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Dissertations / Theses on the topic 'Digital and analogic communication'
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Hickok, Tom. "Space Communication Channel Emulation Using Digital and Analog Signal Processing." DigitalCommons@CalPoly, 2010. https://digitalcommons.calpoly.edu/theses/398.
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New communication protocols intended for large distances, including low orbit and deep space, can be inherently difficult to evaluate since trial implementations are often impractical. In order to accurately measure the performance of a new protocol, it is important to evaluate it in an environment that most closely matchs that in which it will be used. This thesis demonstrates the ability to emulate a space communications channel through digitizing a transmission centered at an intermediate frequency of 70 MHz with a bandwidth of 24 MHz, digitally introducing the characteristics of a transmission through space, and reconstructing the digital data to its analog counterpart. Delay, Doppler shift, Gaussian noise, and fading are among the most prevalent characteristics of such a channel, and thus were the focus of this thesis. Special care was given to the design of each digital and analog component to maintain the integrity of the original signal by minimizing all undesired noise introduced. The final design can accurately produce a given dynamic transmission signature or continually output a static set of channel characteristic parameters to test new communication protocols.
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Modin, Larsson Lina, and Martina Jonsson. "Dagstidningskonsumtion och hållbarhet: Miljöpåverkan av att läsa dagstidningar analogt jämfört med digitalt : Newspaper consumption and sustainability: Environmental impact of reading analog vs digital newspapers." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-188639.
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Kommunikationsteknologin befinner sig idag i ett övergångsläge mellan digitala och analoga tekniker. Inte minst påverkar detta dagstidningsindustrin. Samhällets generella uppfattning är att digitala tidningar anses ha låg eller ingen miljöpåverkan i jämförelse med den analoga tidningen. Att minska miljöpåverkan rent generellt ligger i samhällets intresse, därför är kommunikationsteknologiska lösningar under ständig utvärdering vad gäller dess miljöpåverkan och hur denna kan effektiviseras. Syftet med den här undersökningen är därför att analysera olika målgrupper och deras tidningskonsumtion, för att sedan utvärdera den miljömässiga påverkan som den innebär. På så sätt kan vi diskutera huruvida analog eller digital konsumtion är ett miljömässigt bättre alternativ för de studerade målgrupperna. Genom en litteraturstudie kunde vi uthämta teori för att ge grund till uppbyggnad av fältstudie och för vidare analyser av resultaten. Teorin behandlade tidningars livscykler i relation till miljöpåverkan. Utifrån sex semistrukturerade intervjuer formade vi sex fiktiva personas som representerade sex skilda målgrupper, fokuserade kring deras dagstidningskonsumtion. Dessa personas figurerade i ett moget scenario där det var lika vanligt förekommande att läsa den digitala versionen av dagstidningen som den analoga versionen. I diskussionen kunde vi göra rekommendationer i valet av tidningsformat för respektive målgrupp. Dessa var baserade på våra preliminära beräkningar och diskussioner. Slutsatser vi kunde dra var att valet av tidningsformat utifrån det mest miljömässigt gynnsamma var primärt beroende av lästiden, antalet läsar per version, antalet läsare per upplaga, den digitala enhetens energiförbrukning och avfallshantering.Communications technology is currently in a transition phase between digital and analog technologies. Not least, this affects the newspaper industry. Society's general view is that digital magazines are considered to have low or no environmental impact in comparison with the analog newspaper. Reducing the environmental impact is in general interests of the society, therefore communications technology solutions lies under constant evaluation in terms of their environmental impact and how this can be streamlined. The purpose of this study is to analyze different target groups and their newspaper consumption, to then evaluate the environmental impact of it. Thus we can discuss whether analog or digital consumption is a more environmentally favourable option for the studied target groups. Through a literature study, we could retrieve theory to provide a scientific basis for the construction of the field study and further analysis of the results. The theory treated newspapers' life cycles in relation to environmental impact. Based on six semi-structured interviews we formed six fictitious personas representing six distinct target groups, focused on their daily newspapers consumption. These personas figured in a mature scenario where reading the digital and the analog version of the newspaper was equally common. In the discussion we were able to establish recommendations for each target group providing the most favourable newspaper version. These were based on our preliminary calculations and discussions.Conclusions we could draw was that the choice of newspaper version based on environmental benefaction was primarily dependent on reading time, the number of readers per version, the number of readers per edition, the digital unit's energy consumption and end-of-life treatment.
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Thandri, Bharath Kumar. "Design of RF/IF analog to digital converters for software radio communication receivers." Texas A&M University, 2003. http://hdl.handle.net/1969.1/5774.
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Software radio architecture can support multiple standards by performing analogto-
digital (A/D) conversion of the radio frequency (RF) signals and running
reconfigurable software programs on the backend digital signal processor (DSP). A
slight variation of this architecture is the software defined radio architecture in which the
A/D conversion is performed on intermediate frequency (IF) signals after a single down
conversion.
The first part of this research deals with the design and implementation of a
fourth order continuous time bandpass sigma-delta (CT BP) C based on LC filters
for direct RF digitization at 950 MHz with a clock frequency of 3.8 GHz. A new ADC
architecture is proposed which uses only non-return to zero feedback digital to analog
converter pulses to mitigate problems associated with clock jitter. The architecture also has full control over tuning of the coefficients of the noise transfer function for obtaining the best signal to noise ratio (SNR) performance. The operation of the architecture is examined in detail and extra design parameters are introduced to ensure robust operation of the ADC. Measurement results of the ADC, implemented in IBM 0.25 µm SiGe BiCMOS technology, show SNR of 63 dB and 59 dB in signal bandwidths of 200 kHz
and 1 MHz, respectively, around 950 MHz while consuming 75 mW of power from ±
1.25 V supply.
The second part of this research deals with the design of a fourth order CT BP ADC based on gm-C integrators with an automatic digital tuning scheme for IF
digitization at 125 MHz and a clock frequency of 500 MHz. A linearized CMOS OTA
architecture combines both cross coupling and source degeneration in order to obtain
good IM3 performance. A system level digital tuning scheme is proposed to tune the
ADC performance over process, voltage and temperature variations. The output bit
stream of the ADC is captured using an external DSP, where a software tuning algorithm
tunes the ADC parameters for best SNR performance. The IF ADC was designed in
TSMC 0.35 µm CMOS technology and it consumes 152 mW of power from ± 1.65 V
supply.
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Hayashi, Takayuki. "A 1 V floating-point analog-to-digital converter for portable communication devices." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0005/MQ45436.pdf.
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Svensson, Jesper. "Barn i den digitala världen." Thesis, Blekinge Tekniska Högskola, Institutionen för teknik och estetik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-14627.
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Detta kandidatarbete handlar om hur skolan arbetar med digitaliseringen och hur de använder de digitala verktyg som finns. Det kommer handla om de övergångar digitaliseringen innebär för skolan och vad som kan vara hinder för skolan att digitaliseras. Kandidatarbetet kommer också ta upp vikten av vuxnas närvaro för de barnen som använder internet och blivit upprörda/besvärade av något som det sätt på internet. Den gestaltande delen av kandidatarbetet kommer att handla om barn som ännu inte börjat skolan. Barnen kommer att hjälpa till för att skapa sig en egen design på en applikation som de sedan skulle vilja använda. Barns vetskap om hur tekniken används är begränsad på ett positivt sätt som gör att de kan öppna upp för nya sätt att se tekniken. Barnen är villiga att använda tekniken och det spelar ingen roll om det skulle vara på ett papper eller digitalt. De gillar allra bäst närheten till vuxna när de får interagera med det som är framför dem.This Bachelor Thesis is about how the school works with digitalization and how they use the digital tools that are available. It is about the transitions that digitalization faces that could prevent the school from becoming more digitized. The work will also address the importance of adult’s presence for the children's use of the internet and support them if they had a bad experienced on the internet. The output of the Bachelor Thesis will be about children who have not yet started school. The children will help to create their own design on an application that they would like to play with. Children's knowledge of how technology is used is limited in a positive way, that enables them to open up new ways to see the technology. Children are willing to use the technology and it doesn't matter if it is paper or digital. They enjoy the company of grownups when they interact with what's in front of them.
