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Conception et mise en œuvre d'un procédé intensifié continu de microencapsulation par polycondensation interfaciale / Development of an intensified continuous process for microencapsulation by interfacial polycondensationTheron, Félicie 10 December 2009 (has links)
De nombreux produits encapsulés sont utilisés dans la vie quotidienne. Crèmes cosmétiques, peintures, et pesticides en sont quelques exemples. De nos jours, de plus en plus de technologies innovantes mettent en jeu des substances encapsulées. La microencapsulation a permis à de nouveaux « textiles intelligents » de voir le jour, tels que les textiles sur lesquels sont fixées des microcapsules qui libèrent un principe actif amincissant, odorant, hydratant ou encore répulsif pour les insectes. Les microcapsules sont des produits à fortes valeur ajoutée, dont les propriétés sont nombreuses, et délicates à maîtriser toutes à la fois. Si l'étape de formulation a pour objectif de trouver la recette optimale pour répondre le mieux possible au cahier des charges, le type de procédé de fabrication choisi doit garantir une production homogène dans le temps, sans écarts par rapports aux propriétés attendues. L'objectif de ces travaux est de proposer une alternative continue aux procédés batch traditionnellement mis en œuvre pour l'encapsulation par polycondensation interfaciale, coûteux en termes d'investissement et de frais de fonctionnement. L'encapsulation par polycondensation interfaciale est constituée d'une étape d'émulsification suivie d'une étape réactive. Nous proposons un procédé découplant ces deux étapes grâce à deux technologies adaptées aux contraintes hydrodynamiques respectives de chaque étape. Cette étude est réalisée sur la base d'un système modèle espèce encapsulée / membrane polymérique. L'étape d'émulsification est réalisée en mélangeurs statiques en régime turbulent. Des mesures de pertes de charge en écoulements monophasiques ont permis de mettre en évidence l'apparition de ce régime et d'établir des corrélations représentant ces pertes de charge a travers l'emploi des nombres adimensionnels que sont le nombre de Reynolds et le facteur de friction. Concernant l'émulsification, nous évaluons l'influence de différents paramètres sur les performances de l'opération en termes de tailles de gouttes obtenues en fonction du coût énergétique. Nous comparons également les performances de trois designs de mélangeurs statiques commercialisés par la société Sulzer, et corrélons les résultats obtenus en termes de diamètres moyens de Sauter en fonction des nombres de Reynolds et de Weber. L'étape réactive est tout d'abord mise en œuvre en réacteur agité afin d'étudier la cinétique de la réaction, et d'acquérir des temps de réactions qui permettent par la suite de dimensionner le réacteur continu. Enfin cette étape est réalisée dans deux types de réacteurs continus : le réacteur Deanhex, développé et étudié par Anxionnaz et al. (2009), ainsi qu'un réacteur tubulaire en serpentin. Cette dernière étude consiste d'une part à valider le passage au continu à travers la conservation de la granulométrie des gouttelettes de l'émulsion durant la réaction, et la conservation de la vitesse apparente de la réaction. Enfin, les conditions hydrodynamiques favorables présentées par les réacteurs continus permettent d'apporter de nouvelles voies d'intensification au procédé en augmentant d'une part la concentration en capsules dans le réacteur, et en s'affranchissant de l'emploi du tensioactif utilisé pour stabiliser les gouttes de l'émulsion. Ce procédé, proposé pour la production en continu de microcapsules, offre une amélioration en termes de qualité du produit et de coût par rapport aux procédés traditionnels en batch mis en œuvre dans l'industrie. / The aim of the present work is to propose a continuous alternative to batch processes classically used to carry out encapsulation by interfacial polycondensation that represent high investment and working costs. Encapsulation by interfacial polycondensation consists in an emulsification step followed by a reactive step. We propose here a process decoupling these two steps using technologies well adapted to hydrodynamic issues