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1
Zhang, Guidong [Verfasser]. "Impedance networks matching mechanism and design of impedance networks converters / Guidong Zhang." Hagen : Fernuniversität Hagen, 2015. http://d-nb.info/1079393064/34.
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Sun, Yichuang. "Analysis and synthesis of impedance matching networks and transconductance amplifier filters." Thesis, University of York, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.297262.
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Song, Keum Su. "Non-Foster Impedance Matching and Loading Networks for Electrically Small Antennas." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1308313555.
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TaheriNejad, Nima. "Power line communications in vehicles : channel measurements and impedance matching networks." Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/52749.
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In today's Electric Vehicles (EVs) and conventional Combustion Engine Vehicles(CEVs), data communication between electronic control units is accomplished by sending communication signals over dedicated wires. The space requirement, weight, and installation costs for these wires can become significant, especially in electric vehicles of the future, which are highly sophisticated electronic systems. This has motivated research and development activities in the area of Vehicular Power Line Communication (VPLC). VPLC systems reuse power wires inside a vehicle for data communication
purposes. Thus, they eliminate the need for extra wires dedicated to communication.
However, there are several impediments to overcome in order to achieve a reliable and robust VPLC. Many of these challenges originate from inherent
properties of current wirings in vehicles, which are not designed with communication in mind. Therefore, to develop suitable data transmission
equipments, a good understanding of the communication channel characteristics is essential. Considering the importance of proper characterization as a first step towards the design and deployment of VPLC systems, in this work, we have tried to contribute to the available body of knowledge on channel characterization for VPLC in EVs and CEVs. As tangible contributions, we present methodology and results of two measurement campaigns in this thesis. The main outcomes of this part of our research are quantitative statements about Channel Transfer Functions and Access Impedance for two vehicles and discussions of our results in the context of VPLC system design.
Building on the results of these measurements, an adaptive impedance matching system is designed to improve the power transmission between VPLC devices and the vehicular power line network, and consequently improve the Signal-to-Noise Ratio (SNR) of the communication system. The adaptive impedance matching system is first behaviorally described in VHDL-AMS and simulated using Cadence™ and then for each unit a circuit design compatible for implementation on an Integrated Circuit (IC) platform is suggested.
Tested against the challenges of VPLC observed in our measurement campaigns, the proposed system proved to be capable of significantly improving the reliability of communication over power wires in vehicle.Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
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Chen, Wei-Chuan. "A Multi-Channel, Impedance-Matching, Wireless, Passive Recorder for Medical Applications." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1555661316375242.
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Alibakhshikenari, M., B. S. Virdee, L. Azpilicueta, C. H. See, Raed A. Abd-Alhameed, A. A. Althuwayb, F. Falcone, I. Huyen, T. A. Denidni, and E. Limiti. "Optimum power transfer in RF front end systems using adaptive impedance matching technique." Nature Publishing Group, 2021. http://hdl.handle.net/10454/18508.
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YesMatching the antenna’s impedance to the RF-front-end of a wireless communications system is challenging as the impedance varies with its surround environment. Autonomously matching the antenna to the RF-front-end is therefore essential to optimize power transfer and thereby maintain the antenna’s radiation efficiency. This paper presents a theoretical technique for automatically tuning an LC impedance matching network that compensates antenna mismatch presented to the RF-front-end. The proposed technique converges to a matching point without the need of complex mathematical modelling of the system comprising of non-linear control elements. Digital circuitry is used to implement the required matching circuit. Reliable convergence is achieved within the tuning range of the LC-network using control-loops that can independently control the LC impedance. An algorithm based on the proposed technique was used to verify its effectiveness with various antenna loads. Mismatch error of the technique is less than 0.2%. The technique enables speedy convergence (< 5 µs) and is highly accurate for autonomous adaptive antenna matching networks.
This work is partially supported by RTI2018-095499-B-C31, Funded by Ministerio de Ciencia, Innovación y Universidades, Gobierno de España (MCIU/AEI/FEDER,UE), and innovation programme under grant agreement H2020-MSCA-ITN-2016 SECRET-722424 and the financial support from the UK Engineering and Physical Sciences Research Council (EPSRC) under grant EP/E022936/1.
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Kilic, Ozgehan. "Defected Ground Structure And Its Applications To Microwave Devices And Antenna Feed Networks." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12612415/index.pdf.
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This thesis reports the analysis of the rectangular shaped defected ground structure
(RS-DGS) and the application of the structure on some microwave devices. DGS is analyzed
in terms of its superior properties, which enables the designers to easily realize
many kind of microwave devices which are impossible to achieve with the standard applications.
Within the scope of this thesis, the focus is on the rectangular shaped DGS
and its characteristic properties. The basic slow wave and high impedance characteristics
are utilized in the design of some microwave devices. The design is carried on at the two
different frequency bands: X-band and Ka band, centering at 10 GHz and 35 GHz, respectively.
Finally, using the high impedance property and the coupling between the
defects, a wide band 1 : 4 beam forming network is designed and implemented at
10 GHz.
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Kamprath, Richard Alan. "Impedance matching techniques for ethernet communication systems." Texas A&M University, 2003. http://hdl.handle.net/1969.1/5856.
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In modern local area networks, the communication signals sent from one
computer to another across the lines of transmission are degraded because of reflection at
the receiver. This reflection can be characterized through the impedances of the
transmitter and the receiver, and is defined by the Institute of Electrical and Electronic
Engineers (IEEE) as the S11 return loss. The specifications for S11 return loss in Gigabit
Ethernet are given in terms of magnitude only in the IEEE 802.3 guidelines. This does
not fully take into account, however, the effects of frequency dependant impedances
within the bandwidth of interest. With a range of 30% error in the category 5, or CAT5,
transmission line impedance used in this specification and no further requirements for
individual components within the Gigabit Ethernet port, such as the RJ45 magjack or the
physical layer, the system can easily be out of tolerance for return loss error. A simple
impedance matching circuit could match the CAT5 cable to the physical layer such that
the return loss is minimized and the S21 transmission is maximized.
The first part of the project was commissioned by Dell Computer to characterize
the return loss of all of its platforms. This thesis goes further in the creation of a system
that can balance these two impedances so that the IEEE specification failure rate is
reduced with the lowest implementation cost, size, power and complexity. The return
loss data were used in the second phase of the project as the basis for component ranges
needed to balance the impedance seen at the front of the physical layer to the CAT5 transmission line. Using the ladder network theory, an impedance matching circuit was
created that significantly reduced the S11 return loss in the passband of the equivalent
ladder network. To manage this iterative process, a control loop was also designed.
While this system does not produce the accuracy that a programmable finite impulse
response (FIR) filter could, it does improve performance with relatively minimal cost,
power, area and complexity.
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Unlu, Mehmet. "An Adjustable Impedance Matching Network Using Rf Mems Technology." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/1124676/index.pdf.