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Gustafsson, E. Martin I. "Reconfigurable Analog to Digital Converters for Low Power Wireless Applications." Doctoral thesis, Kista : KTH School of Information and Communication Technology, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-4774.
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Johnson, Kathryn E. "From Analog to Digital Control: A Study of the Russian Experience with Communications Technologies." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1397610782.
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Zhao, Shaohua. "The design of transmitter/receiver and high speed analog to digital converters in wireless communication systems : a convex programming approach /." Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B41290525.
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Wang, Mingzhen. "High-speed Low-voltage CMOS Flash Analog-to-Digital Converter for Wideband Communication System-on-a-Chip." Wright State University / OhioLINK, 2007. http://rave.ohiolink.edu/etdc/view?acc_num=wright1189815482.
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Chuang, Kevin. "Multi-gigabit CMOS analog-to-digital converter and mixed-signal demodulator for low-power millimeter-wave communication systems." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/47814.
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The objective of the research is to develop high-speed ADCs and mixed-signal demodulator for multi-gigabit communication systems using millimeter-wave frequency bands in standard CMOS technology. With rapid advancements in semiconductor technologies, mobile communication devices have become more versatile, portable, and inexpensive over the last few decades. However, plagued by the short lifetime of batteries, low power consumption has become an extremely important specification in developing mobile communication devices. The ever-expanding demand of consumers to access and share information ubiquitously at faster speeds requires higher throughputs, increased signal-processing functionalities at lower power and lower costs. In today’s technology, high-speed signal processing and data converters are incorporated in almost all modern multi-gigabit communication systems. They are key enabling technologies for scalable digital design and implementation of baseband signal processors. Ultimately, the merits of a high performance mixed-signal receiver, such as data rate, sensitivity, signal dynamic range, bit-error rate, and power consumption, are directly related to the quality of the embedded ADCs. Therefore, this dissertation focuses on the analysis and design of high-speed ADCs and a novel broadband mixed-signal demodulator with a fully-integrated DSP composed of low-cost CMOS circuitry. The proposed system features a novel dual-mode solution to demodulate multi-gigabit BPSK and ASK signals. This approach reduces the resolution requirement of high-speed ADCs, while dramatically reducing its power consumption for multi-gigabit wireless communication systems.
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Delaunay, Nicolas. "Linearization of a transmitter using an IC digital/analog cartesian feedback in 65nm CMOS for advanced communication standards." Thesis, Bordeaux 1, 2012. http://www.theses.fr/2012BOR14716/document.
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Depuis la première génération de téléphone mobile, de nombreuses fonctions et outils ont été intégrés dans nos terminaux. Il y a vingt ans, nous utilisions nos téléphone pour émettre des appels et envoyer/recevoir des messages. Aujourd’hui, l’accès à internet, la radio, l’appareil photo, des jeux et de la musique sont des fonctionnalités que l’on retrouve dans nos téléphones mobiles.Dans un contexte de téléphonie pouvant adresse plusieurs standards, l’objectif de cette thèse est de concevoir et de réaliser l’implémentation d’une architecture capable d’améliorer la linéarité de notre émetteur pour le standard 3G, utilisant des composants analogiques et numériques. Pour cela, notre étude se concentrera sur l’amélioration de la linéarité, tout en maintenant une consommation la plus faible possible mais également tout en évitant d’augmenter la taille d’une puce 3G. Nous allons démontrer qu’il est possible d’intégrer une technique de linéarisation tout en maintenant une consommation et une surface en silicium.Le premier chapitre présente différentes architectures d’émetteurs et des techniques de linéarisation avec leurs avantages et inconvénients. Il est également présenté des moyens d’évaluer l’efficacité d’un émetteur par des simulations ou des mesures. L’objectif de cette partie est de choisir une technique de linéarisation à laquelle nous associerons une architecture d’émetteur afin de répondre le plus rigoureusement à notre application et ces contraintes émanant.Le second chapitre détaille le fonctionnement du système complet, la partie numérique et la partie analogique, s’appuyant sur des études théoriques. Nous commencerons en détaillant les contraintes et les précautions qui doivent être prises en compte par le concepteur afin d’étudier l’instabilité et le bruit produit par l’émetteur. Nous décrierons alors deux algorithmes numériques permettant de réaliser la correction des signaux. Des simulations au niveau système de la boucle Cartésienne seront également présenté utilisant, dans un premier temps un amplificateur de puissance idéal, pour ensuite utilisé un amplificateur de puissance réalisé en technologie BiCMOS, et finalement un amplificateur de puissance conçu en technologie CMOS, qui est celle choisie pour notre étude.Le troisième chapitre présente la synthèse de la partie numérique en technologie CMOS des deux algorithmes précédemment cités, elle prend en compte toutes les étapes ; du code VHDL jusqu’au layout, permettant de réaliser un circuit numérique. Ensuite, il est décrit chaque composant de la boucle cartésienne, avec leurs propres simulations ou mesures. De plus, il est important de garder à l’esprit que l’objectif de cette thèse repose sur l’intégration du système complet (partie analogique et numérique) en technologie CMOS 65nm de STMicroelectronics, démontrant ainsi la faisabilité de la solution.Dans un premier temps, nous décrirons la partie numérique permettant de réaliser les étapes de correction de phase et de soustraction des signaux en technologie ASIC. L’algorithme de CORDIC a pour avantage de minimiser la consommation et l’occupation en Silicium de la partie analogique. Par la suite, l’architecture et les spécifications de chaque brique de base constituant la partie analogique seront présentées. Dans notre cas, la chaîne directe est composée de filtres, de mélangeurs, et d'un amplificateur de puissance. Notre objectif est de réaliser ces trois fonctions avec le minium de consommation et une surface du circuit la plus faible possible, ceci permettant une intégration plus aisée.Finalement, les simulations système seront présentées utilisant le logiciel de simulation ADC (Advanced Design Software) d’Agilent pour la partie analogique. Des co-simulations ont été réalisées sur le système complet, utilisant SystemVue pour la partie numérique. Les simulations réalisant ADS nous ont fourni les performances de chaque brique de base s’appuyant sur les caractéristiques des transistorsSince the first generation of mobile phones, a lot of functions, standards and tools have been integrated on handsets. Twenty years ago, consumers could use their mobile phones only to call and to send messages. Nowadays, internet access, radio, cameras, games and music are included and available as options for every mobile phone.All of these new services make the cost of production for a cellular phone more expensive. Despite that, industry has to find a solution to maintain their products the most attractive as possible including the large range of integrated functions.In the context of interaction with other standards, the aim of this thesis is to design and implement a chipset able to improve the linearity of a transmitter for third generation mobile phones, using both digital and analog technologies. For this purpose, the study will focus on the improvement of the linearity, keeping the consumption and the die area of the circuit as small as possible. We will prove that linearization on an integrated circuit is possible with almost the same consumption and die area occupation compared to a classic transmitter.The first chapter presents the different architectures used for a transmitter and various linearization techniques with their advantages and drawbacks. Some metrics are also presented in order to evaluate these architectures. The goal of this part is to choose a linearization technique associated to a transmitter in order to fit with our application and constraints.The second chapter explains the complete system, digital and analog parts, with theoretical studies. We will start by detailing the constraints and precautions that must be taken into account by the designer to study the instability and the noise generated by the transmitter. We will describe how two algorithms make signal corrections. In the last part we will show system level simulations of the Cartesian Feedback using, first, an ideal power amplifier (PA), then, a PA in a BiCMOS technology, and finally, a PA in a CMOS technology that will be used for the final integrated circuit.The third and last chapter shows the digital synthesis in a CMOS technology of the two algorithms previously mentioned, considering all steps, from the VHDL code until the layout of the digital part. We will describe and simulate each analog building block of the Cartesian Feedback, with the measurement results for some of them. Each chapter will be working towards the goal of this study, demonstrated in this part: to make an integrated system, with its complete solution and simulations.This chapter presents the integration of the analog and digital Cartesian Feedback described previously in 65nm CMOS technology from STMicroelectronics. First, the digital part generating the phase correction and subtraction will be shown in ASIC technology, with a CORDIC algorithm to reduce its consumption and size. Secondly, the architecture and specification of building blocks will be shown. In our case, the direct path is composed of filters, RF modulator and a Power Amplifier. Our objective is to design these three functions to minimize the consumption and the silicon area of the integrated architecture. Finally, system level simulations will be presented using the ADS (Advanced Design Software) from Agilent for the analog part. Co-simulations have been done to analyze the whole system, with SystemVue for the digital part. The simulations using ADS will provide the performance of each building block on the transistors level
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al-Sarʻāwī, Said Fares. "Design techniques for low power mixed analog-digital circuits with application to smart wireless systems /." Title page, contents and abstract only, 2003. http://web4.library.adelaide.edu.au/theses/09PH/09pha461.pdf.