of each step. This study is realised on the basis of model system. The emulsification step is carried out in static mixers under turbulent flow. Pressure drop measurements in single-phase flow enable to highlight this flow regime and to establish correlations representing these pressure drops in terms of dimensionless numbers: the Reynolds number and the friction factor. About emulsification we evaluate the influence of different parameters on the operation performances in terms of mean droplets size as a function of energy cost. We compare the performances of three different Sulzer static mixers and correlate results obtained in terms of Sauter mean diameter as a function of Reynolds and Weber numbers. The reactive step has been first carried out is stirred tank in order to study the reaction kinetics and to acquire reaction times necessary to design continuous reactors. Finally this step has been realised using two continuous reactors: the Deanhex reactor (Anxionnaz et al., 2009) and a coiled tube reactor. This last study consists first in validating the continuous process through the conservation of the emulsion size distribution during encapsulation and the conservation of the apparent kinetics. Finally the favourable hydrodynamic conditions presented by continuous reactors offer new ways of intensification to the process. In fact it is possible to increase the microcapsule concentration in the reactor and to work without surfactant to stabilize the emulsion. This continuous process for microcapsules production offers improvements in terms of product quality and working costs compared to traditional batch process used in the industry
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Modelovanje "cross-flow" mikrofiltracije suspenzija kvasca primenom koncepta neuronskih mreža i postupka odzivne površine / Cross-flow microfiltration modelling of yeast suspension by neural networks and response surface methodologyJokić Aleksandar 09 July 2010 (has links)
<p>Cilj ovog rada je ispitivanje mogućnosti primene koncepta neuronskih mreža i postupka odzivne površine za modelovanje cross-flow mikrofiltracije suspenzija kvasca. Drugi cilj je bio ispitivanje poboljšanja procesa primenom Kenics statičkog mešača kao promotora turbulencije. Primena statičkog mešača ispitana je i sa energetskog stanovišta, a ne samo sa aspekta povećanja fluksa permeata. Svi eksperimenti izvedeni su u uslovima recirkulacije i koncentrisanja napojne suspenzije.</p><p>Dobijeni rezultati ukazuju da se poboljšanje mikrofiltracije može se ostvariti primenom statičkog mešača bez primene dodatne opreme. Tokom eksperimentalnog rada porast fluksa iznosio je između 89,32% i 258,86% u uslovima recirkulacije napojne suspenzije u zavisnosti od odabranih eksperimentalnih uslova, dok je u uslovima koncentrisanja napojne suspenzije porast fluksa imao vrednosti od 100% do 540% u istom eksperimentalnom opsegu.</p><p>Koncept neuronskih mreža daje veoma dobre rezultate fitovanja posmatranih odziva.<br />Pored primene ovog koncepta ispitana je i mogućnost procene uticaja pojedinih<br />eksperimentalnih promenljivih na odzive primenom jednačine Garsona i metode jačine sinapsi koje povezuju neurone. Rezulati ovog ispitivanja u saglasnosti su sa regresionom analizom.</p><p>Za detaljniju analizu uticaja eksperimentalnih promenljivih na posmatrane odzive primenjen je postupak odzivne površine funkcije. Prvi korak u ovom segmentu istraživanja bio je određivanje uticaja srednjeg prečnika pora membrane na proces mikrofiltracije. Najbolji rezultati dobijeni su za membranu srednjeg prečnika 200 nm, pošto kod većih prečnika pora dolazi do izraženijeg unutrašnjeg prljanja koje rezultuje manjim vrednostima fluksa permeata tokom proces mikroflitracije.