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This thesis presents design, modeling, and fabrication of an RF MEMS
adjustable impedance matching network. The device employs the basic triple stub
matching technique for impedance matching. It has three adjustable length stubs
which are implemented using capacitively loaded coplanar waveguides. The
capacitive loading of the stubs are realized using the MEMS switches which are
evenly distributed over the stubs. There are 40 MEMS bridges on each stub whichare separated with λ
/40 spacing making a total of 120 MEMS switches in the structure. The variability of the stub length is accomplished by closing the MEMS switch nearest to the required stub length, and making a virtual short circuit to ground. The device is theoretically capable of doing matching to every point on the Smith chart. The device is built on coplanar waveguide transmission lines. It has a center operating frequency of 10GHz, but because of its adjustability property it is expected to work in 1-40GHz range. It has dimensions of 8950 ×
5720µ
m2. This work is the continuation of the first national work on fabrication of RF MEMS devices. The device in this work is fabricated using the surface micromachining technology in the microelectronic facilities of Middle East Technical University.
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Thompson, Mark. "Controlling the Pi impedance matching network for fast antenna tuning." Thesis, University of York, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245897.
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Oliviera, Elder Eldervitch Carneiro de. "Antenas de microfita com patch quase-fractal para aplica??es em Redes WPAN/WLAN." Universidade Federal do Rio Grande do Norte, 2008. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15213.
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The microstrip antennas are in constant evidence in current researches due to several advantages that it presents. Fractal geometry coupled with good performance and convenience of the planar structures are an excellent combination for design and analysis of structures with ever smaller features and multi-resonant and broadband. This geometry has been applied in such patch microstrip antennas to reduce its size and highlight its multi-band behavior. Compared with the conventional microstrip antennas, the quasifractal patch antennas have lower frequencies of resonance, enabling the manufacture of more compact antennas. The aim of this work is the design of quasi-fractal patch antennas through the use of Koch and Minkowski fractal curves applied to radiating and nonradiating antenna s edges of conventional rectangular patch fed by microstrip inset-fed line, initially designed for the frequency of 2.45 GHz. The inset-fed technique is investigated for the impedance matching of fractal antennas, which are fed through lines of microstrip. The efficiency of this technique is investigated experimentally and compared with simulations carried out by commercial software Ansoft Designer used for precise analysis of the electromagnetic behavior of antennas by the method of moments and the neural model proposed. In this dissertation a study of literature on theory of microstrip antennas is done, the same study is performed on the fractal geometry, giving more emphasis to its various forms, techniques for generation of fractals and its applicability. This work also presents a study on artificial neural networks, showing the types/architecture of networks used and their characteristics as well as the training algorithms that were used for their implementation. The equations of settings of the parameters for networks used in this study were derived from the gradient method. It will also be carried out research with emphasis on miniaturization of the proposed new structures, showing how an antenna designed with contours fractals is capable of a miniaturized antenna conventional rectangular patch. The study also consists of a modeling through artificial neural networks of the various parameters of the electromagnetic near-fractal antennas. The presented results demonstrate the excellent capacity of modeling techniques for neural microstrip antennas and all algorithms used in this work in achieving the proposed models were implemented in commercial software simulation of Matlab 7. In order to validate the results, several prototypes of antennas were built, measured on a vector network analyzer and simulated in software for comparison
As antenas de microfita est?o em constante evid?ncia nas pesquisas atuais, isso devido ?s in?meras vantagens que apresentam. A geometria fractal aliada ao bom desempenho e comodidade das estruturas planares s?o uma excelente combina??o para projetos e an?lise de estruturas cada vez menores e com caracter?sticas multi-ressonantes e banda larga. Essa geometria tem sido aplicada em antenas tipo patch em microfita para reduzir o seu tamanho e evidenciar o seu comportamento multi-banda. Em compara??o com as antenas em microfita convencionais, as antenas patch quase-fractais apresentam freq??ncias de resson?ncia inferiores, possibilitando a fabrica??o de antenas ainda mais compactas. O objetivo desse trabalho consiste no projeto de antenas patches quase-fractal por meio da utiliza??o de curvas fractais de Koch e Minkowski aplicado ?s margens radiante e n?o-radiante de uma antena inset-fed patch retangular convencional alimentada por linha de microfita com reentr?ncias, inicialmente projetada para a freq??ncia de 2,45 GHz a ser observada. A t?cnica inset-fed ? investigada para o casamento de imped?ncias das antenas fractais, que s?o alimentadas atrav?s de linhas de microfita com reentr?ncias. A efici?ncia dessa t?cnica ? investigada experimentalmente e comparada com simula??es realizadas pelo software comercial Ansoft Designer, usado para a an?lise precisa do comportamento eletromagn?tico das antenas atrav?s do m?todo dos momentos e pelo modelo neural proposto. Nessa disserta??o um estudo bibliogr?fico em teoria de antenas de microfita ? realizado, o mesmo estudo ? realizado a respeito da geometria fractal, dando ?nfase a suas mais diversas formas, t?cnicas de gera??o desses fractais bem como sua aplicabilidade. Este trabalho ainda apresenta um estudo em redes neurais artificiais, evidenciando os tipos/arquitetura de redes utilizadas e suas caracter?sticas, bem como os algoritmos de treinamento que foram utilizados para sua implementa??o. As equa??es dos ajustes dos par?metros para as redes utilizadas nesse trabalho foram deduzidas a partir do m?todo do gradiente. Tamb?m ser? realizada uma investiga??o com ?nfase na miniaturiza??o dessas novas estruturas propostas, indicando o quanto uma antena projetada com contornos fractais ? capaz de miniaturizar uma antena patch retangular convencional. O estudo tamb?m consiste de uma modelagem por meio de redes neurais artificiais dos mais diversos par?metros eletromagn?ticos das antenas quase-fractais. Os resultados apresentados demonstram a excelente capacidade das t?cnicas neurais para modelagem de antenas de microfita, e todos os algoritmos utilizados nesse trabalho na obten??o dos modelos propostos foram implementados no software comercial de simula??o Matlab 7. Com a finalidade de validar os resultados obtidos, v?rios prot?tipos de antenas foram constru?dos, medidos em um analisador de rede vetorial e simulados em software para compara??o
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Smith, Nathanael J. "Novel Closed-Loop Matching Network Topology for Reconfigurable Antenna Applications." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1387733249.
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Alibakhshikenari, M., B. S. Virdee, P. Shukla, Y. Wang, L. Azpilicueta, M. Naser-Moghadasi, Chan H. See, et al. "Impedance Bandwidth Improvement of a Planar Antenna Based on Metamaterial-Inspired T-Matching Network." IEEE, 2021. http://hdl.handle.net/10454/18486.
