resulting structure was compared with the non-maximally-decimated filter bank (NMDFB), achieving the same performance in terms of the number of multiplications required per sample and the overall distortion introduced by the system, when operating with Nyquist prototype filters.
In addition, the IFIR filter is tested in both simulated and real communication environments. Performance, in terms of bit-error-rate, was found to not be degraded significantly when using the IFIR filter bank system for transmission and reception of QPSK symbols.Master of Science
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Chen, Tsuhan Vaidyanathan P. P. Vaidyanathan P. P. "Multidimensional multirate filters and filter banks : theory, design, and implementation /." Diss., Pasadena, Calif. : California Institute of Technology, 1993. http://resolver.caltech.edu/CaltechETD:etd-08232007-095226.
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Hrdina, Robin. "Návrh laditelného kmitočtového filtru 2. řádu v technologii CMOS." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2016. http://www.nusl.cz/ntk/nusl-242168.
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This master’s thesis deals with the design of tuneable frequency second order filter in CMOS technology. The thesis describes the design of a transconductor and its utilization for tunable gm-C filter. The design and all simulations were made in Cadence Spectre and Virtuoso software. Limitedly Orcad Pspice and SNAP were also used.
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Kennedy, Paul B. (Paul Brodie). "Filter designer : an intuitive digital filter design environment." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23849.
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The ability to accurately manipulate the spectral content of audio is indispensable for the artistic presentation of sound. While there are many devices currently available that are capable of performing this function, most tend to be either highly complex electrical engineering tools, or music-oriented products that are limited in functionality. Filter Designer was created to fill this gap by providing an environment with which musically-trained users can design and implement digital filters, while having access to control parameters and analysis data previously exclusive to the engineering field. This work explores the factors that motivated the creation of Filter Designer, and examines the process of its development, from basic user interface design to the calculation and implementation of digital filters for use with audio signals.
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Chow, Albert C. (Albert Chin-Hoa) 1977. "Active filter techniques for reducing EMI filter capacitance." Thesis, Massachusetts Institute of Technology, 2002. http://hdl.handle.net/1721.1/87314.
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Morzfeld, Matthias, Daniel Hodyss, and Chris Snyder. "What the collapse of the ensemble Kalman filter tells us about particle filters." TAYLOR & FRANCIS LTD, 2017. http://hdl.handle.net/10150/623125.
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The ensemble Kalman filter (EnKF) is a reliable data assimilation tool for high-dimensional meteorological problems. On the other hand, the EnKF can be interpreted as a particle filter, and particle filters (PF) collapse in high-dimensional problems. We explain that these seemingly contradictory statements offer insights about how PF function in certain high-dimensional problems, and in particular support recent efforts in meteorology to 'localize' particle filters, i.e. to restrict the influence of an observation to its neighbourhood.
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Deville, Yannick. "Filtres actifs RC hyperfréquences intégrés sur arséniure de gallium." Grenoble 1, 1989. http://www.theses.fr/1989GRE10015.
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Les filtres etudies sont en grande partie des filtres d'ordre 2: filtres passe-bande a forte selectivite, filtre coupe-bande, filtres passe-tout. Ces filtres passe-tout ont ete utilises pour realiser des dephaseurs 90**(o) large bande
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Kuřina, Tomáš. "Deinterlace Filter." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2009. http://www.nusl.cz/ntk/nusl-236788.
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This document elaborates on the subject of video interlacing and its removal. It describes the interlacing of video, its history and the reasons that led to its use. The document also explains why it is necessary to remove interlacing and the basic methods that are used for it. It describes the proposed deinterlacing algorithm and its implementation, including description of inpainting and block matching. Included are also test results of both quality and speed of my deinterlacing algorithm. The final chapter describes the implementation as a console application and a DLL library.
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Law, Ying Man. "Iterative algorithms for the constrained design of filters and filter banks /." View abstract or full-text, 2004. http://library.ust.hk/cgi/db/thesis.pl?ELEC%202004%20LAW.
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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2004.Includes bibliographical references (leaves 108-111). Also available in electronic version. Access restricted to campus users.
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Bui, Van Bien. "La stabilité du filtre non-linéaire en temps continu." Thesis, Nice, 2016. http://www.theses.fr/2016NICE4002/document.
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Le problème de filtrage consiste à estimer l'état d'un système dynamique, appelé signal qui est souvent un processus markovien, à partir d'observation bruitées des états passés du système. Dans ce mémoire, nous considérons un modèle de filtrage en temps continu pour le processus de diffusion. Le but est d'étudier la stabilité du filtre optimal par rapport à sa condition initiale au-delà de l'hypothèse de mélange (fort) pour le noyau de transition en ignorant l'ergodicité du signalThe filtering problem consists of estimating the state of a dynamic, called signal which is often a Markov process, from the noisy observation of the past states. In this thesis, we consider a filtering model in continuous time for the diffusion process. The aim is to study the stability of the optimal filter with respect to its initial condition beyond the mixing (or quasi – mixing) hypothesis for the transition kernel
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Kumar, Bhunesh. "Design of Harmonic Filters for Renewable Energy Applications." Thesis, Högskolan på Gotland, Institutionen för kultur, energi och miljö, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:hgo:diva-1862.