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Nilsson, Johan, and Mikael Rothin. "Live Demonstration of Mismatch Compensation for Time-Interleaved ADCs." Thesis, Linköpings universitet, Elektroniksystem, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-78709.
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The purpose of this thesis is to demonstrate the effects of mismatch errors that occur in time-interleaved analog-to-digital converters (TI-ADC) and how these are compensated for by proprietary methods from Signal Processing Devices Sweden AB. This will be demonstrated by two different implementations, both based on the combined digitizer/generator SDR14. These demonstrations shall be done in a way that is easy to grasp for people with limited knowledge in signal processing. The first implementation is an analog video demo where an analog video signal is sampled by such an TI-ADC in the SDR14, and then converted back to analog and displayed with the help of a TV tuner. The mismatch compensation can be turned on and off and the difference on the resulting video image is clearly visible. The second implementation is a digital communication demo based on W-CDMA, implemented on the FPGA of the SDR14. Four parallel W-CDMA signals of 5 MHz are sent and received by the SDR14. QPSK, 16-QAM, and 64-QAM modulated signals were successfully sent and the mismatch effects were clearly visible in the constellation diagrams. Techniques used are, for example: root-raised cosine pulse shaping, RF modulation, carrier recovery, and timing recovery.
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Zhao, Shaohua, and 趙少華. "The design of transmitter/receiver and high speed analog to digital converters in wireless communication systems: a convex programming approach." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B41290525.
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Cho, Sunghwan. "Cooperative analog and digital (CANDI) time synchronization protocol for large multi-hop networks." Thesis, Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/42915.
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For large multihop networks, the time synchronization (TS) error accumulates as the hop number increases with conventional methods, such as Timing-sync Protocol for Sensor Networks (TPSN), Reference Broadcast Synchronization (RBS), and Flooding Time Synchronization Protocol (FTSP). In this paper, to reduce the number of hops to cover the large network and exploit the spatial averaging of TS error between clusters, a novel method combining Concurrent Cooperative Transmission (CCT) and Semi-Cooperative Spectrum Fusion (SCSF) is proposed.
This novel method named Cooperative Analog and Digital (CANDI) Time Synchronization protocol consists of two phases: The digital stage and the analog stage. The digital stage uses CCT to broadcast TS packet containing the time information. Cooperating nodes transmit the digitally encoded message in orthogonal channels simultaneously, so the receiver combines the multiple packet to acheive significant SNR advantage.
In the analog stage, the cooperating nodes simultaneously transmit their slightly different individual estimates of the propagation time by using frequency shift modulation. Nodes receiving this signal combat fading and reduce estimation error in one step through the averaging inherent in diversity combining. Simulation results for two-dimension (2-D) networks are given to evaluate the performance of CANDI, and CANDI is compared with TPSN.
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Lee, Sang Min. "A CMOS analog pulse compressor with a low-power analog-to-digital converter for MIMO radar applications." Diss., Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/42875.
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Multiple-input multiple-output (MIMO) radars, which utilize multiple transmitters and receivers to send and receive independent waveforms, have been actively investigated as a next generation radar technology inspired by MIMO techniques in communication theory. Complementary metal-oxide-semiconductor (CMOS) technology offers an opportunity for dramatic cost and size reduction for a MIMO array. However, the resulting formidable signal processing burden has not been addressed properly and remains a challenge. On the other hand, from a block-level point of view, an analog-to-digital converter (ADC) is required for mixed-signal processing to convert analog signals to digital signals, but an ADC occupies a significant portion of a system's budget. Therefore, improvement of an ADC will greatly enhance various trade-offs. This research presents an alternative and viable approach for a MIMO array from a system architecture point of view, and also develops circuit level improvement techniques for an ADC.
This dissertation presents a fully-integrated analog pulse compressor (APC) based on an analog matched filter in a mixed signal domain as a key block for the waveform diversity MIMO radar. The performance gain of the proposed system is mathematically presented, and the proposed system is successfully implemented and demonstrated from the block level to the system level using various waveforms. Various figures of merit are proposed to aid system evaluations. This dissertation also presents a low-power ADC based on an asynchronous sample-and-hold multiplying SAR (ASHMSAR) with an enhanced input range dynamic comparator as a key element of a future system. Overall, with the new ADC, a high level of system performance without severe penalty on power consumption is expected.
The research in this dissertation provides low-cost and low-power MIMO solutions for a future system by addressing both system issues and circuit issues comprehensively.
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Kolarčík, Matúš. "Distribuovaný měřicí systém s tlakoměry." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2009. http://www.nusl.cz/ntk/nusl-217973.
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This master thesies deals about pressure sensors producing by Honeywell and their applications in distributed measuring system. It deals also about base specifications from personal sensors of blood pressure, barometric hypsometer to 500 m, sensors of relative air velocity to 350km/h.
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Matinpour, Babak. "Design and development of compact and monolithic direct conversion receivers." Diss., Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/14991.
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Tsai, Tsung-Heng. "Time-interleaved analog-to-digital converters for digital communications /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2005. http://uclibs.org/PID/11984.
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Feitosa, Deisy Fernanda. "A televisão na era da convergência digital das mídias. Uma reflexão sobre a comunicação comunitária." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/27/27152/tde-24112015-101553/.