</p><p>Dalja istraživanja usmerena su na ispitivanje uticaja pojedinih eksperimentalnih promenljivih ali i njihovih interakcija za odabranu membranu (srednji prečnik pora 200 nm). Rezultati fitovanja eksperimentalnih podataka dobijeni za jednu membranu bolji su u poređenju sa rezultatima kada su fitovani eksperimentalni rezultati za sve tri korištene membrane. Sa energetske tačke gledišta primećeno je da je najbolje raditi u umerenom opsegu protoka napojne suspenzije. Kao kranji cilj primene postupka odzivne površine urađena je optimizacija vrednosti eksperimentalnih promenljivih, primenom postupka željene funkcije. Optimalni uslovi rada dobijeni u uslovima recirkulacije napojene suspenzije su transmembranski pritisak 0,2 bara, koncentracija napojne suspenzije 7,54 g/l i protok 108,52 l/h za maksimalne vrednosti specifične redukcije potrošnje energije. Sa sruge strane u uslovima koncentrisanja napojne suspenzije eksperimentalne promenljive imale su vrednosti transmembranski pritisak 1 bar, koncentracija napojne suspenzije 7,50 g/l i protok 176 l/h za maksimalne vrednosti specifične redukcije potrošnje energije.</p> / <p>The aim of this work was to investigate<br />possibilities of applying neural network and<br />response surface methodology for modeling crossflow<br />microfiltration of yeast suspensions. Another<br />aim was to investigate the improvement of process<br />using Kenics static mixer as turbulence promoter.<br />Experimental work was performed on 200, 450 and<br />800 nm tubular ceramic membranes. The use of<br />static mixer was also examined from an energetic<br />point of view not only its influence on permeate<br />flux. All experiments were done in recirculation and<br />concentration mode.<br />The results clearly show that the<br />improvement of cross-flow microfiltration of yeast<br />suspensions performances can be done with static<br />mixer without any additional equipment. In<br />experimental work, flux increase had values<br />between 89.32% and 258.86% for recirculation of<br />feed suspension depending on experimental values<br />of selected variables while in concentration mode<br />this improvement was in range between 100% and<br />540% for the same range of experimental variables.<br />Neural networks had excellent predictive<br />capabilities for this kind of process. Besides<br />examination of predictive capabilities of neural<br />networks influence of each variable was examined<br />by applying Garson equation and connection<br />weights method. Results of this analysis were in<br />fairly good agreement with regression analysis.<br />For more detailed analysis of variables influence on<br />the selected responses response surface<br />methodology was implemented. First step was to<br />investigate the influence of membrane pore size on<br />the process of microfiltration. The results suggested<br />that the best way to conduct microfiltration of yeast<br />suspensions is by using the membrane with mean<br />pore size of 200 nm, because bigger mean pore size<br />can lead to more prominent internal fouling that<br />causes smaller flux values.<br />Further investigations of microfiltration<br />process were done in order to investigate influences<br />of variables as well as their interactions and it was<br />done for the membrane with pore size of 200 nm.<br />Results for this membrane considering regression<br />analysis were considerably better compared with<br />results obtained for modeling all three membranes.<br />From the energetic point of view it was concluded<br />that it is optimal to use moderate feed flows to<br />achieve best results with implementation of static<br />mixer.<br />As the final goal of response surface<br />methodology optimization of process variables was<br />done by applying desirability function approach.<br />Optimal values of process variables for<br />recirculation of feed suspension were<br />trasmembrane pressure 0.2 bar, concentration 7.54<br />g/l and feed flow 108.52 l/h for maximal values of<br />specific energy reduction. On the other side for<br />concentration of feed suspension these variables<br />had values of 1 bar, 7.50 g/l and 176 l/h</p>
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Separacija nesaharoznih jedinjenja iz međufaznih produkata kristalizacije šećera ultrafiltracijom / SEPARATION OF NON-SUCROSECOMPOUNDS FROM THE INERMEDIATEPRODUCTS OF SUGAR CRYSTALLIZATIONUSING ULTRAFILTRATIONŠereš Zita 22 February 2008 (has links)