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Harmonics are created by non-linear devices connected to the power system. Power system harmonics are multiples of the fundamental power system frequency and these harmonic frequencies can create distorted voltages and currents. Distortion of voltages and currents can affect the power system adversely causing power quality problems. Therefore, estimation of harmonics is of high importance for efficiency of the power system network. The problem of harmonic loss evaluation is of growing importance for renewable power system industry by impacting the operating costs and the useful life of the system components. Non-linear devices such as power electronics converters can inject harmonics alternating currents (AC) in the electrical power system. The number of sensitive loads that require ideal sinusoidal supply voltage for their proper operation has been increasing. To maintain the quality limits proposed by standards to protect the sensitive loads, it is necessary to include some form of filtering device to the power system. Harmonics also increases overall reactive power demanded by equivalent load. Filters have been devised to achieve an optimal control strategy for harmonic alleviation problems. To achieve an acceptable distortion, increase the power quality and to reduce the harmonics hence several three phase filter banks are used and connected in parallel. In this thesis, high order harmonics cases have been suppressed by employing variants of Butterworth, Chebyshev and Cauer filters. MATLAB/SIMULINK wind farm model was used to generate and analyze the different harmonics magnitude and frequency. High voltage direct current (HVDC) lines for an electrical grid that is more than50km far away wind farm generation plant was investigated for harmonics. These HVDC lines are also used in offshore wind farm plant. Investigated three-phase harmonics filters are shunt elements that are used in power systems for decreasing voltage distortion and for correcting the power factor. Renewable energy sources are not the stable source of energy generation like wind, solar and tidal e.t.c. Though they are secondary sources of generation and hard to connect with electrical grid. In near future the technique is to use the wave digital filter (WDF) or circulator-tree wave digital filter (CTWDF) for the renewable energy application can be employed to mitigate the harmonics. These WDF and CTWDF can b eused in HVDC lines and smart grid applications. A preliminary analysis is conducted for such a study.
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Bragina, Tatiana. "Návrh laditelného kmitočtového filtru 2. řádu se spínanými kapacitory." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2014. http://www.nusl.cz/ntk/nusl-221041.
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Thesis describes analog filters topologies with capability of tuning of the main parameters and the MOSFET-C and switched-capacitor filters are described. With focus to linearity and maximal tuning range optimal topology have been chosen. In work the issue of analog switch design is described and is solved. Design of switched-capacitor low-pass Sallen-key filter in Cadence software was made and simulation results are presented.
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Chen, Min. "Implementation and optimization of a modulated filter bank based on allpass filters." Thesis, University of Ottawa (Canada), 2001. http://hdl.handle.net/10393/9192.
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A filter bank based on an allpass IIR filter with brick-wall response was designed by A. J. Van Leest in [17]; however, the delay in the filter bank is too long to be used in real time applications. In order to reduce the delay, the orders of coefficients, transition bandwidth and filter bank structures must be optimized. The order of coefficients can be reduced by increasing the stopband attenuation. In order to further reduce the delay, the sharpness of the filter bank has to be reduced. This thesis also discussed the number of band and filter bank structure against to filter bank delay. The filter bank can be used in non-real time application such as CD compression with high order coefficient. The minimum transition bandwidth can be reached at 0.03257pi/number of band. This thesis expands upon DCT modulations of IIR based modulated filter banks and investigate the Hartley transformation in filter bank modulation as a new modulation technique. These modulation techniques generate the real output signal with real input signals. The quantization errors from quantizing the coefficient are studied. It is concluded that at least 16 bits are required in order for a filter bank to give a good performance as designed without quantization.
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Baicher, Gurvinder Singh. "Towards optimisation of digital filters and multirate filter banks through genetic algorithms." Thesis, University of South Wales, 2003. https://pure.southwales.ac.uk/en/studentthesis/towards-optimisation-of-digital-filters-and-multirate-filter-banks-through-genetic-algorithms(1ed2778b-e27b-4434-bc50-915f697a0d6b).html.
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This thesis is concerned with the issues of design and optimisation of digital filters and multirate filter banks. The main focus and contribution of this thesis is to apply the genetic algorithm (GA) technique and to draw some comparison with the standard gradient and non-gradient based optimisation methods. The finite word length (FWL) constraint affects the accuracy of a real-time digital filter requency response. For the case of digital filters, this study is concerned with the optimisation of FWL coefficients using genetic algorithms. Some comparative study with the simple hill climber algorithms is also included. The outcome of this part of the study demonstrates a substantial improvement of the new results when compared with the simply rounded FWL coefficient frequency response. The FWL coefficient optimisation process developed in the earlier Chapters is extended to the field of multirate filter banks. All multirate filter banks suffer from the problems of amplitude, phase and aliasing errors and, therefore, constraints for perfect reconstruction (PR) of the input signal can be extensive. The problem, in general, is reduced to relaxing constraints at the expense of errors and finding methods for minimising the errors. Optimisation techniques are thus commonly used for the design and implementation of multirate filter banks. In this part of the study, GAs have been used in two distinct stages. Firstly, for the design optimisation so that the overall errors are minimised and secondly for FWL coefficient optimisation of digital filters that form the sub-band filters of the filter bank. This process leads to an optimal realisation of the filter bank that can be applied to specific applications such as telephony speech signal coding and compression. One example of the optimised QMF bank was tested on a real-time DSP target system and the results are reported. The multiple M-channel uniform and non-uniform filter banks have also been considered in this study for design optimisation. For a comparative study of the GA optimised results of the design stage of the filter bank, other standard methods such as the gradient based quasi-Newton and the non-gradient based downhill Simplex methods were also used. In general, the outcome of this part of study demonstrates that a hybrid approach of GA and standard method was the most efficient and effective process in generating the best results.
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Mlích, Jozef. "Sledování objektů ve videosekvencích." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2008. http://www.nusl.cz/ntk/nusl-235922.
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In this master thesis, image processing methods and methods for statistical modeling of motion are presented. First, description methods of image processing, such as background subtraction method used for object detection, are presented. Next, description of morphological operations, such as dilatation and erosion, is done. Finally, methods for statistical modeling, such as Kalman filter and particle filters, are shown.
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Cao, Hui. "Smoothed Particle Filter." INTELLIGENT MEDIA INTEGRATION NAGOYA UNIVERSITY / COE, 2005. http://hdl.handle.net/2237/10425.