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yesIn this paper a metamaterial-inspired T-matching network is directly imbedded inside the feedline of a microstrip antenna to realize optimum power transfer between the front-end of an RF wireless transceiver and the antenna. The proposed T-matching network, which is composed of an arrangement of series capacitor, shunt inductor, series capacitor, exhibits left-handed metamaterial characteristics. The matching network is first theoretically modelled to gain insight of its limitations. It was then implemented directly in the 50-Ω feedline to a standard circular patch antenna, which is an unconventional methodology. The antenna’s performance was verified through measurements. With the proposed technique there is 2.7 dBi improvement in the antenna’s radiation gain and 12% increase in the efficiency at the center frequency, and this is achieved over a significantly wider frequency range by a factor of approximately twenty. Moreover, there is good correlation between the theoretical model, method of moments simulation, and the measurement results.
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Gadhavi, Divyaraj, and Trushar Pansuriya. "2.45 GHz Antenna Designs with Impedance Matching Network : NIBE AB, Markaryd, Sweden." Thesis, Högskolan i Halmstad, Akademin för informationsteknologi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-37758.
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This master thesis is a part of digitization project at NIBE AB, Markaryd, Sweden.Nowadays, the demand for digitization is increasing. One of the main goals ofdigitization is to build smart houses and industries to offer better lifestyles.NIBE is a company which produces heat pumps, water heaters, district waterheaters, digital stoves and etc. NIBE AB is planning to launch their new products witha communication module which helps users to control NIBE AB’s products remotelythrough their personal devices such as mobile phones, remote control devices and etc.The main objective of this thesis project is to improve these communicationmodules by improving their antenna with better design or replacing them with otherkinds of antennas for efficient communication and also accordingly design impedancematching networks for the system.This work presents the integrated results of an antenna for NIBE AB, tuned tocover 2.45 GHz ISM band which will implemented on a communication module. Wedesigned and simulated four types of different Printed Circuit Board (PCB) antennasand we got the better simulation results of Gain, Reflection Coefficient, VSWR andBand Width from these designs.Also, we used different types of substrates in the simulation to get goodresults and design the impedance matching networks accordingly. If we compare theresults with the current monopole antenna and its parameters, we have goodcharacteristic results in most of the aspects.
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Ronaghzadeh, Amin. "Improving The Efficiency Of Microwave Power Amplifiers Without Linearity Degradation Using Load And Bias Tuning In A New Configuration." Phd thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615730/index.pdf.
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Advanced digital modulation schemes used in the wireless applications, result in the modulated RF signals with high peak to average power ratio which requires linear amplification. On the other hand, the demand for a longer talk time with less battery volume and weight, especially in hand-held radio units, necessitate more power efficient methods to be utilized in power amplifier design. But improved linearity and efficiency have always been contradicting requirements demanding innovative power amplifier and linearizer design techniques.
Dynamically varying the load impedance and bias point of a transistor according to the varying envelope of the incoming RF signal also known as Dynamic Load Modulation (DLM) and Dynamic Supply Modulation (DSM), respectively, are two separate methods for improving the efficiency in power amplifier
design. In this dissertation, a combination of both variable gate bias and tunable load concepts is applied in an amplifier structure consisting of two transistors in parallel.
A novel computer aided design methodology is proposed for careful selection of the load and biasing points of the individual transistors. The method which is based on load-pull analysis performs sweeps on the gate bias voltages of the active devices and input drive level of the amplifier in order to obtain ranges of biases that result in the generation of IMD sweet spots. Following that, the amplifier is designed employing the load line theory and bias switching at the same time in order to enhance the efficiency in reduced drive levels while extending the output 1 dB compression point to higher values at higher drives.
Tunable matching networks are implemented utilizing varactor stacks in a &Picon
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Samuelsson, Peter. "Management of technology in the process industries: Matching market and machine." Doctoral thesis, KTH, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-199705.
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The process industries span multiple industrial sectors and constitute a substantial part of the entire manufacturing industry. Since companies belonging to this family of industries are often very asset intensive, their ability to respond to changes is often limited in the short term. The adaptation of the capabilities of existing processes, and conversely finding products and market segments to match the production system capabilities, are an important part of product- and market development activities in the process industry. The importance to companies in the process industry of having a well-articulated manufacturing strategy congruent with the business strategy is second to none. However, to facilitate manufacturing strategy developments, it is essential to start with an improved characterization and understanding of the material transformation system. To that end an extensive set of variables was developed and related measures and scales were defined. The resulting configuration model, focusing on company generic process capabilities in the process industries, is to be regarded as a conceptual taxonomy and as a proposition available for further testing. The usability of the model was subsequently assessed using “mini-cases” in the forestry industry, where the respondents confirmed that the company’s overall strategy could benefit from this kind of platform as a possible avenue to follow. The model was deployed as an instrument in the profiling of company material transformation systems to facilitate the further development of companies' functional and business strategies. The use of company-generic production capabilities was studied in three case companies representing the mineral, food and steel industries. The model was found by the respondents to be usable as a knowledge platform to develop production strategies. In the final analysis of the research results, a new concept emerged called “production capability configuration": A process-industrial company’s alignment of its generic production capabilities in the areas of raw materials, process technology and products to improve the consistency among the variable elements that define operations and improve the congruence between operations and its environment. From the perspective of value creation and capture, firms must be able to manufacture products in a competitive cost structure within the framework of a proper business model. By using the configuration model, the relationship between manufacturing and innovation activities has been studied in the previously mentioned three case studies. In many cases the gap in capability appears as a limitation in the production system, requiring development efforts and sometimes investments to overcome. This is illustrated with two examples from the steel industry, where development efforts of the production system capabilities are initiated to better match the market demands. One example is the increase the volume- and product flexibility of an existing stainless steel melt shop, resulting in a proposed oblong Argon Oxygen Decarburisation (AOD) converter configuration that was subsequently verified using water modelling. The second example is from a carbon steel mill, where the target was to increase the raw material- and volume flexibility of another melt shop, by modifying the capabilities of the Electric Arc Furnace (EAF). Enabling EAF technologies are further described and evaluated using operational data and engineering type of estimates.QC 20170116
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Wang, Jinhua. "A Wide Input Power Line Energy Harvesting Circuit For Wireless Sensor Nodes." Thesis, Virginia Tech, 2021. http://hdl.handle.net/10919/103426.
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Massive deployment of wireless IoT (Internet of Things) devices makes replacement or recharge of batteries expensive and impractical for some applications. Energy harvesting is a promising solution, and various designs are proposed to harvest power from ambient resources including thermal, vibrational, solar, wind, and RF sources. Among these ambient resources, AC powerlines are a stable energy source in an urban environment. Many researchers investigated methods to exploit this stable source of energy to power wireless IoT devices.
The proposed circuit aims to harvest energy from AC powerlines with a wide input range of from 10 to 50 A. The proposed system includes a wake-up circuit and is capable of cold-start. A buck-boost converter operating in DCM is adopted for impedance matching, where the impedance is rather independent of the operation conditions. So, the proposed system can be applied to various types of wireless sensor nodes with different internal impedances. Experimental results show that the proposed system achieves an efficiency of 80.99% under the powerline current of 50 A.M.S.