<p>U radu su ispitane mogucnosti separacaije<br />nesaharoznih jedinjenja ultrafiltracijom iz rastvora<br />B i C šecera sadržaja suve materije 60 i 30 <sup>o</sup>Bx.<br />Eksperimentalna ispitivanja su izvedena na<br />keramickim membrana sa otvorom pora od 20 i 5<br />nm, bez i sa primenom statickog mešaca kao<br />promotora turbulencije. Tokom recirkulacije i<br />koncentrovanja napojne smeše pracen je uticaj<br />nezavisno promenljivih (transmembranskog<br />pritiska, protoka, temperature i vremena trajanja<br />procesa) na fluks, boju, mutnocu i kvocijent<br />cistoce permeta. Ispitan je uticaj statickog mešaca<br />na prljanje membrane, na potrošnju energije i<br />smanjenja proizvodnih troškova. Eksperimentalni<br />rezultati su jasno pokazali da se najveca razlika u<br />vrednosti fluksa permeata rastvora B šecera dobija<br />kada se uporedi nacin rada bez i sa upotrebom<br />mešaca. Ta razlika iznosi 30% na 80<sup>o</sup>C, odn. 65%<br />kada se temperatura održava na 70<sup>o</sup>C. Pri<br />ultrafiltraciji rastvora C šecera, koji sadrži<br />mnogostruko vecu kolicinu nesaharoznih<br />jedinjenja, registruje se brža koncentraciona<br />polarizacija, te se pri istim uslovima postiže za<br />70% manji fluks od fluksa permeata rastvora B<br />šecera. Sadržaj saharoze permeata i retentata se ne<br />menja tokom ultrafiltracije, nema merljive<br />retencije saharoze, što je presudno za buducu<br />primenu ovog separacionog postupka u industriju<br />šecera. Dekoloracija rastvora B šecera bez<br />upotrebe mešaca ?? na nivou 40%, ? postiže se na<br />pritisku nižem od 6 bar i protoku od 250 L/h.<br />Upotrebom mešaca se efekat dekoloracije<br />poboljšava za oko 60%, i to pri protoku ispod 200<br />L/h. Izdvajanje bojenih materija pri ultrafiltraciji<br />rastvora C šecera je prividno manje efikasno, jer<br />ne prelazi vrednost od 25% racunato na napojnu<br />smešu, mada se u apsolutnim vrednostima iz<br />rastvora B i C šecera izdvoji približno ista kolicina<br />bojenih materija (900 IJ). Ultrafiltracijom se<br />mutnoca napojne smeše redukuje za 85%.<br />Ispitivanja prljanja membrane pri ultrafiltraciji su<br />pokazala da koncentraciona polarizacija i<br />formiranje sloja sastavljenog od nesaharoznih<br />jedinjenja na površini membrane predstavljaju<br />dominantan udeo ukupnog hidraulicnog otpora. U<br />membrani sa otvorom pora 20 nm, tokom<br />ultrafiltracije meduproizvoda f?ze kristalizacije,<br />otpor poraste usled prljanja za 20 – 50 puta, a u<br />membrani sa otvorom pora 5 nm za 100 – 300 puta<br />u odnosu na otpor ciste membrane. Korišcenje<br />mešaca je opravdano u intervalu gubitaka<br />hidraulicke snage od 0 – 7 W, jer se time postiže<br />povecanje fluksa i do 60%. Pri vecim gubicima<br />hidraulicne snage, odn. pri vecim brzinama<br />proticanja, nivo turbulencije u praznoj cevi je<br />znacajan, tako da se i bez upotrebe mešaca<br />registruju vece vrednosti fluksa. Povecanje stepena<br />koncentrovanja napojne smeše sa 1,0 na 1,2 prati<br />smanjenje ukupnih prizvodnih troškova u opsegu<br />od 30 – 77% kada se proces ultrafiltracije realizuje<br />uz upotrebu mešaca.</p> / <p>This work presents the study of possibility to<br />separate of non-sucrose compounds from B and C<br />sugar solutions, with a dry matter content of 60 and<br />30 oBx by ultrafiltration. Experimental<br />investigations were performed on ceramic tubular<br />20 and 5 nm pore diameters membranes, with and<br />without kenics static mixer as turbulence promoter.<br />The influence of independent parameters<br />(transmembrane pressure, flow rate, temperature<br />and ultrafiltration time duration) on permetate flux,<br />colour, turbidity and purity during feed<br />recirculation and feed concentration were<br />examined. The efficiency of static mixer was<br />investigated on membrane fouling, on energy<br />consumption and on economical calculations. The<br />experimental results showed that, the greatest flux<br />difference of B sugar solution was obtained when<br />the operation mode was with a static mixer in<br />comparation to the operation mode without one,<br />showing 30% difference at temperature 80 oC and<br />65% at 70 oC. While ultrafiltering the C sugar<br />solution, which contains more non-sucrose<br />compounds, a faster concentration polarization was<br />noticed, thus at the same working conditions 70%<br />less flux was reached in comparison with to the B<br />sugar solution permeate flux. The permeate and<br />retentate sugar content did not changed during<br />ultrafiltration, there is no measurable retention of<br />sucrose, which is important for the implementation<br />of this type of separation into sugar industry. The<br />decoloration of B sugar solution without static<br />mixer is 40%, and can be reached at<br />transmembrane pressure bellow 6 bar and flow rate<br />of 250 L/h. By using a static mixer the decoloration<br />effect is improved for 60%, when flow rate is held<br />bellow 200 L/h. The separation of coloured<br />compounds during ultrafiltration of C sugar<br />solution is apparently less efficient since the value<br />did not reach 25% calculated on feed, even though<br />measured in absolute values the same level of<br />coloured compounds was separated from B and C<br />sugar solution (900 IU). The turbidity of B and C<br />solution was reduced by ultrafiltration for 85%.<br />The examinations of membrane fouling during<br />ultrafiltration showed that the concentration<br />polarization and formation of a non-sucrose<br />compound layer on the membrane surface are<br />dominant parts of the total hydraulic resistance.<br />During ultrafiltration of intermediate products of<br />sugar crystallization using 20 nm pore membrane<br />diameter the resistance increased for 20 – 50 times<br />due to fouling. Using a 5 nm pore diameter<br />membrane the resistance increased for 100 – 300<br />times comparing to clean membrane. The use of<br />static mixer is justified when 0 – 7 W loss of<br />hydraulic power was determined, because in that<br />interval a 60% flux increase was detected. At<br />higher levels of hydraulic power loss, and at higher<br />values of flow rates the turbulency in empty tubular<br />membrane is significant, so even without using<br />static mixers higher values of flux are detected.<br />When a static mixer was used with the increase of<br />volume concentration ratio from 1,0 to 1,2 the total<br />production costs decreased in a range of 30 – 77%.</p>
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Návrh ohřevu vyhnívací nádrže / The design of the digestion tank heatingCupra, Šimon January 2017 (has links)
The diploma thesis is focused on the design of heating of the digestion tank, which is part of the waste water purification process and where the process of sludge digestion takes place. Anaerobic digestion (methanisation) is a process main goal of which is the hygienesation of incoming sludge and related biogas production. In the first part the reader is introduced to the subject of mixed and heated industrial vessels. In the second part of the thesis thermo-hydraulic calculation of the heating process is carried out in case the vessel is agitated and in case the agitation is not applied. The next part of the thesis describes the procedure for creating a calculation tool, which is later used to solve two sample problems. The last part describes the experimental measurement of the pumping characteristics of the agitator.
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Vstupní část kvadraturního přijímače pro pásmo UHF / UHF band front-end of quadrature receiverTiller, Jakub January 2012 (has links)
The object of this master's thessis is study and description of RF circuits, which are used for receiveing. This work is also aimed to design this circuits and their simulation in Ansoft Designer software. Focus is placed to the standard parameters of receiving technology. The description of amplifier design is presented in this work. Parameters of this amplifier are optimalized to low noise figure. Frequency multiplier designs are included in this project.
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Spektrální analyzátor do 500 MHz / Spectrum Analyzer up to 500 MHzČada, David January 2015 (has links)
This project deals with design and realization of the spectrum analyser using double superheterodyne topology with frequency range up to 500MHz. This work solves hardware blocks like phase lock loops, intermediate frequency filters, saw filter, crystal filter, logarithmic detector. Content of work is also design description and tuning of spectrum analyzer parts.