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Leuschner, Jens. "Mail-Filter-Funktionen." [S.l.] : Techn. Univ. Chemnitz, Fakultät für Informatik, 2002. http://www.bsz-bw.de/cgi-bin/xvms.cgi?SWB10607538.
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Huang, Yuchen. "Adaptive Notch Filter." PDXScholar, 1994. https://pdxscholar.library.pdx.edu/open_access_etds/4802.
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The thesis presents a new adaptive notch filter (ANF) algorithm that is more accurate and efficient and has a faster convergent rate than previous ANF algorithms. In 1985, Nehorai designed an infinite impulse response (UR) ANF algorithm that has many advantages over previous ANF algorithms. It requires a minimal number of parameters with constrained poles and zeros. It has higher stability and sharper notches than any ANF algorithm until now. Because of the special filter structure and the recursive prediction error (RPE) method, however, the algorithm is very sensitive to the initial estimate of the filter coefficient and its covariance. Furthermore, convergence to the true filter coefficient is not guaranteed since the error-performance surface of the filter has its global minimum lying on a fairly flat region. We propose a new ANF algorithm that overcomes the convergence problem. By choosing a smaller notch bandwidth control parameter that makes the error-performance surface less flat, we can more easily detect a global minimum. We also propose a new convergence criterion to be used with the algorithm and a self-adjustment feature to reset the initial estimate of the filter coefficient and its covariance. This results in guaranteed convergence with more accurate results and more efficient computations than previous ANF algorithms.
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Metref, Sammy. "Assimilation de données pour les problèmes non-Gaussiens : méthodologie et applications à la biogéochimie marine." Thesis, Université Grenoble Alpes (ComUE), 2015. http://www.theses.fr/2015GREAU019/document.
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L'assimilation de données pour les géosciences est une discipline cherchant à améliorer notre connaissance d'un système physique en se basant sur l'information issue de modèles numériques simulant ce système et sur l'information issue des mesures observant ce système. Les méthodes d'assimilation de données traditionnellement utilisées (e.g. le 4DVar ou les filtres de Kalman d'ensemble) reposent sur des hypothèses de Gaussianité des probabilités en jeu et de linéarité des modèles. Avec la complexification des modèles et des réseaux d'observations, ces hypothèses sont de plus en plus injustifiées et donc pénalisantes. Cette complexification est particulièrement forte en océanographie couplée à la biogéochimie marine.Les objectifs de cette thèse sont de mieux comprendre l'apparition des non-Gaussianités dans un problème d'estimation, d'envisager une méthode d'assimilation de données adaptée aux problèmes fortement non-Gaussiens et, dans le cadre du couplage de la dynamique océanique et de la biogéochimie marine, d'explorer la pertinence de l'utilisation de méthodes non-Gaussiennes.Dans un premier temps, une étude méthodologique est conduite. Cette étude, appuyé par des illustrations avec le modèle de Lorenz à trois variables, permet de mettre en évidence les limitations des méthodes traditionnellement utilisées, face à des problèmes non-Gaussiens. Cette étude aboutit sur le développement d'un filtre d'assimilation de données d'ensemble entièrement non-Gaussien : le Multivariate Rank Histogram Filter (MRHF).Il est montré que le MRHF est performant dans des régimes fortement non-Gaussiens (notamment dans un régime bimodal) pour un nombre de membres relativement faible.Dans un second temps, une étude numérique est conduite. Cette étude est réalisée aux travers d'expériences jumelles basées sur un modèle vertical 1D, ModECOGeL, couplant la dynamique et la biogéochimie en mer Ligure. Nous simulons différents réseaux d'observations combinant des profils in situ et des données satellites. Plusieurs méthodes d'assimilation sont alors comparées à l'aide de diagnostics d'évaluation d'ensemble avancés.Nos expériences montrent l'impact du réseau d'observations et des variables de contrôle, sur le degré de non-Gaussianité d'un problème d'estimation. Le contrôle de la partie dynamique du modèle par des observations de la dynamique à différentes fréquences est un problème quasi-Gaussien, qu'un filtre aux moindres carrés, tel l'Ensemble Transform Kalman Filter, résout bien. En revanche pour ces mêmes observations, le contrôle de la biogéochimie s'avère être un problème non-Gaussien et nécessite l'utilisation d'un filtre non-Gaussien.Enfin, il est montré que l'assimilation de la couleur de l'eau, pour le contrôle mixte de la dynamique et de la biogéochimie, est améliorée par des méthodes adaptées aux non-Gaussianités, tel l'Ensemble Kalman Filter anamorphosé. De plus, l'augmentation de la fréquence d'observation de la couleur de l'eau rend incontournable l'utilisation de filtres fondamentalement non-Gaussiens comme le MRHFData assimilation for Geosciences is a discipline seeking to improve our knowledge of a physical system based on the information from numerical models simulating this system and the information from the measures observing this system. The data assimilation methods traditionally used (eg the 4DVAR or the ensemble Kalman filters) are based on assumptions of Gaussianity of the probabilities involved and linearity of the models. With the increasing complexity of models and observation networks, these assumptions are increasingly unjustified and therefore penalizing. This complexity is particularly strong in oceanography coupled with marine biogeochemistry.The objectives of this thesis are to understand the appearance of non Gaussianity in an estimation problem, to think out a data assimilation method adapted to highly non Gaussian problems and, in the coupling of ocean dynamics and marine biogeochemistry, to explore the relevance of the use of non Gaussian methods.At first, a methodological study is conducted. This study, supported by illustrations with the three variable Lorenz model, allows to highlight the limitations of traditional methods when facing non Gaussian problems. This study led to the development of a fully non Gaussian data assimilation filter : the Multivariate Rank Histogram Filter (MRHF).It is shown that the MRHF is efficient in highly non Gaussian regimes (including in a bimodal regime) for a relatively small number of members.Secondly, a numerical study is conducted. This study is conducted with twin experiments based on a 1D vertical model, ModECOGeL, coupling dynamics and biogeochemistry in the Ligurian Sea. We simulate different observation networks combining in situ profiles and satellite data. Several data assimilation methods are then compared using advanced ensemble evaluation diagnoses.Our experiments show the impact of observation networks and controled variables on the degree of non Gaussianity in an estimation problem. The control of the dynamic part of the model by observations of the dynamics at different frequencies is a quasi Gaussian problem, which a least squared filter such as the Ensemble Transform Kalman Filter solves well. In contrast, for the same observations, the control of biogeochemistry proves to be a non Gaussian problem and requires the use of a non Gaussian filter. Finally, it is shown that assimilation of ocean color data, for the joint control of the dynamic and the biogeochemistry, is improved by methods adapted for non Gaussianities such as the Anamorphosed Ensemble Kalman Filter. In addition, increasing the ocean color observation frequency makes unavoidable the use of fundamentally non Gaussian filters such as the MRHF
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Guerrero, Enriquez Rubén Dario. "Etude des filtres miniatures LTCC High K en bandes L&S." Thesis, Brest, 2016. http://www.theses.fr/2016BRES0036/document.