Nowadays, with the magnificent growth of IoT devices, a reliable, and efficient energy supply system becomes more and more important, because, for some applications, battery replacement is very expensive and sometimes even impossible. At this time, a well-designed self-contained energy harvesting system is a good solution. The energy harvesting system can extend the service life of the IoT devices and reduce the frequency of charging or checking the device. In this work, the proposed circuit aims to harvest energy from the AC power lines, and the harvested power intends to power wireless sensor nodes (WSNs). By utilizing the efficient and self-contained EH system, WSNs can be used to monitor the temperature, pressure, noise level and humidity etc. The proposed energy harvesting circuit was implemented with discrete components on a printed circuit board (PCB). Under a power line current of 50 A @ 50 Hz, the proposed energy harvesting circuit can harvest 156.6 mW, with a peak efficiency of 80.99 %.
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Refai, Wael Yahia. "A Linear RF Power Amplifier with High Efficiency for Wireless Handsets." Diss., Virginia Tech, 2014. http://hdl.handle.net/10919/25886.
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This research presents design techniques for a linear power amplifier with high efficiency in wireless handsets. The power amplifier operates with high efficiency at the saturated output power, maintains high linearity with enhanced efficiency at back-off power levels, and covers a broadband frequency response. The amplifier is thus able to operate in multiple modes (2G/2.5G/3G/4G). The design techniques provide contributions to current research in handset power amplifiers, especially to the converged power amplifier architecture, to reduce the number of power amplifiers within the handset while covering all standards and frequency bands around the globe.
Three main areas of interest in power amplifier design are investigated: high power efficiency; high linearity; and broadband frequency response. Multiple techniques for improving the efficiency are investigated with the focus on maintaining linear operation. The research applies a new technique to the handset industry, class-J, to improve the power efficiency while avoiding the practical issues that hinder the typical techniques (class-AB and class-F). Class-J has been implemented using GaN FET in high power applications. To our knowledge, this work provides the first implementation of class-J using GaAs HBT in a handset power amplifier.
The research investigates the linearity, and the nature and causes of nonlinearities. Multiple concepts for improving the linearity are presented, such as avoiding odd-degree harmonics, and linearizing the relationship between the output current and the input voltage of the amplifier at the fundamental frequency. The concept of bias depression in HBT transistors is introduced with a bias circuit that reduces the bias-offset effect to improve linearity at high output power.
A design methodology is presented for broadband matching networks, including the component loss. The methodology offers a quick and accurate estimation of component values, giving more degrees of freedom to meet the design specifications. It enables a trade-off among high out-of-band attenuation, number/size of components, and power loss within the network.
Although the main focus is handset power amplifiers, most of the developed techniques can be applied to a wide range of power amplifiers.Ph. D.
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Procházka, Michal. "NQR spektroskopie - návrh metod měření." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2013. http://www.nusl.cz/ntk/nusl-219990.
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Nuclear quadropole spectroscopy is a modern analytical method for detecting specific solid state materials, e.g. explosives, drugs etc. It uses phenomenon of atomic nucleus called nuclear quadrupole moment. NQR method is very similar to common nuclear magnetic resonance (NMR) that is why major principles are explained using NMR. The thesis deals with basic principle of NQR, its usage for explosives detection and also detection of other chemical compounds and many other useful applications. The thesis deals with specific circuit design, techniques for sufficient sensitivity, impedance matching and circuit isolation. Practical part consists of simulations as well as designs of a few impedance transformers, pi-networks, and coils. Also experimental probe was created. In the last part, NQR workplace was assembled and a few chemical compounds were detected. These were KClO3, NaClO3 and NaNO2 . Finally minimum detectable amount of potassium chlorate as the strongest signal of these was determined.
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Nicolas, Dominique. "Conception de circuits RF en CMOS SOI pour modules d'antenne reconfigurables." Thesis, Toulouse 3, 2017. http://www.theses.fr/2017TOU30088/document.
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Dans le contexte des applications mobiles, les contraintes de conception des chaînes d'émission toujours plus performantes et de taille réduite demandent de compenser la forte sensibilité des caractéristiques des antennes à leur environnement. En particulier, il est nécessaire de maîtriser l'impédance de l'antenne pour optimiser l'efficacité énergétique de la chaîne de transmission. Or, les solutions actuelles se montrent encombrantes. Dans cette thèse, plusieurs pistes basées sur l'implémentation de condensateurs variables ont été étudiées et ont conduit à la réalisation et la caractérisation de nouveaux dispositifs RF intégrés à même de participer à cet effort. Après une présentation du contexte et de l'état de l'art, nous proposons une étude de condensateurs variables basés sur la technique des capacités commutées. L'étude a permis la réalisation de deux condensateurs variables en technologie CMOS SOI 130 nm pour des applications d'adaptation d'impédance et d'antenne agile en fréquence. Un premier démonstrateur d'antenne fente agile en fréquence visant les bandes LTE situées entre 500 MHz et 1 GHz et utilisant ce type de condensateur a ensuite été réalisé puis validé. Un système d'accord permettant de corriger les désadaptations d'antenne a ensuite été étudié et a donné lieu à la réalisation de deux circuits intégrés en technologie CMOS SOI 130 nm. Le premier circuit est un détecteur d'impédance capable de fonctionner sur une gamme de puissance étendue de 0-40 dBm pour une plage de fréquences de 600 MHz-2,4 GHz. Le deuxième circuit intègre une version améliorée du détecteur avec un circuit d'adaptation variable autorisant la réalisation d'un système d'accord d'antenne autonome et compact représentant une avancée importante par rapport à l'état de l'artIn the context of mobile applications, design constraints on always more performant and size-constrained emitting front-ends ask to compensate for strong sensitiveness of antennas characteristics to their environment. In particular, it is necessary to control the antenna impedance in order to optimize the energy efficiency of the transmitting front-end. Yet, current solutions are bulky. I this thesis, several ways based on the implementation of variable capacitors have been studied and have led to the design and characterization of new integrated RF devices that can participate to this effort. After a presentation of the context and the state-of-the-art, we propose a study of switched-capacitor-based variable capacitors. This study allowed the design of two variable capacitors in 130 nm CMOS SOI technology for impedance matching and frequency-agile antenna applications. Then, a first demonstrator module of a frequency-agile antenna aiming for 500 MHz-1 GHz LTE bands and using this type of capacitor has been designed and validated. A tunable system allowing the correction of antenna mismatch has then been studied and has led to the design of two 130 nm CMOS SOI integrated circuits. The first circuit is an impedance detector that is able to work on a 0-40 dBm power range and a 600 MHz-2.5 GHz frequency range. The second integrated circuit includes an improved version of the detector with a tunable matching network which both allow the fabrication of an autonomous, compact antenna tunable system showing significant progress relative to the state-of-the-art
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Giuliano, Alessandro. "Enhanced piezoelectric energy harvesting powered wireless sensor nodes using passive interfaces and power management approach." Thesis, Cranfield University, 2014. http://dspace.lib.cranfield.ac.uk/handle/1826/8834.