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Konstrukční návrh průběžného mísiče o výkonu 3-5 tun/hod / The design of sand mixer with output range 3-5 TPHHaluza, Lukáš January 2012 (has links)
The subject of this diploma thesis is engineering design of the continuous mixer with output range 3-5 TPH. Mixer is instrumental to mixing sand mixture intended to non-permanent sand forms in foundry. Proposed construction has to fulfill the specified functional requirements and parameters. Parts of solution are also necessary analytical and FEA calculations.
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Subharmonické směšovače pro mikrovlnná pásma / Subharmonic Mixers for Microwave BandsKintr, Jindřich January 2016 (has links)
The task of this master’s thesis is design and implementation subharmonic mixer for the microwave band. Subharmonic mixer is based on the principle of antiparallel diode. In the first two parts are theoretically described mixers (subharmonic mixer) and topology suitable for implementation. Another work describes the design subharmonic mixer. The proposal is implemented in the program Ansoft designer. DPS is created in Eagle or in Ansoft Designer. The mixer is designed and implemented first on the lower frequency and consequently at higher frequencies (24,048 GHz and 47,088 GHz). Work also includes the measurement results of the mixer.
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Subharmonické směšovače pro mikrovlnná pásma / Subharmonic Mixers for Microwave BandsKintr, Jindřich January 2016 (has links)
The task of this master’s thesis is design and implementation subharmonic mixer for the microwave band. Subharmonic mixer is based on the principle of antiparallel diode. In the first two parts are theoretically described mixers (subharmonic mixer) and topology suitable for implementation. Another work describes the design subharmonic mixer. The proposal is implemented in the program Ansoft designer. DPS is created in Eagle or in Ansoft Designer. The mixers are designed and implemented first on the lower frequency and consequently at higher frequencies (24,048 GHz and 47,088 GHz). Work also includes the measurement results of the mixers.
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Schaltungen zur Frequenzumsetzung für drahtlose Übertragungssysteme im MillimeterwellenbereichRieß, Vincent 14 May 2021 (has links)
Diese Arbeit beschreibt den Entwurf, die Analyse und die Verifikation von integrierten Schaltungen zur Frequenzumsetzung für drahtlose Übertragungssysteme im Millimeterwellenbereich. Bei der Beschreibung der zur Verfügung stehenden Halbleitertechnologien und der Aufbau- und Verbindungstechniken wird deutlich, dass parasitäre Widerstände, Kapazitäten und Induktivitäten sämtlicher Verbindungen Verluste und Reflexionen verursachen, die mit der Signalfrequenz ansteigen. Dies motiviert die Reduktion der Signalfrequenz zur Verringerung dieser Verluste, soweit wie dies in einem Millimeterwellensystem möglich ist.
Neben den in drahtlosen Übertragungssystemen ohnehin erforderlichen Mischern zur Modulation und Demodulation werden in dieser Arbeit auch Frequenzmultiplizierer vorgestellt. Mit diesen Schaltungen ist es möglich, das hochfrequente Trägersignal direkt neben den Mischern zu erzeugen und mit möglichst kurzen Leitungen anzuschließen, sodass die parasitären Verluste dieser Verbindung sowie die Reflexionen minimal werden. Mit Ausnahme der Verbindungen zu den Antennen kann dadurch die Frequenz der restlichen extern anzuschließenden Signale, nämlich des zu übertragenden Basisbandsignals und des subharmonischen LO-Signals, wesentlich verringert werden, wodurch die Verluste insgesamt reduziert werden.