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Dans les systèmes actuels de communication, qu’ils soient terrestre ou spatial, qu’ils soient mobile ou fixe, il y a un réel intérêt à développer des front-ends radiofréquences et hyperfréquences miniatures et performants. Ceci s’applique en particulier aux dispositifs de filtrage où l’encombrement et les facteurs de qualité sont clairement antagonistes. Pour les bandes de fréquences basses aux alentours du GHz, les longueurs d’onde restent encore importantes, rendant difficiles les efforts de miniaturisation. D’autre part il faut aussi s’assurer que ces filtres viendront s’interconnecter aisément avec les autres composants du système, notamment les actifs.Pour toutes ces raisons, le développement de structures de filtres multicouches utilisant des substrats à haute permittivité (εr = 68) selon une approche LTCC apparait comme une alternative intéressante. Elle peut en effet conduire à une réduction significative de l'empreinte (footprint) sans pour autant trop nuire aux performances électriques.Dans le cadre de ce travail, deux structures de filtres multicouches ont été développées pour répondre à des spécifications proposées en bandes L et S, par un équipementier du spatial. Ces filtres ont pour caractéristiques principales un haut niveau de rejection et des faibles pertes dans la bande passante. Pour atteindre les spécifications, un filtre SIW empilé verticalement et un filtre à stubs en court-circuit en configuration triplaque ont été étudiés. Le filtre SIW se distingue par un facteur de qualité élevé, ce qui entraîne des faibles pertes d’insertion et une bonne platitude. La solution à stub permet quant à elle de réduire l’encombrement mais au prix d’un impact sur les performances électriques. Dans les deux cas on tire parti de la souplesse offerte par la technologie LTCC, puisqu’elle offre finalement un degré de liberté supplémentaire, par rapport à une approche planaire classique. Si dans le cas SIW, c’est surtout l’architecture topologique qui a été étudiée finement pour pouvoir agencer et coupler douze cavités, dans le cas du filtre à stub une synthèse mettant à profit tous les degrés de liberté offerts a été spécifiquement développée.Compte tenu de la complexité des filtres, notamment à cause de l’ordre élevé et de la mise en oeuvre de murs « électriques » à partir d’arrangements de via spécifiques, une attention particulière doit être apportée lors des phases de simulation et d’optimisation. De plus la très forte permittivité du substrat ne permet pas d’utiliser de ligne 50 Ohms. Enfin les transitions constituent un point dur de l’exercice surtout dans le cas SIW.Cette thèse co-financée par le CNES (Centre National d'Etudes Spatiales) et Thales Alenia Space, était accompagnée par un projet R&T financé par le CNES. Le fondeur allemand Via Electronic avait en charge la fabrication des filtresIn current communication systems, whether terrestrial or spatial, whether fixed or mobile, there is a real interest in developing high performance miniature RF front-ends. This is applied in particular to filter devices, in which the size and the quality factors are clearly in conflict. For low frequency bands around the GHz, the wavelengths remain significant, making it difficult the miniaturization efforts. On the other hand, we must also ensure that these filters will be easily interconnected with other other system components, including active devices.For all these reasons, the development of multilayer filter structures using high permittivity substrates (Er = 68) in an LTCC approach is consolidated as an interesting alternative. It may lead to a significant footprint reduction without decreasing the electrical performances.As part of this work, two multilayer filter structures have been developed to meet the given specifications in L and S bands, given by a space manufacturer. These filters have as main features a high rejection level and low losses in the passband. To meet the specifications, a vertically stacked SIW filter and a short-circuited stubs filter in a stripline configuration were studied. The SIW filter is characterized by a high quality factor, which results in low insertion loss and good flatness. The stubs filter allows in contrast to reduce the footprint but at the price of impacting the electrical performance. In both cases we take advantage of the flexibility offered by the LTCC technology as it finally provides an additional freedom degree compared to a conventional planar approach. For the SIW filter, the topological architecture was studied and designed in detail, to be able to arrange and synthetize couplings between twelve cavities. In a similar way, for the stub filter a synthesis that takes profit of all the offered freedom degrees was developed.Given the filters complexity, especially due to the high order and the implementation of “electrical walls" based on specific vias patterns, a close attention must be paid during the simulation and optimization phase. In addition, the high permittivity substrate does not allow to conceive 50-Ohms lines. Finally, access transitions constitute a challenging task, especially for the SIW case.This thesis was co-funded by CNES (Centre National d'Etudes Spatiales) and Thales Alenia Space, and was accompanied by an R&T project funded by CNES. The German foundry Via Electronic was responsible for the filters fabrication
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Terblanche, Phillip. "Electronically adjustable bandpass filter." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/17966.