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Com o sistema binário e a convergência digital das mídias, dispositivos de comunicação como celulares, computadores e até mesmo aparelhos receptores de televisão deixam de desempenhar apenas a função principal para a qual foram desenvolvidos e passam a se constituir, devido à interoperabilidade de sistemas e à internet, em meios para os quais confluem serviços e linguagens. Se olharmos especialmente para a televisão, notaremos imediatamente que a forma de vê-la ganha novos moldes. O aparelho separa-se do conteúdo. O sinal da TV deixa seu corpo físico e passa a navegar pelo horizonte binário. Ela fica, assim, emancipada do seu corpo material - o aparelho televisor -, e pode ser acompanhada em outras plataformas e dispositivos, aumentando, desse modo, a sua difusão e as possibilidades de canal de retorno para emissores e receptores. Esta pesquisa acompanha o cenário de implantação da TV digital no Brasil e no mundo e reflete acerca das influências e transformações trazidas ao cotidiano da sociedade e aos espaços públicos pelo sistema digital e pela internet. A tese foi estruturada em cinco capítulos, que perpassam diferentes aspectos relacionados à televisão: a sua história e cronologia, os princípios tecnológicos que regem o seu funcionamento, as linguagens que a caracterizam, a sua colocação no cenário convergente e a sua influência no cotidiano das pessoas. No trabalho, trago o resultado de um estudo de caso realizado no ano de 2014, durante um Estágio de Pesquisa no Exterior na Universidade Sapienza de Roma e uma visita técnica às universidades de Brighton e Portsmouth. Essa etapa da pesquisa permitiu-me conhecer in loco o panorama atual desses países, dois anos após a conclusão do switch off, analisar a relação dos italianos e ingleses com a mídia televisiva e com as outras mídias de comunicação digital e a relação/abertura das suas emissoras televisivas para com as novas modalidades de transmissão de conteúdos nas plataformas digitais. Para isso, além buscar fontes bibliográficas, entrevistei pesquisadores e profissionais da área de radiodifusão e telecomunicações que participaram diretamente do processo de transição analógico-digital da TV. Na tese, também faço o relato de uma pesquisa de campo realizada na zona leste de São Paulo, desenvolvida em conjunto com educadores e educandos do Intermídia Cidadã, um coletivo pertencente ao Núcleo de Comunicação Comunitária da Fundação Tide Setubal. A experiência, realizada com base na Produção Partilhada do Conhecimento, serviu para divulgar a chegada da televisão digital e do apagão analógico, refletir sobre os conteúdos da TV aberta brasileira e observar as possibilidades trazidas pela TV digital para o exercício da comunicação comunitária. A pesquisa, de cunho qualitativo e quantitativo, empregou os métodos de procedimento experimental e comparativo e levantou dados através de questionário, entrevistas em áudio e vídeo, oficinas, debates e consultas bibliográficas. Dentre os autores citados, posso destacar: Mikhail Bakhtin, Lúcia Santaella, Sérgio Bairon, Arlindo Machado, Jesús Martín-Barbero, Gérman Rey, Nicholas Negroponte, Arlindo Machado, Eugênio Bucci, Manuel Castells, Clay Shriky, Henry Jenkins, Alberto Marinelli, Néstor García Canclini, Almir Almas, Jay David Bolter, Richard Grusin, Walter Benjamin, Rafael Ruiz e Márcia Tiburi.With the emergence of the binary system and the convergence of digital media, communication devices such as cellular phones, computers and even television receivers have now taken on more than just the main functions for which each was developed. They are now part of, due to the interoperability between systems and the Internet, systems of which services and languages are now integrated to as well. If one was to focus entirely on television, it can be observed that television watching has now received new forms. The device itself is separate from the content. The TV signal moves away from its physical form and begins to navigate on the binary field. Thus, it is emancipated of its material form - the television device - and can now be seen on other platforms and devices, hence raising the signal\'s distribution and the possibilities of return channels to transmitters and receivers. This research has closely followed the digital television implementation scenario in Brazil and in the world, and observes the influences and transformations in introduced to society\'s daily routine and to the public arena by the digital system and the Internet. The thesis is structured in five parts that run through the different aspects related to television: its timeline and history, the technological principles that command its operation, the languages that distinguish it, its placement in the converging scenario, and is influence in society\'s daily routine. This project presents the result of a case study performed in 2014, during my Research Internship at the University of Sapienza, in Rome. It also includes data gathered during technical visits to the universities in Brighton and Portsmouth. This stage of the research allowed me to observe the current panorama of these countries in loco, two years after the switch off. It also gave me the opportunity to analyze the relationship of the Italians and the English with television media, as well as with other digital communications media and the relationship/opening of the television transmitters of each country to new transmission modalities of content on digital platforms. In order to perform this leg of the research, in addition to searching in bibliographical sources, I interviewed researchers and professionals of the radio broadcasting and telecommunications fields, who had directly participated in the analogue-digital TV transition process. In this thesis, I also present a report of a field study done in the East Side of São Paulo city. This study was developed with the help of educators and pupils of Intermídia Cidadã, a collaboration that belongs to the Community Communication Nucleus of the Tide Setubal Foundation. The experience, based on the Shared Production of Information, was helpful to showcase the arrival of digital television and the analogue blackout. It was also useful to consider the content of public TV in Brazil and to analyze the possibilities now available through digital TV for community communication. This research, of qualitative and quantitative intent, applied comparative and experimental methods and collected data through surveys, audio and video interviews, workshops, debates and bibliographic research. Among the authors mentioned, I would like to make special reference to the following: Mikhail Bakhtin, Lúcia Santaella, Sérgio Bairon, Arlindo Machado, Jesús Martín-Barbero, Gérman Rey, Nicholas Negroponte, Arlindo Machado, Eugênio Bucci, Manuel Castells, Clay Shriky, Henry Jenkins, Alberto Marinelli, Néstor García Canclini, Almir Almas, Jay David Bolter, Richard Grusin, Walter Benjamin, Rafael Ruiz and Márcia Tiburi.
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Hessle, Adam. "Dr. Syntlove eller, Hur jag slutade ängslas och lärde migfärga digitala syntar : En snåljåps guide till det dyra syntersizerljudet." Thesis, Högskolan Dalarna, Ljud- och musikproduktion, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:du-27274.
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Uppsatsen presenterar en undersökning av skillnaden mellan analoga hårdvarusyntar och digitala mjukvarusyntar. Syftet är att färga de digitala mjukvarusyntarna så dessa efterliknar de analoga hårdvarusyntarna. Detta kan gynna situationer där man som Musik och Ljudproducent önskar efterlikna en analogsynt med digitala verktyg och medel. Tidigare forskning redogör hur signalerna från syntar upplevs. Efter mätningslabbar visade det sig att analoga hårdvarusyntar hade grövre vågformer, därav beslöt man sig för bitdjupsreducering som metod för att färga ljuden. Dock så visade sig bitdjupsreducering inte vara en tillräckligt färgande metod. Resultaten talade för att lyssnaren fortfarande kunde urskilja signalerna trots behandling.
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Niklasson, Daniel, and Filip Zizak. "Teknikens påverkan på filmfotografens yrkesroll : En kvalitativ intervjustudie om filmfotografens kreativa arbetsprocess." Thesis, Högskolan Dalarna, Bildproduktion, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:du-24225.
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Den här uppsatsen undersöker hur filmfotografens yrkesroll och kreativitet påverkas av valet av teknik. Trots att det snart gått 20 år sedan digitala kameror började användas i filmproduktioner används än idag analoga kameror i stor utsträckning. Kameran är fotografens viktigaste verktyg och den här uppsatsen belyser skillnader i arbetsprocessen med analog och digital film samt hur detta påverkar filmfotografens kreativa process. Vi har genomfört kvalitativa intervjuer med fyra filmfotografer som har arbetat med både analog och digital film och med hjälp av dessa genomfört en diskursanalys. Resultatet visar att det finns skillnader i arbetet med analog och digital teknik. Det finns dock lika mycket för- som nackdelar med de båda teknikerna och de lämpar sig bäst i olika typer av produktioner. Det går inte att säga att fotografen kan vara mer eller mindre kreativ beroende på vilken teknik som används. Teknikvalet påverkar fotografen främst i det tekniska arbetet men nödvändigtvis inte i den kreativa processen.