In dieser Arbeit werden dafür zwei Frequenzverdoppler und ein Frequenzversechsfacher vorgestellt, die jeweils mit einer Eingangsfrequenz im Bereich um 30 GHz Ausgangssignale bei 60 GHz bzw. bei 180 GHz erzeugen. Diese drei Schaltungen wurden mit einem Schwerpunkt auf der Unterdrückung unerwünschter Harmonischer und einer gleichzeitig effizienten Erzeugung der gewünschten Harmonischen entworfen. Damit konnte der Stand der Technik für BiCMOS-Frequenzmultiplizierer mit einer Ausgangsfrequenz von bis zu 210 GHz verbessert werden. Sowohl hinsichtlich der absoluten DC-Leistung des Frequenzversechsfachers von lediglich 63 mW, als auch bezüglich der Effizienz (PAE) von 0,28 %, der Verstärkung von 10 dB und der Unterdrückung unerwünschter Harmonischer von bis zu 35 dB sind die erzielten Ergebnisse außerdem besser als von einigen Schaltungen aus leistungsfähigeren III-V-Halbleiterprozessen.
Passend zur Mittenfrequenz von 180 GHz am Ausgang des Frequenzversechsfachers, die auch die Mittenfrequenz des IEEE G-Bands ist, werden außerdem integrierte Aufwärts- und Abwärtsmischer entwickelt, die auf der für Kommunikationssysteme vergleichsweise wenig beachteten Sechstor-Architektur basieren. Die Vorteile der Sechstor-Architektur wurden zuvor bereits bei niedrigeren Frequenzen sowohl mit integrierten als auch mit diskret aufgebauten Schaltungen demonstriert. Ein Ziel dieser Arbeit ist die darauf aufbauende Entwicklung und Untersuchung von integrierten I-Q-Mischern mit dieser Architektur für drahtlose Kommunikationssysteme bei 180 GHz in einem 130 nm-BiCMOS-Prozess. Dafür werden geeignete Detektoren und Reflektoren präsentiert, mit denen die Implementierung in diesem Frequenzbereich möglich ist. Mit den erzielten Ergebnissen konnte jeweils der Stand der Technik für integrierte Sechstor-Aufwärts- und -Abwärtsmischer verbessert werden: Im Fall der Sechstor-Aufwärtsmischer stellen die durchgeführten Messungen die erste Verifikation dieser Architektur im Millimeterwellenbereich dar. Auch im Fall der Abwärtsmischer ist die entworfene Schaltung die erste Realisierung bei einer Mittenfrequenz von über 120 GHz. Die erzielten Ergebnisse zeigen, dass die Sechstor-Architektur im Millimeterwellenbereich für die Anwendung in drahtlosen Übertragungssystemen geeignet ist. Hinsichtlich der HF-Eigenschaften sind die erzielten Ergebnisse vergleichbar mit oder besser als solche, die mit technologisch aufwendigeren und oftmals energieintensiveren Schalter-Mischern, wie z.B. den Gilbert-Mischern, erreicht werden. Darüber hinaus wird anhand von mathematischen Schaltungsanalysen gezeigt, dass sich diese Mischerarchitektur ebenfalls durch ihre gute analytische Modellierbarkeit auszeichnet. Selbst mit stark idealisierten und vereinfachten Modellen kann der Mischgewinn bei 180 GHz mit einer Abweichung zur Messung und zur Simulation von lediglich rund 5 dB berechnet werden.:Kurzfassung
Abstract
Symbolverzeichnis
Vorveröffentlichungen
1. Einleitung
2. Fertigungsprozesse für Schaltungen im Millimeterwellenbereich
2.1. Halbleitertechnologien
2.2. Aufbau- und Verbindungstechnik
2.3. Reduktion von Verlusten mittels Frequenzumsetzung
3. Frequenzmultiplizierer
3.1. Frequenzverdoppler mit Polyphasenfilter
3.2. Frequenzverdoppler mit aktivem und passivem Balun
3.3. Frequenzversechsfacher
3.4. Anwendung in einem Millimeterwellensystem
4. Mischer
4.1. Sechstor-Interferometer
4.2. Sechstor-Abwärtsmischer
4.3. Sechstor-Aufwärtsmischer
5. Zusammenfassung und Ausblick
A. Betragsberechnungen der auslaufenden Wellen des Sechstors
B. Lösung der nichtlinearen Differenzialgleichung
C. Differenzen der Quadrate und Kuben harmonischer Summen
Literaturverzeichnis
Danksagung / In this thesis the design, analysis and verification of integrated circuits for wireless communication systems operating at millimeter waves is presented. During a review of the available manufacturing processes for integrated circuits, printed circuit boards, and interconnects, problems associated with these techniques are identified. Parasitic elements, such as resistors, capacitors, and inductors introduce losses that increase with the signal frequency. This motivates the reduction of the signal frequency wherever possible, so as to reduce these frequency-dependent losses.