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Thesis (MScEng)--Stellenbosch University, 2011.ENGLISH ABSTRACT: This thesis presents the study, analysis and design of electronically tunable filters, that can be tuned over a wide frequency range (20-500MHz), for use in a direct sampling receiver. The final design does not have to be a single filter, but may be comprised of a filter bank which enables switching between the filters. The band of interest is too low to use normal transmission lines and lumped elements have to be used. Different topologies that can implement Coupled Resonator filters with lumped elements are investigated. Devices that can be used for tuning are also investigated and varactor diodes are found to be the most suitable tuning devices currently available. Two filters, one at the high-end and one at the low-end of the band, were designed and built, both using varactor diodes. These filters perform well in terms of tuning range, but achieving low losses with current technologies in this band remains difficult.
AFRIKAANSE OPSOMMING: Hierdie tesis meld die studie, analise en ontwerp van elektronies verstelbare filters, wat verstelbaar is oor ’n wye band (20-500MHz), vir gebruik in ’n direk-monster-ontvanger. Die finale ontwerp hoef nie ’n enkele filter te wees nie, maar kan bestaan uit ’n filterbank wat skakeling tussen die filters toelaat. Die betrokke band is te laag vir die gebruik van normale transmissielyne en diskrete komponente moet gebruik word. Verskillende topologieë wat gekoppelde resoneerder filters implementeer met diskrete komponente is ondersoek. Verstelbare komponente word ook ondersoek en varaktor diodes blyk die mees geskikte verstelbare komponent wat huidig beskikbaar is in hierdie band. Twee filters, een aan die hoë kant en een aan die lae kant van die band, is ontwerp en gebou, beide met varaktor diodes. Hierdie filters het wye verstelbare bereik, maar dit is steeds moeilik om verliese te beperk met die huidige tegnologie.
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Sence, Johann. "Contribution au co-design et à la co-intégration de réseaux d’antennes actives multi-bandes pour systèmes de radionavigation par satellite." Thesis, Limoges, 2019. http://www.theses.fr/2019LIMO0087.
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Ce travail de thèse s’inscrit dans le contexte actuel d’une très forte augmentation de la densité d’intégration des systèmes électroniques pour les équipements de communications, de localisation ou de surveillance. Le déploiement de ces systèmes doit aussi répondre à une demande croissante de flexibilité en termes de fréquences, de puissance ou de couverture. La flexibilité en fréquence peut être simultanée avec des dispositifs multi-bandes ou sélective par reconfiguration de la bande de fréquence. La flexibilité en puissance permet de minimiser la consommation du système et la flexibilité de couverture d’orienter le faisceau vers la cible afin d’optimiser le bilan de liaison ou au contraire se protéger d’une source de bruit. L’augmentation de l’efficacité et de la compacité passe par le regroupement de fonctions élémentaires (LNA/filtre/antenne) qui permet de réduire les étages d’interconnexion et de prendre en compte les interactions entre les différents éléments. L’objectif premier de ce projet est donc de développer une méthodologie de conception conjointe de l’antenne et des circuits associés (filtres et LNA) pour atteindre des performances (rayonnement, efficacité, etc.) optimales avec un dispositif intégré et compactThis work takesplace in the context of developingelectronic systems for communications equipment, localization or monitoringequipment with a high integration density. The deployment of these systems must also meet a growing demand for flexibility in terms of frequencies, power or coverage. The frequency flexibility can be simultaneous with multiband devices or selective by reconfiguring the frequency band. The power flexibility enables to minimize consumption of the system and the coverage flexibility to direct the beam to the target to optimize the budget link or otherwise protect a source of noise. The increase in efficiency and compactness passes through the combination of elementary functions (LNA / filter / antenna) that reduces interconnect floors and considering the interactions between the different elements. The primary objective of this project is to develop a co-design methodology of the antenna with the associated circuits (filters and LNA) to achieve optimal performances (radiation,efficiency, ...) with an integrated and compact device
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Davati, Soheil. "VLSI implementation of recursive digital notch filter." Ohio : Ohio University, 1986. http://www.ohiolink.edu/etd/view.cgi?ohiou1183128831.
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Liu, Che. "Design a Bandpass Filter for GSM 900 : Parallel Coupled Line Filter Design." Thesis, Högskolan i Gävle, Avdelningen för elektronik, matematik och naturvetenskap, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-15502.
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González, Sánchez María Fernanda. "Separate treatment of wash water from sand filter using disc filter technology." Thesis, KTH, Mark- och vattenteknik (flyttat 20130630), 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-171843.
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The purpose of this study is to evaluate the convenience and effectiveness of using a disc filter to treat washing water from the sand filters at Sundet wastewater treatment plant. The disc filter is used aiming for the reduction of suspended solids and phosphorus. The study was divided in two main experimental stages. During the first stage laboratory jar-tests were performed in order to identify which flocculation aid was more suitable, this was further on used to improve the water treatment. Based on the laboratory trials results, two different polymers (1 and 2) were chosen to be tested at pilot scale. The second stage involved the pilot filter operation itself; this period was as well divided in two sub-stages where filter cloths with two different pore openings were tested. During the first sub-stage the pilot operated with an 18 μm pore opening filters cloth and both polymers. At the end of the first half polymer 1 showed to be more efficient and so it was further used throughout the second sub-stage in combination with a 10μm pore opening filter cloth. As from theoretical knowledge the phosphorus and suspended solid removal were expected to be between 75% and 90%, results which were achieved during both laboratory trials and pilot filter. The best results were observed with the 10μm pore opening filter cloth and polymer 1. Also, additional results from pilot trials performed at Sundet after the study period are presented.
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Schelbert, Peter Gottfried. "Signalangepasste Filter in Oberflächenwellentechnik /." [S.l.] : [s.n.], 1992. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=9799.