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Low-frequency vibrations typically occur in many practical structures and systems when in use, for example, in aerospaces and industrial machines. Piezoelectric materials feature compactness, lightweight, high integration potential, and permit to transduce mechanical energy from vibrations into electrical energy. Because of their properties, piezoelectric materials have been receiving growing interest during the last decades as potential vibration- harvested energy generators for the proliferating number of embeddable wireless sensor systems in applications such as structural health monitoring (SHM). The basic idea behind piezoelectric energy harvesting (PEH) powered architectures, or energy harvesting (EH) more in general, is to develop truly “fit and forget” solutions that allow reducing physical installations and burdens to maintenance over battery-powered systems. However, due to the low mechanical energy available under low-frequency conditions and the relatively high power consumption of wireless sensor nodes, PEH from low-frequency vibrations is a challenge that needs to be addressed for the majority of the practical cases. Simply saying, the energy harvested from low-frequency vibrations is not high enough to power wireless sensor nodes or the power consumption of the wireless sensor nodes is higher than the harvested energy. This represents a main barrier to the widespread use of PEH technology at the current state of the development, despite the advantages it may offer. The main contribution of this research work concerns the proposal of a novel EH circuitry, which is based on a whole-system approach, in order to develop enhanced PEH powered wireless sensor nodes, hence to compensate the existing mismatch between harvested and demanded energy. By whole-system approach, it is meant that this work develops an integrated system-of-systems rather than a single EH unit, thus getting closer to the industrial need of a ready- to-use energy-autonomous solution for wireless sensor applications such as SHM. To achieve so, this work introduces: Novel passive interfaces in connection with the piezoelectric harvester that permit to extract more energy from it (i.e., a complex conjugate impedance matching (CCIM) interface, which uses a PC permalloy toroidal coil to achieve a large inductive reactance with a centimetre- scaled size at low frequency; and interfaces for resonant PEH applications, which exploit the harvester‟s displacement to achieve a mechanical amplification of the input force, a magnetic and a mechanical activation of a synchronised switching harvesting on inductor (SSHI) mechanism). A novel power management approach, which permits to minimise the power consumption for conditioning the transduced signal and optimises the flow of the harvested energy towards a custom-developed wireless sensor communication node (WSCN) through a dedicated energy-aware interface (EAI); where the EAI is based on a voltage sensing device across a capacitive energy storage. Theoretical and experimental analyses of the developed systems are carried in connection with resistive loads and the WSCN under excitations of low frequency and strain/acceleration levels typical of two potential energy- autonomous applications, that are: 1) wireless condition monitoring of commercial aircraft wings through non-resonant PEH based on Macro-Fibre Composite (MFC) material bonded to aluminium and composite substrates; and wireless condition monitoring of large industrial machinery through resonant PEH based on a cantilever structure. shown that under similar testing conditions the developed systems feature a performance in comparison with other architectures reported in the literature or currently available on the market. Power levels up to 12.16 mW and 116.6 µW were respectively measured across an optimal resistive load of 66 277 kΩ for an implemented non-resonant MFC energy harvester on aluminium substrate and a resonant cantilever-based structure when no interfaces were added into the circuits. When the WSCN was connected to the harvesters in place of the resistive loads, data transmissions as fast as 0.4 and s were also respectively measured. By use of the implemented passive interfaces, a maximum power enhancement of around 95% and 452% was achieved in the two tested cases and faster data transmissions obtained with a maximum percentage improvement around 36% and 73%, respectively. By the use of the EAI in connection with the WSCN, results have also shown that the overall system‟s power consumption is as low as a few microwatts during non- active modes of operation (i.e., before the WSCN starts data acquisition and transmission to a base station). Through the introduction of the developed interfaces, this research work takes a whole-system approach and brings about the capability to continuously power wireless sensor nodes entirely from vibration-harvested energy in time intervals of a few seconds or fractions of a second once they have been firstly activated. Therefore, such an approach has potential to be used for real-world energy- autonomous applications of SHM.
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Freitas, Vitor. "Etude et réalisation de réseaux d'adaptation d'impédances accordables linéaires et non linéaires, sur PCB et silicium CMOS, pour des applications en radiofréquences." Thesis, Grenoble, 2012. http://www.theses.fr/2012GRENT059/document.
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L’objectif de ce travail est d’aborder la conception de réseaux d’adaptation d’impédance accordable (RAA) dans deux contextes bien distincts en radiofréquences : le RAA en faible signal et le RAA en fort signal.Concernant les aspects faible signal, des critères de performance de RAA ont été établis et étudiés. Une nouvelle expression générale de l’efficacité d’un RAA a été développée. Elle permet de prédire le rendement d’un RAA à partir des facteurs de qualité des composants dont on dispose dans une technologie donnée et du rapport de transformation à réaliser. Des abaques de couverture d’impédances en fonction des pertes d’insertion ont été calculés. Ils mettent en évidence les régions de couverture où le RAA apporte une amélioration à la performance du système, pour diverses topologies de RAA.Un démonstrateur sur PCB a été réalisé. Il est constitué de deux RAA, qui assurent l’adaptation simultanée d’un amplificateur de puissance sur une large plage d’impédances, comprises dans un cercle de l’abaque de Smith d’équation VSWR < 5 :1. La zone de couverture a été mesurée et présentée en fonction des pertes d’insertion, qui mettent en évidence les régions où les RAA contribuent à l’amélioration de la performance de l’amplificateur et celles où les pertes d’insertion du RAA n’arrivent pas à compenser le gain du à la réduction des coefficients de réflexion.Dans une seconde partie, la conception de RAA en fort signal a été traitée. L’objectif a été de présenter à la sortie d’un amplificateur de puissance les impédances qui optimisent son efficacité pour chaque puissance de travail. Un démonstrateur en technologie CMOS SOI 130 nm a été conçu et simulé. Il consiste en un amplificateur de puissance pour le standard WCDMA, fonctionnant à 900 MHz, et un RA accordable par des varactors MOS, capable de générer les impédances optimales correspondant à des puissances de sortie comprises entre 20 et 30 dBm. Les résultats ont mis en évidence le bénéfice apporté par l’insertion d’un RA accordable par rapport à un RA fixeThe aim of this research was the design of tunable matching networks, in two different contexts: the TMN at low and high signals.Performance criteria of TMN were studied. A general expression has been developed that estimates the TMN efficiency in function of the quality factor of the components used. The impedance coverage of different RAA topologies was plotted in function of the insertion losses.For the small signal, we designed a prototype in PCB, composed by two TMN, which ensure the simultaneous matching of a power amplifier in a wide range of impedances, included in a circle of the Smith chart VSWR < 5: 1. The coverage area was measured and presented in function of the insertion losses, emphasizing the areas where the TMN contribute to improve the amplifier performance and those where insertion losses of the TMN are not able to compensate gain with the reduction of the reflection coefficients.Subsequently, we discussed the design of TMN for the large signal. The objective is to present at the output of a power amplifier, the impedances that optimize efficiency for each power of operation. A 130 nm SOI prototype was designed and simulated, consisting of a power amplifier for WCDMA standard, 900 MHz, and a MN tunable by MOS varactors able to produce the optimal impedances corresponding to an output power between 20 and 30 dBm. The results showed the benefit provided by inserting a tunable MN compared to a fixed one
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Panunzio, Paulo Armando [UNESP]. "Proposta de equipamento de conexão à rede para a utilização da geração de energia solar em consumidores de pequeno e médio porte." Universidade Estadual Paulista (UNESP), 2016. http://hdl.handle.net/11449/136277.