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Shehata, Ahmed Alaael-Din Rohiem. "Secure computer communications and databases using chaotic encryption systems." Thesis, University of Kent, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.324713.
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Berggren, Wiklund Manne. "Same as it never was : Det analoga fotografiet och dess fält i en digital tid." Thesis, Umeå universitet, Institutionen för kultur- och medievetenskaper, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-186421.
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This study examines the culture and values surrounding the analogue camera and the analogue photography today. The aim is to answer the questions of how the field of analogue photography look like? Why it still exist? And what the role of analogue photography in a digital context is? Through qualitive interviews with six persons who practices analogue photography the study examines their field, and reasons for choosing it over digital. Based on theories by Pierre Bourdieu the analysis shows the fields positions of power, and identifies the capitals that are valued and why they are valued. The interviewees describes the benefits of the analogue in relation to digital photography as more valuable and more esthetic. They say that the randomness and imperfections of the analogue has artistic and esthetic qualities and advantages. The study connects this with analogue nostalgia, and Hartmut Rosas theory of resonance. With a theoretical framework based on Zygmunt Bauman and Christopher Lasch the study analyzes analogue photography in a digital context. The study finds that analogue photography is nostalgic in the sense that it is practiced in relation to the digital, and in some cases as a way to escape and oppose digital society. Further the study suggests that when the interviewees uses analogue photography to oppose the digital in favor of the wellbeing of oneself, it could on the other hand be a practice in conformity with modern society despite the interviewees efforts to oppose it.
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Cekceoglu, Engin. "Communicating Corporate Identity Through Form Attributes And Evaluating Visual Analogy Of Digital Cameras." Master's thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607864/index.pdf.
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The basic notion of this study is related with visual attributes of products which reflect the identity of the company as well as form and design consistency which is a factor forming corporate identity. The sub-notions of the topic are elaborated in the literature review. The efforts which aimed at finding out the distinguishing characteristics of products focused on certain sample products. Digital camera is selected for the field study. The objective of the study is to put evidence that firms can be distinguished from each other with the help of visual attributes of their products and to determine which factors are effective throughout this process.
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Bittle, Charles C. "Linearity and monotonicity of a 10-bit, 125 MHz, segmented current steering digital to analog converter." Thesis, University of North Texas, 2000. https://digital.library.unt.edu/ark:/67531/metadc2541/.
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The purpose of this research is to determine the linearity and monotonicity of the THS5651IDW digital to analog converter (DAC), a prototype of the future Texas Instruments TLV5651, 10-bit, 125 MHz communication DAC. Testing was conducted at the Texas Instruments facility on Forest Lane, Dallas, Texas. Texas Instruments provided test equipment, software and laboratory space to obtain test data. Analysis of the data found the DAC to be monotonic since the magnitude of the differential nonlinearity (DNL) was less than ± 1 least significant bit (LSB) and the integral nonlinearity (INL) was less than ± 0.5 LSB. The study also showed that the DAC has primarily negative DNL although the DNL is well within the desired specification.
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Douglas, Dale Scott. "Flicker noise in cmos lc oscillators." Thesis, Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/26550.
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Sources of flicker noise generation in the cross-coupled negative resistance oscillator (NMOS, PMOS, and CMOS) are explored. Also, prior and current work in the area of phase noise modeling is reviewed, including the work of Leeson, Hajimiri, Hegazi, and others, seeking the mechanisms by which flicker noise is upconverted.
A Figure of Merit (FOM) methodology suitable to the 1/f3 phase noise region is also developed, which allows a new quantity, FOM1, to be defined. FOM1 is proportional to flicker noise upconverted, thus allowing the effectiveness of flicker noise upconversion suppression techniques to be evaluated, despite possibly changing bias points or tank Q, which would change phase noise and FOM in the 1/f2 region.
The work of Hajimiri is extended with a simple Amplitude ISF DC component estimator for the special case of LC CMOS oscillators. A method of adaptive control of an oscillator core is presented, as well, comprised of a CMOS oscillator with a digitally adjustable N and P width, and a circuit (which is essentially a tracking ADC) which repeatedly adjusts the relative N to P width dependent on the estimate to maintain the condition of minimum flicker noise upconversion. A fixed calibration constant is sufficient to allow convergence to within 0.7dB of optimal FOM1 for all cases of N width, for a varactorless oscillator test cell.
Finally, a circuit is proposed which would allow the flicker noise reduction technique of cycling to accumulation to be applied to continuous time oscillators, but is not rigorously vetted.
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Angle, Emelie. "Spår av den mänskliga handen : Analog och digital animation." Thesis, Högskolan i Skövde, Institutionen för informationsteknologi, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-18689.
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Med utgångspunkt i den analoga animationsstilen ”rubber hose” från tidigt 1900-tal undersöker den här uppsatsen vilka spår av den mänskliga handen som människor uppfattar i analog respektive digital animation. Hur värdesätter man de två olika sätten att animera och vilken syn har man på rubber hose som animationsstil? Två nygjorda animationer i rubber hose-stilen, skapade analogt respektive digitalt, samt en autentisk animation av karaktären Mickey Mouse är utgångspunkten i en enkätundersökning med följande forskningsfrågor och svar: Hur ser respondenterna på rubber hose-stilen? Rubber hose är fortfarande bekant och uppfattas som relevant men inte nödvändigtvis i analogt animerad form. Vilka eventuella spår av animatören uppfattade respondenterna i den analoga respektive digitala animationen? Skärpa, pennstreck och bakgrundens ”smutsighet” är några exempel på upplevda spår av animatören i de analoga animationerna. Dock har respondenterna svårare att uppfatta spår i den digitala animationen. Hur påverkas respondenternas upplevelse av en animation av om den är analoga eller digital? En majoritet av respondenterna anser att den digitala animationen har högra kvalité men att den analoga har charm och ger nostalgi. En slutsats man kan dra av undersökningen är att rubber hose-stilen fortfarande uppskattas men att animatören genom att åtminstone delvis ta till digitala medel både kan underlätta processen och behålla känslan
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Huang, Hao [Verfasser], and Manfred [Akademischer Betreuer] Berroth. "Ultra-high-speed digital-to-analog converter for optical communications / Hao Huang ; Betreuer: Manfred Berroth." Stuttgart : Universitätsbibliothek der Universität Stuttgart, 2019. http://d-nb.info/119821323X/34.
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Chiu, Leung Kin. "Efficient audio signal processing for embedded systems." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/44775.
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We investigated two design strategies that would allow us to efficiently process audio signals on embedded systems such as mobile phones and portable electronics. In the first strategy, we exploit properties of the human auditory system to process audio signals. We designed a sound enhancement algorithm to make piezoelectric loudspeakers sound "richer" and "fuller," using a combination of bass extension and dynamic range compression. We also developed an audio energy reduction algorithm for loudspeaker power management by suppressing signal energy below the masking threshold. In the second strategy, we use low-power analog circuits to process the signal before digitizing it. We designed an analog front-end for sound detection and implemented it on a field programmable analog array (FPAA). The sound classifier front-end can be used in a wide range of applications because programmable floating-gate transistors are employed to store classifier weights. Moreover, we incorporated a feature selection algorithm to simplify the analog front-end. A machine learning algorithm AdaBoost is used to select the most relevant features for a particular sound detection application. We also designed the circuits to implement the AdaBoost-based analog classifier.