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Wörman, Johan, and Ted Davidsson. "Examensarbete Variable filter solution." Thesis, Halmstad University, School of Business and Engineering (SET), 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-4227.
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Nord, Magnus. "Cosine Modulated Filter Banks." Thesis, Linköping University, Department of Electrical Engineering, 2003. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-1641.
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The initial goal of this report was to implement and compare cosine modulated filter banks. Because of time limitations, focus shifted towards the implementation. Filter banks and multirate systems are important in a vast range of signal processing systems. When implementing a design, there are several considerations to be taken into account. Some examples are word length, number systems and type of components. The filter banks were implemented using a custom made software, especially designed to generate configurable gate level code. The generated code was then synthesized and the results were compared. Some of the results were a bit curious. For example, considerable effort was put into implementing graph multipliers, as these were expected to be smaller and faster than their CSDC (Canonic Signed Digit Code) counterparts. However, with one exception, they turned out to generate larger designs. Another conclusion drawn is that the choice of FPGA is important. There are several things left to investigate, though. For example, a more thorough comparison between CSDC and graph multipliers should be carried out, and other DCT (Discrete Cosine Transform) implementations should be investigated.
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Helsing, Håkon. "Dynamisk rekonfigurerbart digitalt filter." Thesis, Norwegian University of Science and Technology, Department of Electronics and Telecommunications, 2009. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-10552.
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Denne masteroppgaven er et arbeid mot et system med et dynamisk rekonfigurerbart digitalt FIR-filter på FPGA. Filteret benytter konstantmultiplikatorer optimalisert med CSD-kode for lite areal og kort rekongureringstid samtidig som høy fleksibilitet. Filterstruktur og partisjoneringsalternativer for oppdeling i dynamisk og statisk design er analysert, det er sett på betydningen ved bruk av bussmakroer, og det er sett på muligheten for bruk av multiplikatormoduler med dynamisk størrelse for eventuelt å gjenbruke ledig logikk. Tre filtervarianter er simulert og syntetisert mot Virtex-4 på et testkort av typen Suzaku-V. Et FIR-filter på transponert form med individuelle delvis rekonfigurerbare konstantmultiplikatormoduler gir et godt utgangspunkt for videre arbeid. Arbeidet er en videreføring av prosjektoppgaven der det ble laget et program som genererer FIR-filtre og CSD-enkodede konstantmultiplikatorer i VHDL. Prosjektoppgaven ble skrevet i desember 2008.
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Chen, Charng-Kann, and 陳常侃. "Optimal Design of Digital Filters and Digital Filter Banks." Thesis, 1994. http://ndltd.ncl.edu.tw/handle/60246289762306954645.
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博士國立臺灣大學
電機工程研究所
82
The work of this dissertation is to devise novel and efficient techniques for optimally designing one-dimensional (1-D) digital filters, two-dimensional (2-D) digital filters, 1-D multirate filter banks, and 2-D multirate filter banks in the appropriate optimal sense. As for the 1-D digital filters, the proposed techniques include the design algorithms for designing quasi-equiripple FIR and IIR digital filters, discrete coefficient FIR digital filters with arbitrary amplitude and phase response, digital all-pass filters, high order digital differentiators using $L_{1}$ error criteria, sharp FIR digital filters with prescribed group delay phase response, and cascade form FIR digital filters with powers-of-two coefficients in the complex domain, and Chebyshev design of IIR digital filters with arbitrary magnitude and phase responses. On the other hand, this dissertation also presents two approaches for equiripple design of 2-D linear-phase FIR digital filters. One approach is based on a novel minimax design method and the other approach is the McClellan transform based design techniques. With regard to the 1-D filter bank systems, a deep study of designing quadrature mirror filters (QMF) with linear phase in the frequency domain using different optimal criteria is given. The powers-of-two coefficient design of QMF bank is considered, too. Other than the uniform-division QMF banks, the design of two-channel nonuniform-division maximally decimated filter banks is thoroughly studied. Considering the design of 2-D multirate filter bank systems, a novel minimax design of 2-D nonseparable QMF banks with non-diagonal decimation/ expansion matrix is presented. It is shown that the quincunx QMF bank and the parallelogram QMF bank can be easily designed using the method.
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Kennedy, Patrick Michael. "Filter." 2005. http://wwwlib.umi.com/dissertations/fullcit/1426774.
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Thesis (M.Arch.)--State University of New York at Buffalo, 2005.Title from PDF title page (viewed on Feb. 1, 2006) Available through UMI ProQuest Digital Dissertations. Thesis adviser: Dennis A. Andrejko. Includes bibliographical references.
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Parikshith, B. C. "Integrated Approach To Filter Design For Grid Connected Power Converters." Thesis, 2009. https://etd.iisc.ac.in/handle/2005/973.
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Design of filters used in grid-connected inverter applications involves multiple constraints. The filter requirements are driven by tight filtering tolerances of standards such as IEEE 519-1992–IEEE Recommended Practices and Requirements for Harmonic Control in Electrical Power Systems and IEEE 1547.2-2008–IEEE Application Guide for IEEE Std 1547, IEEE Standard for Interconnecting Distributed Resources with Electric Power Systems. Higher order LCL filters are essential to achieve these regulatory standard requirements at compact size and weight. This objective of this thesis report is to evaluate design procedures for such higher order LCL filters.
The initial configuration of the third order LCL filter is decided by the frequency response of the filter. The design equations are developed in per-unit basis so results can be generalized for different applications and power levels. The frequency response is decided by IEEE specifications for high frequency current ripple at the point of common coupling. The appropriate values of L and C are then designed and constructed. Power loss in individual filter components is modeled by analytical equations and an iterative process is used to arrive at the most efficient design. Different combinations of magnetic materials (ferrite, amorphous, powder) and winding types (round wire, foil) are designed and tested to determine the most efficient design. The harmonic spectrum, power loss and temperature rise in individual filter components is predicted analytically and verified by actual tests using a 3 phase 10 kW grid connected converter setup.