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A proposta dessa Tese é o projeto e desenvolvimento de um sistema de fornecimento de energia elétrica conectada à rede sem a utilização de circuitos eletrônicos complexos. O sistema eletroeletrônico convencional utiliza um inversor de frequência que transfere a potência ativa do nível de tensão e corrente CC para o nível compatível com a rede elétrica CA em frequência, tensão e sincronismo de fases. Já o desenvolvimento do projeto teve como parte experimental a utilização de indutores adequados com valores variáveis de 200 mH a 500 mH entre os painéis fotovoltaicos e a rede convencional. A tensão e a corrente máxima de CC foi de 29,6 V e a máxima possível foi de 20 amperes. Utilizou-se do princípio do casamento de impedâncias entre o painel fotovoltaico e o sistema de fornecimento de energia CA. Assim o painel fotovoltaico fornece somente potência ativa para a rede não interferindo no sincronismo. Na onda de tensão e corrente CA há uma pequena alteração no nível CA em relação a simetria do eixo dos tempos, dentro dos limites previstos para a rede convencional de energia. Logo evidencia-se o fornecimento de potência ativa para a rede CA. Os resultados obtidos permitiram inserção na rede de cerca de 10% da potência ativa dos painéis fotovoltaicos, com a otimização dos valores dos indutores, ocorrendo a transferência de potência ativa dos painéis fotovoltaicos para a rede convencional de energia CA.
The purpose of this thesis is the design and development of a delivery system of electricity connected to the network without the use of complex electronic circuits. The electronics system uses a frequency inverter that transfers the active power level voltage and DC current to the level compatible with the mains AC frequency, voltage and phase synchronization. But the project was to develop experimental part the use of suitable inductors with variable values of 200 mH to 500 mH between the PV panels and the conventional network. The maximum current was 20 amperes. We used the principle of impedance matching between the photovoltaic panel and the power supply system CA. So the photovoltaic panel supplies only active power to the grid not interfering with the timing. In the wave of AC voltage and current for a small change in CA level against the symmetry axis of time. Logo is evident in the supply of active power to the grid CA. The results allowed inclusion in the network of about 10% of the active power of photovoltaic panels by optimizing the values of the inductors for the occurrence of power transfer of conventional photovoltaic panels for energy occurs CA.
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Chan, wai po Francis. "Conception d’une tête radiofréquence auto adaptative au milieu de propagation pour les applications médicales." Thesis, Bordeaux 1, 2010. http://www.theses.fr/2010BOR14052/document.
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L'impédance d'entrée d'une antenne miniature est fortement affectée par des facteurs environnementaux à l'origine de pertes de puissance réduisant l'efficacité énergétique des têtes radiofréquences dans les applications RF, en particulier dans la télémétrie des implants cardiaques. Le but de mes études est de développer une unité de calibration d'impédance d'antenne très faible consommation capable d'adapter toute variation de l'impédance d'entrée de l'antenne à l'impédance de la source radiofréquence. La première partie de mon étude est axée sur la conception au niveau système d'une approche nouvelle de calibration automatique du système. Un réseau d'adaptation automatique d'impédance sans coupleur et fonctionnant de façon directe est étudié et permet d'optimiser la taille du dispositif, la vitesse de l'adaptation, la consommation d'énergie et les performances globales. Deuxièmement, une nouvelle méthode de synthèse du réseau d'adaptation variable est proposée pour réduire fortement la complexité globale de l'algorithme d'adaptation. La troisième partie de mon étude est axée sur la fabrication d'un démonstrateur hybride fonctionnant dans la bande médicale MICS afin de valider le concept auto adaptatif d'impédance. Un banc expérimental qui comprend une antenne immergée dans son milieu connectée au démonstrateur piloté par un microcontrôleur a été mis en place et a permis d'atteindre un coefficient de réflexion jusqu'à -30dB avec un temps de calibration inférieur à 1ms. La dernière partie de mon travail consiste à concevoir le circuit d'adaptation automatique d'impédance d'antenne très faible consommation fonctionnant dans la bande ISM 2.4GHz en utilisant la technologie CMOS 0.13umAntenna input impedance is highly affected by environmental factors increasing the losses or reducing the power efficiency of the radiofrequency transceiver in many RF applications such as in implantable pacemaker device telemetry. The purpose of my study is to develop a low power fully integrated antenna-impedance tuning unit to match any variation of the antenna impedance to the source. The first part of my study is focused on the system-level design of a new approach to automatically match the system. A couplerless single step automatic matching network is investigated to optimize the die size, the speed, the power consumption and the overall performance. Second, a new method for synthesizing an automatic matching network is developed reducing strongly the overall complexity of the matching algorithm. The third part of my study is focused on the fabrication of a hybrid demonstrator operating at the Medical Implantable Communication Service (MICS) frequency band to validate the concept. An experimental set-up including the antenna tuning unit, a microcontroller and a pacemaker antenna connected to the demonstrator was done achieving a reflection coefficient up to -30dB, an overall tuning time less than 1ms. The last part of my work is to design the entire automatic matching network circuit in 0.13um CMOS technology including a front-end transceiver designed under ultra low power constraints and operating at 2.4GHz ISM frequency band. The additional items overall power consumption is less than 1.5mW under 1.2V supply voltage
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Chan, Wai Po Françis. "Conception d'une tête radiofréquence auto adaptative au milieu de propagation pour les applications médicales." Phd thesis, Université Sciences et Technologies - Bordeaux I, 2010. http://tel.archives-ouvertes.fr/tel-00585651.