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Rudvi, Emil. "Digital Game Mechanics : to create an analog board game prototype." Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-3282.
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Analog games misses a lot of quick games in terms of game time and play time in the FPS genre. This genre often takes more time to play in an analog game. Could the game play become quicker by examining the different game mechanics in order to give the players a smoother game play by a reduction of downtime. Game mechanics that could be found in a digital FPS game such as Doom III, were converted to a prototype. These digital gameplay mechanics were converted so that an analog game could be played simultaneously. These game mechanics decrease the game time and down time in a way that a game using a turn based game order would not. The digital game Doom III was used to create the prototype and eight analog games of different types and genres were examined to collect more unique game mechanics. All were suited for a multiplayer type of gameplay. To get an understanding of what game elements were well liked in both digital and analog games, a questionnaire was created with twelve questions. The participants answered questions on the subjects of their favourite genre, missing game mechanics in both digital and analog games, well liked game mechanics, and also what the participants thought was impossible to create in a game in terms of game mechanics. The results of both the analysis of the eight analog games and the answers from the participants created the base plan for the development of the prototype focusing on low downtime, re-playability, and an average amount of luck. Several game mechanics were discussed and some of them were play tested. This resulted in keeping some game mechanics while others were removed because these game mechanics did not provide a rewarding gameplay. Several game mechanics were nearly impossible to implement without the use of a digital representation. An example on this type of issue was the first person view in the digital game. The perception of skill based game mechanics could be moved to an analog board game but would have to be determined by other game mechanics instead of the player’s physical capabilities. The conclusion lead to a prototype that could be played in an hour, which is a low game time for games in this genre. The FPS gameplay mechanics was converted to an analog game, but all game mechanics could not be transferred to the prototype without a conversion.Gränsvägen 29 372 37 Ronneby Phone +46(0)708 35 04 45
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Azevedo, Daniel Filipe Pinheiro de. "Performance comparison of hybrid architectures for millimeter wave communicatins." Master's thesis, Universidade de Aveiro, 2016. http://hdl.handle.net/10773/16945.
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Mestrado em Engenharia Electrónica e TelecomunicaçõesA proliferação massiva das comunicações sem os faz prever que o número de utilizadores aumente exponencialmente até 2020, o que tornar a necessário um suporte de tráfego milhares de vezes superior e com ligações na ordem dos Gigabit por segundo. Este incremento exigir a um aumento significativo da e ciência espectral e energética. Impõe-se portanto, uma mudança de paradigma dos sistemas de comunicação sem os convencionais, imposta pela introdução da 5a geração. Para o efeito, e necessário desenvolver novas e promissoras técnicas de transmissão, nomeadamente a utilização de ondas milimétricas em sistemas com um número massivo de antenas. No entanto, consideráveis desafios emergem ao adotar estas técnicas. Por um lado, este tipo de ondas sofre grandes dificuldades em termos de propagação. Por outro lado, a adoção de arquiteturas convencionais para sistemas com um número massivo de antenas e absolutamente inviável, devido ao custo e ao nível de complexidade inerentes. Isto acontece porque o processamento de sinal ao nível da camada f sica e maioritariamente feito em banda base, ou seja, no domínio digital requerendo uma cadeia RF por cada antena. Neste contexto as arquiteturas híbridas são uma proposta relativamente recente que visa simplificar a utilização de um grande número de antenas, dividindo o processamento entre os domínios analógico e digital. Para além disso, o número de cadeias RF necessárias e bastante inferior ao número total de antenas do sistema, contribuindo para obvias melhorias em termos de complexidade, custo e energia consumida. Nesta dissertação e implementada uma arquitetura híbrida para ondas milimétricas, onde cada cadeia RF está apenas conectada a um pequeno conjunto de antenas. E considerado um sistema contendo um transmissor e um recetor ambos equipados com um grande número de antenas e onde, o número de cadeias RF e bastante inferior ao número total de antenas. Pré-codificadores híbridos analógico/digital, recentemente propostos na literatura são utilizados e novos equalizadores híbridos analógico/digital são projetados. E feita uma avaliação de performance à arquitetura implementada e posteriormente comparada com uma outra arquitetura, onde todas as antenas estão conectadas a todas as cadeias RF.
The expected massive proliferation of wireless systems points out an exponential increase in the number of users until 2020, which is needed to support up to one thousand times more tra c and connections in order of Gigabit per second. However, these goals require a signi cantly improvement in the spectral and energy e ciency. As a result, it is essential to make a paradigm shift in conventional wireless systems, imposed by the introduction of fth generation (5G). For this purpose, new and promising transmission techniques will be needed, namely the use of millimeter Waves (mmWave) in systems with a massive number of antenna elements. Nevertheless, considerable challenges emerge in the adoption of these techniques. On one hand, mmWave su er great di culties in terms of propagation. On the other hand, the using of conventional architectures for systems with a large number of antennas is absolutely impracticable because of the costs and the level of complexity. This happens because the signal processing in physical layer is mostly done in baseband, which means, that one RF chain for each antenna is required. In this context the hybrid architectures are a relatively recent proposal where the aim is to simplify the use of a large number of antenna elements, dividing the processing between the analog and digital domains. Moreover, the number of RF chains needed are much lower than the total number of antenna elements of the system, which contribute to obvious improvements in terms of complexity, costs and energy consumption. In this Dissertation a hybrid mmWave based architecture, where each RF chain is only connected to a small set of antennas, is implemented. It is considered a system comprising a transmitter and a receiver both equipped with a massive number of antennas and where the number of RF chains is much lower than the number of antennas. Hybrid analog/digital precoders recently proposed in the literature are used and a new hybrid analog/digital equalizer is designed. The implemented architecture is then evaluated and compared with other architecture, where all the antennas are connected to all RF chains.
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Maciejewski, Robert. "Privacy aspects of digital communication." St. Gallen, 2007. http://www.biblio.unisg.ch/org/biblio/edoc.nsf/wwwDisplayIdentifier/01665892002/$FILE/01665892002.pdf.
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Anderson, Christopher R. "A Software Defined Ultra Wideband Transceiver Testbed for Communications, Ranging, or Imaging." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/29026.
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Impulse Ultra Wideband (UWB) communications is an emerging technology that promises a number of benefits over traditional narrowband or broadband signals: extremely high data rates, extremely robust operation in dense multipath environments, low probability of intercept/detection, and the ability to operate concurrently with existing users. Unfortunately, most currently available UWB systems are based on dedicated hardware, preventing researchers from investigating algorithms or architectures that take advantage of some of the unique properties of UWB signals.
This dissertation outlines the development of a general purpose software radio transceiver testbed for UWB signals. The testbed is an enabling technology that provides a development platform for investigating ultra wideband communication algorithms (e.g., acquisition, synchronization, modulation, multiple access), ranging or radar (e.g., precision position location, intrusion detection, heart and respiration rate monitoring), and could potentially be used in the area of ultra wideband based medical imaging or vital signs monitoring. As research into impulse ultra wideband expands, the need is greater now than ever for a platform that will allow researchers to collect real-world performance data to corroborate theoretical and simulation results.
Additionally, this dissertation outlines the development of the Time-Interleaved Analog to Digital Converter array which served as the core of the testbed, along with a comprehensive theoretical and simulation-based analysis on the effects of Analog to Digital Converter mismatches in a Time-Interleaved Sampling array when the input signal is an ultra wideband Gaussian Monocycle. Included in the discussion is a thorough overview of the implementation of both a scaled-down prototype as well as the final version of the testbed. This dissertation concludes by evaluating the of the transceiver testbed in terms of the narrowband dynamic range, the accuracy with which it can sample and reconstruct a UWB pulse, and the bit error rate performance of the overall system.Ph. D.