To achieve this, millimeterwave up- and downconverting mixers, which are anyway required in wireless systems for the modulation and demodulation of an rf carrier signal, and frequency multipliers for generation of those carrier signals are presented in this thesis. With the frequency multipliers it is possible to generate the carrier signals as spatially close to the mixers as possible, reducing the required length of the connection and the losses and reflecions associated with it. Two frequency doublers and a frequency sixtupler were designed for the conversion of input signals at 30 GHz to output signals at 60 GHz and at 180 GHz, respectively. The designs are focused on an energy-efficient generation of the desired harmonic and a large suppression of other undesired harmonics. In this way, the demonstrated results for the frequency sixtupler at 180 GHz improve the state-of-the-art for both BiCMOS and III-V circuits in terms of power consumption, power added efficiency (PAE), conversion gain and harmonic suppression. With the output frequency at up to 210 GHz and with a dc power consumption of 63 mW, a conversion gain of 10 dB, a PAE of 0.28 %, and a harmonic suppression of 35 dB is reached.
Matching the output frequency of the sixtupler, two quadrature mixers operating at 180 GHz are presented. They are based on the six-port technique, which offers some promising features at millimeter wave frequencies, but is still not very popular for the application in integrated communication systems. Some research has already been conducted on six-port receivers for radar and communication systems operating at lower frequencies, both as integrated circuits and on printed circuit boards. In the case of six-port downconversion mixers, competetive results with discrete III-V diodes and transistors on printed circuit boards were demonstrated, but very little research on integrated realizations has been published to date. One goal of this thesis is therefore to design integrated six-port mixers at 180 GHz and investigate this architecture for the quadrature up- and downconversion in communication systems. Suitable active detectors and reflectors are proposed to enable the implementation of the six-port technique at these frequencies.
In this way, the first implementation of the six-port technique for the upconversion at millimeterwave frequencies is demonstrated. For the downconversion, the rf center frequency at 180 GHz is the highest among six-port implementations to date. The results in terms of rf performance compare well against state-of-the-art switching mixers, such as Gilbert cells. Moreover, the six-port architecture is found to be much simpler in terms of the circuit complexity and it enables the circuit analysis using only simple and idealistic models. With such models, the conversion gain at 180 GHz can be calculated with an error of only about 5 dB. In its minimal realization, a quadrature mixer with a very low dc power consumption can be designed. This makes the six-port technique increasingly attractive as the rf frequency is increased and switching mixers consume a higher dc and rf power.:Kurzfassung
Abstract
Symbolverzeichnis
Vorveröffentlichungen
1. Einleitung
2. Fertigungsprozesse für Schaltungen im Millimeterwellenbereich
2.1. Halbleitertechnologien
2.2. Aufbau- und Verbindungstechnik
2.3. Reduktion von Verlusten mittels Frequenzumsetzung
3. Frequenzmultiplizierer
3.1. Frequenzverdoppler mit Polyphasenfilter
3.2. Frequenzverdoppler mit aktivem und passivem Balun
3.3. Frequenzversechsfacher
3.4. Anwendung in einem Millimeterwellensystem
4. Mischer
4.1. Sechstor-Interferometer
4.2. Sechstor-Abwärtsmischer
4.3. Sechstor-Aufwärtsmischer
5. Zusammenfassung und Ausblick
A. Betragsberechnungen der auslaufenden Wellen des Sechstors
B. Lösung der nichtlinearen Differenzialgleichung
C. Differenzen der Quadrate und Kuben harmonischer Summen
Literaturverzeichnis
Danksagung
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