Full textAbstract:
L'impédance d'entrée d'une antenne miniature est fortement affectée par des facteurs environnementaux à l'origine de pertes de puissance réduisant l'efficacité énergétique des têtes radiofréquences dans les applications RF, en particulier dans la télémétrie des implants cardiaques. Le but de mes études est de développer une unité de calibration d'impédance d'antenne très faible consommation capable d'adapter toute variation de l'impédance d'entrée de l'antenne à l'impédance de la source radiofréquence. La première partie de mon étude est axée sur la conception au niveau système d'une approche nouvelle de calibration automatique du système. Un réseau d'adaptation automatique d'impédance sans coupleur et fonctionnant de façon directe est étudié et permet d'optimiser la taille du dispositif, la vitesse de l'adaptation, la consommation d'énergie et les performances globales. Deuxièmement, une nouvelle méthode de synthèse du réseau d'adaptation variable est proposée pour réduire fortement la complexité globale de l'algorithme d'adaptation. La troisième partie de mon étude est axée sur la fabrication d'un démonstrateur hybride fonctionnant dans la bande médicale MICS afin de valider le concept auto adaptatif d'impédance. Un banc expérimental qui comprend une antenne immergée dans son milieu connectée au démonstrateur piloté par un microcontrôleur a été mis en place et a permis d'atteindre un coefficient de réflexion jusqu'à -30dB avec un temps de calibration inférieur à 1ms. La dernière partie de mon travail consiste à concevoir le circuit d'adaptation automatique d'impédance d'antenne très faible consommation fonctionnant dans la bande ISM 2.4GHz en utilisant la technologie CMOS 0.13um. Antenna input impedance is highly affected by environmental factors increasing the losses or reducing the power efficiency of the radiofrequency transceiver in many RF applications such as in implantable pacemaker device telemetry. The purpose of my study is to develop a low power fully integrated antenna-impedance tuning unit to match any variation of the antenna impedance to the source. The first part of my study is focused on the system-level design of a new approach to automatically match the system. A couplerless single step automatic matching network is investigated to optimize the die size, the speed, the power consumption and the overall performance. Second, a new method for synthesizing an automatic matching network is developed reducing strongly the overall complexity of the matching algorithm. The third part of my study is focused on the fabrication of a hybrid demonstrator operating at the Medical Implantable Communication Service (MICS) frequency band to validate the concept. An experimental set-up including the antenna tuning unit, a microcontroller and a pacemaker antenna connected to the demonstrator was done achieving a reflection coefficient up to -30dB, an overall tuning time less than 1ms. The last part of my work is to design the entire automatic matching network circuit in 0.13um CMOS technology including a front-end transceiver designed under ultra low power constraints and operating at 2.4GHz ISM frequency band. The additional items overall power consumption is less than 1.5mW under 1.2V supply voltage.
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Janse, van Rensburg Christo. "A SiGe BiCMOS LNA for mm-wave applications." Diss., University of Pretoria, 2012. http://hdl.handle.net/2263/26501.
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A 5 GHz continuous unlicensed bandwidth is available at millimeter-wave (mm-wave) frequencies around 60 GHz and offers the prospect for multi gigabit wireless applications. The inherent atmospheric attenuation at 60 GHz due to oxygen absorption makes the frequency range ideal for short distance communication networks. For these mm-wave wireless networks, the low noise amplifier (LNA) is a critical subsystem determining the receiver performance i.e., the noise figure (NF) and receiver sensitivity. It however proves challenging to realise high performance mm-wave LNAs in a silicon (Si) complementary metal-oxide semiconductor (CMOS) technology. The mm-wave passive devices, specifically on-chip inductors, experience high propagation loss due to the conductivity of the Si substrate at mm-wave frequencies, degrading the performance of the LNA and subsequently the performance of the receiver architecture. The research is aimed at realising a high performance mm-wave LNA in a Si BiCMOS technology. The focal points are firstly, the fundamental understanding of the various forms of losses passive inductors experience and the techniques to address these issues, and secondly, whether the performance of mm-wave passive inductors can be improved by means of geometry optimising. An associated hypothesis is formulated, where the research outcome results in a preferred passive inductor and formulates an optimised passive inductor for mm-wave applications. The performance of the mm-wave inductor is evaluated using the quality factor (Q-factor) as a figure of merit. An increased inductor Q-factor translates to improved LNA input and output matching performance and contributes to the lowering of the LNA NF. The passive inductors are designed and simulated in a 2.5D electromagnetic (EM) simulator. The electrical characteristics of the passive structures are exported to a SPICE netlist which is included in a circuit simulator to evaluate and investigate the LNA performance. Two LNAs are designed and prototyped using the 13μ-m SiGe BiCMOS process from IBM as part of the experimental process to validate the hypothesis. One LNA implements the preferred inductor structures as a benchmark, while the second LNA, identical to the first, replaces one inductor with the optimised inductor. Experimental verification allows complete characterization of the passive inductors and the performance of the LNAs to prove the hypothesis. According to the author's knowledge, the slow-wave coplanar waveguide (S-CPW) achieves a higher Q-factor than microstrip and coplanar waveguide (CPW) transmission lines at mm-wave frequencies implemented for the 130 nm SiGe BiCMOS technology node. In literature, specific S-CPW transmission line geometry parameters have previously been investigated, but this work optimises the signal-to-ground spacing of the S-CPW transmission lines without changing the characteristic impedance of the lines. Optimising the S-CPW transmission line for 60 GHz increases the Q-factor from 38 to 50 in simulation, a 32 % improvement, and from 8 to 10 in measurements. Furthermore, replacing only one inductor in the output matching network of the LNA with the higher Q-factor inductor, improves the input and output matching performance of the LNA, resulting in a 5 dB input and output reflection coefficient improvement. Although a 5 dB improvement in matching performance is obtained, the resultant noise and gain performance show no significant improvement. The single stage LNAs achieve a simulated gain and NF of 13 dB and 5.3 dB respectively, and dissipate 6 mW from the 1.5 V supply. The LNA focused to attain high gain and a low NF, trading off linearity and as a result obtained poor 1 dB compression of -21.7 dBm. The LNA results are not state of the art but are comparable to SiGe BiCMOS LNAs presented in literature, achieving similar gain, NF and power dissipation figures.Dissertation (MEng)--University of Pretoria, 2012.
Electrical, Electronic and Computer Engineering
unrestricted
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Fouladi, Azarnaminy Siamak. "Reconfigurable Impedance Matching Networks Based on RF-MEMS and CMOS-MEMS Technologies." Thesis, 2010. http://hdl.handle.net/10012/5171.
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Reconfigurable impedance matching networks are an integral part of multiband radio-frequency (RF) transceivers. They are used to compensate for the input/output impedance variations between the different blocks caused by switching the frequency band of operation or by adjusting the output power level. Various tuning techniques have been developed to construct tunable impedance matching networks employing solid-state p-i-n diodes and varactors. At millimeter-wave frequencies, the increased loss due to the low quality factor of the solid-state devices becomes an important issue. Another drawback of the solid-state tuning elements is the increased nonlinearity and noise at higher RF power levels.