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Gutiérrez, Campo Ana María. "Development of integrated silicon photonics modulation devices for digital and analog applications." Doctoral thesis, Universitat Politècnica de València, 2013. http://hdl.handle.net/10251/33330.
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Silicon photonics is one of the most exciting and fastest growing photonic technologies
in recent years. The salient feature of this technology is its compatibility with the
mature silicon IC manufacturing based on complementary metal-oxide semiconductor
(CMOS) processes widely used in microelectronic industry. Another motivation is the
availability of high-quality silicon-on-insulator (SOI) planar waveguide circuits that
offer strong optical confinement due to the high index contrast between silicon (n=3.45)
and SiO2 (n=1.45). This opens up miniaturization and very large scale integration of
photonic devices allowing photonic integrated circuits for a wide range of applications
and markets, from optical telecommunications to bio-photonic devices or precise fibre
sensors. Optical modulators are key building-blocks for high speed signal transmission
and information processing in any photonic interconnection solution. The work
developed in this thesis, as part of the objectives of the European project HELIOS in
which it is framed, is essentially focused on realizing compact and efficient modulators
integrated on silicon chips.
The thesis consists of three main chapters as well as the concluding section on the
work accomplished. Chapter one is aimed at giving a general description of the benefits
of using silicon photonics, showing its challenges and opportunities as well as at giving
a deeply overview of all issues related to the electro-optic modulation. Chapter two is
devoted to develop silicon modulators with high features for digital applications.
Specifically, new optical structures different to the conventional ones are presented with
the aim of enhancing the modulation performance or at least several critical parameters
in the modulation. Chapter three is dedicated to the analog applications. The concept of
microwave photonics is described as well as different researches carried out in the
analog scope for application in the field of integrated microwave photonics, all of them
using CMOS-compatible electro-optic silicon modulators which validate the potential of
silicon photonics as a promising approach for enabling the development of integrated
microwave photonics applications. Finally, conclusions on the work realized are
provided in Chapter 4.La fotónica de silicio es una de las tecnologías fotónicas que está experimentando un crecimiento más excitante y rápido en los últimos años. La característica más destacada de esta tecnología es su compatibilidad con las maduras técnicas de fabricación de circuitos integrados de silicio basadas en los procesos ¿complementary metal-oxide semiconductor¿ (CMOS) ampliamente utilizados en la industria microelectrónica. Otra motivación es la disponibilidad de circuitos de guía de ondas planas de silicio sobre aislante (SOI) de alta calidad que ofrecen un fuerte confinamiento óptico debido al alto contraste índices entre el silicio (n=3,45) y el SiO2 (n = 1,45). Esto abre las puertas a la miniaturización y a la integración a gran escala de dispositivos fotónicos lo que resulta en circuitos fotónicos integrados para una amplia gama de aplicaciones y mercados, desde telecomunicaciones ópticas a dispositivos bio-fotónicos o sensores de fibra precisos. Los moduladores ópticos son elementos básicos fundamentales para la transmisión de señales a alta velocidad y el procesado de información en cualquier solución de interconexión fotónica. El trabajo desarrollado en esta tesis, como parte del los objetivos del proyecto Europeo HELIOS en el que está enmarcada, se centra fundamentalmente en realizar moduladores compactos y eficientes, integrados en chips de silicio. La tesis consiste en 3 capítulos principales así como una sección de conclusiones del trabajo conseguido. El capítulo uno está destinado a dar una descripción general de los beneficios del uso de la fotónica de silicio, mostrando sus retos y oportunidades, así como a dar una visión profunda de todos los aspectos relacionados con la modulación electro-óptica. El capítulo dos está dedicado a desarrollar moduladores de silicio de altas prestaciones para aplicaciones digitales. Específicamente, se presentan nuevas estructuras ópticas diferentes a las convencionales con el objetivo de mejorar el rendimiento de la modulación o al menos algunos parámetros críticos en la modulación. El tercer capítulo se dedica a las aplicaciones analógicas. Se describe el concepto de la fotónica de microondas, así como diferentes investigaciones llevadas a cabo en el ámbito analógico para su aplicación en el campo de la fotónica integrada de microondas, todas ellas usando moduladores electro-ópticos de silicio compatibles con los procesos de fabricación CMOS, lo que valida el potencial de la fotónica de silicio como un prometedor enfoque para permitir el desarrollo de aplicaciones de la fotónica integrada de microondas. Por último, las conclusiones sobre el trabajo realizado se proporcionan en el Capítulo 4.
Gutiérrez Campo, AM. (2013). Development of integrated silicon photonics modulation devices for digital and analog applications [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/33330
TESIS
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Johansson, Anneli, and Tove Dahlström. "Diffraktion i spelgrafik;En metod för analogt och digitalt konstskapande." Thesis, Blekinge Tekniska Högskola, Institutionen för teknik och estetik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-19946.
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Konstnärens roll som forskare är svår att placera då det är svårt att hålla sig objektiv när ens forskning går ut på att undersöka ens kreativa handlingssätt som en individ.. Detta kandidatarbete har tagit ståndpunkten av en posthumanistiskt synvinkel på världen och hur vi agerar med den, speciellt genom ögonen på konstnären och ens material. Med detta i åtanke så utvecklade vi vår frågeställning kring fenomenet av diffraktion. Diffraktion är ett naturlig fenomen där vågor av ljus kolliderar och formar ett mönster där vi kan studera effekten av de skillnader som uppstår. Vår förståelse och syn på diffraktion är baserat på Donna Haraways och Karen Barads djupdykande kunskap kring området både i ett filosofiskt och vetenskapligt perspektiv. Med diffraktion som metod experimenterar och dokumenterar vi vår position och intra-aktioner med vårt konstnärliga material som en bestående partner i att materialisera en 3D miljö inuti en spelmotor. Vi och vårt material blir fokusgruppen för vår undersökning för att svara på frågan hur diffraktion kan användas som en metod för konstnärligt skapande med analoga och digitala verktyg. Denna resa dokumenteras genom anteckningar och reflektioner från våra individuella perspektiv och beskriver även vår produktionscykel för att belysa vår process och vilka metoder som implementerades i vilken del av processen. För att avsluta detta arbete så diskuterar vi även de förhållanden som uppstod i vår undersökning och hur temat och fokuset skulle kunna expandera utanför vår valda inriktning.The role of the artist as a researcher is difficult to place since it’s hard to be objective while researching your creative approach as an individual. This bachelor thesis has taken the stance of the post-humanist viewpoint on the world and how we as humans act within it, especially through the eyes of the artist and our relationship to our materials. With this in mind, we developed our research question surrounding the phenomena of diffraction. Diffraction is a natural phenomena where waves of light collide and form a pattern where we can look at the effect of the differences that occur. Our understanding and take on diffraction is based on Donna Haraway’s and Karen Barad’s deep knowledge on the subject in both a philosophical and scientific way. With diffraction as a method we experiment and document our positions and intra-actions with our artistic material as our joined partner in materializing a 3D environment within a game engine. We and our material become the research subjects to answer the question about how diffraction can become a method for artistic creation in a blend of analogue and digital art production. This journey is documented through notes and reflections from our separate perspectives and we also lay out our production cycle to display our process and which production methods are integrated where. To finish this paper, we discuss the conditions of our work and how the theme and subject of this research could be expanded upon.
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Winterstein, Andreas [Verfasser]. "Design, analysis and demonstration of a hybrid analog/digital retro-directive antenna system for satellite communications / Andreas Winterstein." Düren : Shaker, 2019. http://d-nb.info/1188553410/34.