Experimental results of filtering characteristics show a good match with analysis in the frequency range of interconnected inverter applications. The design process is stream-lined for the above specified core and winding types. The output harmonic current spectrum is sampled and it is established that the harmonics are within the IEEE recommended limits. The analytical equations predicting the power loss and temperature rise are verified by experimental results. Based on the findings, new LCL filter combinations are formulated by varying the net Lpu to achieve the highest efficiency while still meeting the recommended IEEE specifications. Thus a design procedure which can enable an engineer to design the most efficient and compact filter that can also meet the recommended guidelines of harmonic filtering for grid-connected converter applications is established.
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Parikshith, B. C. "Integrated Approach To Filter Design For Grid Connected Power Converters." Thesis, 2009. http://hdl.handle.net/2005/973.
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Design of filters used in grid-connected inverter applications involves multiple constraints. The filter requirements are driven by tight filtering tolerances of standards such as IEEE 519-1992–IEEE Recommended Practices and Requirements for Harmonic Control in Electrical Power Systems and IEEE 1547.2-2008–IEEE Application Guide for IEEE Std 1547, IEEE Standard for Interconnecting Distributed Resources with Electric Power Systems. Higher order LCL filters are essential to achieve these regulatory standard requirements at compact size and weight. This objective of this thesis report is to evaluate design procedures for such higher order LCL filters.
The initial configuration of the third order LCL filter is decided by the frequency response of the filter. The design equations are developed in per-unit basis so results can be generalized for different applications and power levels. The frequency response is decided by IEEE specifications for high frequency current ripple at the point of common coupling. The appropriate values of L and C are then designed and constructed. Power loss in individual filter components is modeled by analytical equations and an iterative process is used to arrive at the most efficient design. Different combinations of magnetic materials (ferrite, amorphous, powder) and winding types (round wire, foil) are designed and tested to determine the most efficient design. The harmonic spectrum, power loss and temperature rise in individual filter components is predicted analytically and verified by actual tests using a 3 phase 10 kW grid connected converter setup.
Experimental results of filtering characteristics show a good match with analysis in the frequency range of interconnected inverter applications. The design process is stream-lined for the above specified core and winding types. The output harmonic current spectrum is sampled and it is established that the harmonics are within the IEEE recommended limits. The analytical equations predicting the power loss and temperature rise are verified by experimental results. Based on the findings, new LCL filter combinations are formulated by varying the net Lpu to achieve the highest efficiency while still meeting the recommended IEEE specifications. Thus a design procedure which can enable an engineer to design the most efficient and compact filter that can also meet the recommended guidelines of harmonic filtering for grid-connected converter applications is established.
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Shih-Ken, Yang, and 楊世任. "Minimax Design of Digital Filters and Perfect-Reconstructioo Filter Banks." Thesis, 1998. http://ndltd.ncl.edu.tw/handle/40541120838292130400.
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博士國立臺灣科技大學
電子工程技術研究所
86
This dissertation presents several novel and efficient techniques for optimally designing one-dimensional (1-D) perfect-reconstruction (PR) filter banks, two-dimensional (2-D) FIR digital filters, and 2-D perfect- reconstruction and near-perfect-reconstruction parallelogram filter banks in the minimax senses. The proposed approaches are developed based on the affine and dual affine scaling variants of Karmarkar''s algorithm. As for the 1-D perfect-reconstruction digital filter banks, two novel techniques are proposed for designing PR filter banks with FIR analysis and synthesis filters having linear phase responses as well as low delay characteristics. The designed analysis and synthesis filters for both cases are optimal in the minimax sense subject to the perfect-reconstruction constraints. With regard to the design of 2-D digital filters, we propose design techniques for continuous and powers-of-two coefficients 2-D digital filters based on the minimax sense. The optimal continuous coefficient filters are first designed by an affine scaling variant of Karmarkar''s algorithm. Then a suboptimal powers-of-two coefficient filter is obtained by an efficient method from the optimal continuous filter coefficients. The design of 2-D parallelogram filter banks is also studied thoroughly. The linear-phase FIR analysis and synthesis optimal in minimax sense are considered. Two novel techniques for designing perfect-reconstruction and near-perfect-reconstruction 2-D parallelogram filter banks are presented. From the simulation examples demonstrated in each chapter of this dissertation, the effectiveness of the proposed design techniques for each considered design problem can be confirmed.
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Sun, Jhong-Min, and 孫中民. "Design of Dual-Band Bandpass Filter and Wide Stopband Filters." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/47180979286321478096.
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碩士國立中正大學
電機工程研究所
99
There are two parts in this thesis. The first part is design of a planar microwave dual-band bandpass filter. The structure of this dual-band bandpass filter is composed of an open-end coupled line and two parallel coupled lines with coupling feeding. Because the unequal even-mode and odd-mode phase velocity of the open-end coupled line, the interdigital capacitors at two ends of open-end coupled line are utilized to compensate the odd-mode phase velocity. Moreover, the added capacitive coupling between the input and output ports can move two transmission zeros at the passband skirts more closely. Then, two of single passband filters with different central frequencies are cascoded to achieve a dual-passband bandpass filter, and the J-inverter has been used to analyze this filter. In the second part, the planar microstrip bandpass filters with wide stopband are presented. The open-end coupled line, transmission line and short stub are the main structure of the wide stopband bandpass filter. By properly choosing electrical lengths of open-end coupled line, transmission line and short stub, the outband transmission zeros can be controlled to achieve a wide stopband. Moreover, the J-inverter can be used to analyze this filter. In addition, in order to increase the stopband bandwidth, two spur lines can be added into the input and output ports. All filters in this thesis are simulated with full-wave electromagnetic simulator, and these filters have been fabricated and measured. The matched results between electromagnetic simulation and measurement can demonstrate the availability of all proposed circuits.