The objective of the research described in this thesis is to investigate the feasibility of using RF microelectromechanical systems (RF-MEMS) technology to develop reconfigurable impedance matching networks. Different types of tunable impedance matching networks with improved impedance tuning range, power handling capability, and lower insertion loss have been developed. Another objective is to investigate the realization of a fully integrated one-chip solution by integrating MEMS devices in standard processes used for RF integrated circuits (RFICs).
A new CMOS-MEMS post-processing technique has been developed that allows the integration of tunable RF MEMS devices with vertical actuation within a CMOS chip. Various types of CMOS-MEMS components used as tuning elements in reconfigurable RF transceivers have been developed. These include tunable parallel-plate capacitors that outperform the available CMOS solid-state varactors in terms of quality factor and linearity. A tunable microwave band-pass filter has been demonstrated by employing the proposed RF MEMS tunable capacitors. For the first time, CMOS-MEMS capacitive type switches for microwave and millimeter-wave applications have been developed using TSMC 0.35-µm CMOS process employing the proposed CMOS-MEMS integration technique. The switch demonstrates an excellent RF performance from 10-20 GHz.
Novel MEMS-based reconfigurable impedance matching networks integrated in standard CMOS technologies are also presented. An 8-bit reconfigurable impedance matching network based on the distributed MEMS transmission line (DMTL) concept operating at 13-24 GHz is presented. The network is implemented using standard
0.35-µm CMOS technology and employs a novel suspended slow-wave structure on
a silicon substrate. To our knowledge, this is the first implementation of a DMTL tunable MEMS
impedance matching network using a standard CMOS technology. A reconfigurable
amplifier chip for WLAN applications operating at 5.2 GHz is also designed and implemented. The amplifier achieves maximum power gain under variable load and
source impedance conditions by using the integrated RF-MEMS impedance
matching networks. This is the first single-chip implementation of
a reconfigurable amplifier using high-Q MEMS impedance matching networks.
The monolithic CMOS implementation of the proposed RF MEMS impedance matching networks enables the development of future low-cost single-chip RF multiband transceivers with improved performance and functionality.
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Du, Plessis W. P. (Warren Paul). "A genetic algorithm for impedance matching network design." Diss., 2003. http://hdl.handle.net/2263/27111.
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Please read the abstract (Summary) in the section 00front of this documentDissertation (MEng (Electronic Engineering))--University of Pretoria, 2007.
Electrical, Electronic and Computer Engineering
MEng
Unrestricted
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HE, JIAN-XUN, and 何建勳. "Design of broadband impedance matching network and amplifier." Thesis, 1987. http://ndltd.ncl.edu.tw/handle/72254748977017305159.
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Hsu, Sen-Kuei, and 許森貴. "Adaptive Impedance Matching Network for Radio Frequency Identification Tag." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/17140397573674864390.
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chiu, Wen-Chih, and 邱文志. "The modeling and controller design of radio frequency impedance matching network in PECVD equipment." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/15721033415570589536.
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碩士國立交通大學
機械工程系所
94
In semiconductor processing, the Radio Frequency (RF) power source is used to create plasma for wafer fabrication. Power transmission plays a very important role in wafer processing. Unstable power transmission will lead to unstable plasma, and wafer processing can not achieve it's goal. The impedance matching network behaves like a bridge for power transmission. It reduces the reflective power from the chamber, and increases the transmission power into the chamber, and provides a stable operating power. In this thesis, we use an impedance matching network in a plasma enhanced chemical vapor deposition (PECVD) equipment. First, we use neural network approach to establish the impedance model of the matching network, and the result will be compared with the traditional method to explain its elegance in dealing with stray impedance. Next, we analyze the relationship of input/output signals of RF sensor board in the matching network, and create mathematical model accordingly. Finally, we apply Neuro-Sliding mode control theory to control impedance matching network, and compare its result with the existing controller. The performance of new controller design will be discussed, and the importance of RF sensor signal processing to the control of impedance matching network will be high lighted in the conclusion portion of this research.
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Su, Hong-Jhe, and 蘇宏哲. "Embedded DC Servo Electrical Control System Design and Its Application on the Impedance Matching Network." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/79474036590977005719.
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碩士國立勤益科技大學
電機工程系
97
DC servo control system plays an important role in the process of industrial production, such as impedance matching network, robotics, CNC engraving and milling machines, and sewing machines, etc. Using the DC servo motor to drive the mechanism, therefore machine tools achieve their manufacturing function. When DC servo motors drive the robot arm, the robot can execute complex operation; drive the sewing machine, sewing machine can embroider the desired patterns. In this thesis, we applied the embedded DC servo electrical control system to the impedance matching networks which have broad application on the semiconductor industry. By tuning the variable capacitors the impedance matching condition is obtained. In order to obtain more widely application, an embedded DC servo electrical control system is developed in this thesis, which used PIC microcontroller as the control kernel and integrated the necessary peripheral interface, such as including push buttons, LCD displayer and connectors. Connecting the necessary junction points to the connectors, it is easy applied to other DC servo system. This embedded DC servo electrical control system also reserved the communication port to benefit the control data transfer between PIC and PC. The communication programs are written using MPLAB and Labview respectively. In this thesis, our final objective is to control the matching network. Therefore, the developed embedded DC servo electrically control system is applied to the matching network. In plasma system, matching network is installed between RF generator and vacuum chamber. By tuning the variable capacitors which driving by DC servo motors, such as the two arms’ variable capacitors in π-type matching network, the maximum power transfer is obtained to guarantee the successful plasma generation. Therefore, many plasma processes can be implemented, such as dry etching, sputtering, plasma enhanced chemical vapor deposition, reactive ion etching, and high density plasma. In this thesis, the developed embedded DC servo electrical control system mainly contains a PIC CPU, two DC driver circuits, potentiometers, phase detection circuit and the necessary peripheral interface. Integrating the mechanical structure, the electrical control board, system identification and the basic control theorem, the servo control of π type matching network is implemented. The experimental results, including PID regulation and tracking control, communication interface between PIC and PC, demonstrate the feasibility of the built electrical control system for matching network.
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Chen, Jun-You, and 陳俊佑. "Design of Dipole Antenna, BALUN, and Impedance Matching Network for the cube satellite RF system." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/86qqm3.
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碩士國立中央大學
光機電工程研究所
105
A low-cost, high-efficiency dipole antenna module for cube satellite including radiator, BALUN, and impedance matching network design by using COTS (Commercial Off-The-Shelf) components is purposed. A delay-line type BALUN is designed for 1.8 watt RF signal input, and a L-type impedance matching network is designed with low-cost COTS passive component to improve the RF power transmission efficiency between transceiver and antenna module. The input impedance of antenna module is 50 ohm (±1%) and the S11 is lower than -30dB. This antenna module design has been successfully verified in two different experiments to provide 40 kilometers wireless transmission at UHF band for two cube satellites with the 1.8 watt transmit power and 14.15dBi gain Yagi antenna, the maximum distance of wireless transmission is estimated to 131 kilometers by using least square estimation with the same experimental condition.