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Chen, Tsuhan. "Multidimensional multirate filters and filter banks : theory, design, and implementation." Thesis, 1993. https://thesis.library.caltech.edu/3207/1/Chen_t_1993.pdf.
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Multidimensional (MD) multirate systems, which find applications in the coding and compression of image and video data, and in high definition television (HDTV) systems, have recently attracted much attention. Central to these systems is the idea of sampling lattices. The basic building blocks in an MD multirate system are the decimation matrix M, the expansion matrix L, and MD digital filters. When M and L are diagonal, most of the one-dimensional (1D) multirate results can be extended automatically, using separable approaches (i.e., separate operations in each dimension). Separable approaches are commonly used in practice due to their low complexity in implementation. However, nonseparable operations, with respect to nondiagonal decimation and expansion matrices, often provide more flexibility and better performance. Several applications, such as the conversion between progressive and interlaced video signals, actually require the use of nonseparable operations. For the nonseparable case, extensions of 1D results to the MD case are nontrivial. In this thesis, we will introduce some developments in these extensions. The three main results are: the design of nonseparable MD filters and filter banks derived from 1D filters, the commutativity of MD decimators and expanders and its applications to the efficient polyphase implementation of MD rational decimation systems, and the vector space framework for unifying MD filter bank and wavelet theory. In particular, properties of integer matrices like matrix fraction descriptions, coprimeness, the Bezout identity, etc., of which the polynomial versions are known in system theory, are used for the first time in the area of multirate signal processing.
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ElGarewi, Ahmed. "Analysis of algorithms for filter bank design optimization." Thesis, 2019. http://hdl.handle.net/1828/11131.
Full textAbstract:
This thesis deals with design algorithms for filter banks based on optimization. The design specifications consist of the perfect reconstruction and frequency response specifications for finite impulse response (FIR) analysis and synthesis filters. The perfect reconstruction conditions are formulated as a set of linear equations with respect to the analysis filters’ coefficients and the synthesis filters’ coefficients. Five design algorithms are presented. The first three are based on an unconstrained optimization of performance indices, which include the perfect reconstruction error and the error in the frequency specifications. The last two algorithms are formulated as constrained optimization problems with the perfect reconstruction error as the performance index and the frequency specifications as constraints. The performance of the five algorithms is evaluated and compared using six examples; these examples include uniform filter bank, compatible non-uniform filter bank and incompatible non-uniform filter bank designs. The evaluation criteria are based on distortion and aliasing errors, the magnitude response characteristics of analysis and synthesis filters, the computation time required for the optimization, and the convergence of the performance index with respect to the number of iterations. The results show that the five algorithms can achieve almost perfect reconstruction and can meet the frequency response specifications at an acceptable level. In the case of incompatible non-uniform filter banks, the algorithms have challenges to achieve almost perfect reconstruction.Graduate
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Liang, Zhi-Hong, and 梁志鴻. "Design of Timing-Error-Tolerant Digital Filters for Various Filter Transformations." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/4c2ycw.
Full textAbstract:
碩士國立東華大學
電機工程學系
102
In modern VLSI design, especially in system-on-chip, the number of transistors in a single chip keeps increasing thanks to the advance of chip manufacturing technology. However, as the feature size of modern chips shrinks, the circuits become more and more susceptible to noise, wire delay, and soft errors. One of these main problems is timing errors which are caused by process variation, device aging, etc. Such timing error problems can cause system failures. Hence, it is an important issue to solve the timing error problem while maintaining the performance of a chip. This thesis proposes various transformation designs for VLSI digital filters for tolerating multiple timing errors. We have developed a design methodology for VLSI digital filters, which can detect and tolerate multiple timing errors on-line. In order to achieve high performance of the digital filters, different transformations for various digital filter designs are applied. According to the design requirements, we choose the appropriate transformation for the filter in order to improve the performance, while it can still tolerate multiple timing errors. We have applied our techniques to two example digital signal filter designs, including a FIR filter and an IIR filter. Four examples for each circuit are studied and evaluated. We have implemented them using cell-based design flow on TSMC manufacturing technology. The implementation results show that our designs achieve high performance and tolerance of multiple timing errors for digital filters with reasonable cost.
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Hung, Wan-Ting, and 洪琬婷. "Bandstop Filters using Discrete-Time Notch-Filter Techniques and Their Applications." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/70723343095530253126.
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碩士國立臺灣科技大學
電子工程系
95
Parallel coupled-line microstrip filters have been widely used in many microwave and millimeter wave systems. The filters are usually degraded by the spurious response at twice the passband frequency. In this thesis, we propose a new method for the design of a compact bandstop filter. A bandstop filter of arbitrary bandwidth can be obtained by a cascade connection of multi-staged two-section open stubs with proper frequency scaling. At the last of the thesis, we apply the concept mentioned before to achieve the suppression of the second and third harmonics of the second-order Butterworth coupled-line bandpass filter. In this method, the system function of the second-order notch filter in Z-domain is studied first. The chain-scattering matrices of several transmission lines are then derived in the thesis. The design of the filter is finished with serial lines and two-section shunted open stubs. Experimental results are presented to illustrate the validity of this design method.
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Su, Wei. "Decomposition of high-order FIR filters and minimum-phase filter design." 2002. http://etd.utk.edu/2002/SuWei.pdf.
Full textAbstract:
Thesis (M.S.)--University of Tennessee, Knoxville, 2002.Title from title page screen (viewed Sept 25, 2002). Thesis advisor: L. Montgomery Smith. Document formatted into pages (viii, 135 p. : ill.). Vita. Includes bibliographical references (p. 66-68).