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Hwang, Yong Goo. "Optimal configuration of digital communication network." Thesis, Monterey, California : Naval Postgraduate School, 1990. http://handle.dtic.mil/100.2/ADA243041.
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Thesis (M.S. in Computer Science)--Naval Postgraduate School, December 1990.Thesis Advisor(s): Suh, Myung W. Second Reader: Hamming, Richard W. "December 1990." Description based on title screen as viewed on March 30, 2010. DTIC Identifier(s): Program Listings, Lagrangian Relaxation. Author(s) subject terms: Network, Langrangian Relaxation, Subgradient Optimization. Includes bibliographical references (p. 66-67). Also available in print.
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Qian, Xinben Garrison. "Adaptive systems in digital communication designs." Thesis, Massachusetts Institute of Technology, 1996. http://hdl.handle.net/1721.1/38821.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 1996.Includes bibliographical references (leaves 98-100).
by Xinben Garrison Qian.
M.S.
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Gomes, Rui Miguel Soares. "Intelligent peripherals with digital communication bus." Master's thesis, Universidade de Aveiro, 2009. http://hdl.handle.net/10773/5563.
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Mestrado em Engenharia Electrónica e TelecomunicaçõesEsta dissertação é parte integral do projecto ECU2010 e é focada no desenvolvimento de Periféricos Inteligentes que são conectados à ECU através de um Barramento Digital de Comunicação. O projecto ECU2010 está centrado no desenvolvimento de uma nova arquitectura da unidade de controlo electrónico (ECU) para desporto automóvel, focada no controlo de motores de combustão interna. A arquitectura proposta deverá ser ter a capacidade de controlar um motor de combustão interna usando os mais modernos modelos de controlo, mas sendo baseada numa modelo de processamento distribuído, composta por módulos de processamento auto-suficientes ao nível de comunicações e armazenamento e de sensores/actuadores com inteligência capazes de processamento prévio de dados. A ênfase desta dissertação será colocada apenas nos Periféricos Inteligentes e no Barramento Digital de Comunicação. Este documento irá analisar e propor uma solução para a inclusão de capacidades de processamento, armazenamento e diagnóstico nos periféricos, assim como o desenvolvimento de um Barramento Digital de Comunicação que permite aos periféricos comunicarem com a ECU e sincronizarem-se com a rotação do motor.
This dissertation is an integral part of the ECU2010 project and is focused on the development of Intelligent Peripherals which connect to the ECU by means of a Digital Communication Bus. The ECU2010 project is centered on developing a new architecture of electronic control units (ECU) for motor sport, focussing on control of internal combustion engines. The proposed new architecture should be capable of controlling an internal combustion engine using the state-of-the art control models, but based on a distributed processing model consisting on self-sufficient processing modules in terms of communications, storage and intelligent enabled sensors/actuators, which is able to produce low-level data processing. The focus of this dissertation will only be the Intelligent Peripherals and the Digital Communication Bus. This document will analyse and propose a solution for the incorporation of processing, storage and diagnostic capabilities into peripherals, as well as the development of a Digital Communication Bus which allows the peripherals to communicate with the ECU and synchronize them with the engine’s rotation.
FCT; FSE
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Lashgari, Maryam. "Digital Marketing Strategy:B2B and Stakeholders Communication." Doctoral thesis, KTH, Skolan för industriell teknik och management (ITM), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-220144.
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Since digital media entered the business domain, many different tools and platforms have transformed the nature of business communications. This transformation has not been easy, since the journey has been accompanied by challenges from the marketers’ side against the adoption of the new platforms into the firm’s communication channels. Business to business marketers have also been engaged in such challenges by maintaining a slow adoption, which has motivated the researchers to study the adoption of different means and tools of digital communication in a business context. Through this research, I contribute by exploring the adoption strategies of digital platforms in the B2B supply chain including B2B firms, retailers and end users. By digital media, I mainly refer to social media and beacon technology. First, I begin this thesis by identifying the adoption and integration strategies of social media and digital marketing into traditional marketing channels in a B2B context. In this part, I identify the B2B firms’ target audience and propose a model facilitating a B2B firm’s practical social media adoption strategies. Second, to explore the benefits of different social media content sharing approaches derived from information accessibility resulted in the prior study of this thesis, I introduce and examine Public and Gated-Content sharing approaches. Thereafter, assisted by Social Power Theory and Resource Dependence Theory, I examine the effect of Public and Gated-Content sharing approaches on the target audience’s willingness to interact with the firm. The findings of this study reveal that Gated-Content approach can help the firms build closer relationship with the target audience and engage them in a co-creation process. Third, by studying proximity marketing through the adoption of beacon technology in the retail context, I explore the current methods of usage, as well as the benefits and challenges of in-store proximity marketing adoption for content sharing purposes. I complete the thesis by presenting the different challenges of such adoption, which consist technical, human behavior, managerial perception, resource and privacy factors. Finally, I identify the need to integrate the physical aspect of place and location back again into the online digital communication channels within a retail context.QC 20171219
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Ruiz, Svensson Erik, and Emma Rådhall. "Social responsibility in the digital era : Digital communication agencies social responsibility in digital channels." Thesis, Tekniska Högskolan, Högskolan i Jönköping, JTH, Datateknik och informatik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:hj:diva-46404.
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Purpose and problem discussion: Nowadays, it is crucial to implement social responsibility to business operations to succeed as a business. Companies face increased demands from customers and stakeholders to show their actions regarding social responsibility. At the same time, digital development is shaping the communication industry, creating new communication platforms in the world. The purpose of this study is to explore digital communication agencies role in the production and implementation of digital products within digital channels to best understand digital social responsibility. The study aims to answer the research questions: What social responsibilities does a digital communication agency have in regard to the products and messages they produce for digital channels? and How do digital communication agencies become socially responsible when using digital channels? Method: An abductive analysis method was applied to semi-structured interviews with digital communication agencies in Jönköping, Sweden. The analysis of the empirical findings has resulted in deeper understanding of social responsibility in digital environments; a study area that has not been explored before. Four digital communication agencies represent the average digital social responsibility mindset and business culture in Jönköping, Sweden. This gave us the possibility to research social responsibility on digital channels. Results, discussion and conclusions: The results show that the digital communication agencies clients are entirely responsible for the digital material published on their own digital channels. Although, the agencies do need to make sure they produce the best possible material for their clients to avoid bad relationships with stakeholders and a bad reputation. The results also show that social responsibility is not first priority for any company; profitability always comes first. The key to digital social responsibility is to work with the right clients and thoroughly analyse the client’s business operations to bring out the best in each case and to be prepared for backlashes. The digital communication agencies could also benefit from a crisis plan, to minimise stress and optimize the problem solving if a crisis would occur. If doing this correctly,the agencies enable genuine and honest digital communication, which minimises the risk of being perceived unfairly on digital platforms. This is especially of importance on digital platforms, where the speed, great reach and two-way communication makes it even easier to receive negativity and face backlashes. A digital communication agency can become socially responsible by working with the right clients, as well as producing and publishing genuine and honest digital communication.
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Patel, Vipul J. "A Poly-phased, Time-interleaved Radio Frequency Digital-to-analog Converter (Poly-TI-RF-DAC)." Wright State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=wright1516146989134088.
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Cooper, Katarina. "Sveriges Radio - Public Service : Den digitala vägen till nya användare." Thesis, Södertörn University College, School of Communication, Technology and Design, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-588.
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The purpose of this report was to study how the Swedish radio channel Sveriges Radio (SR) website changed over time. What are the differences between various media websites? How many people listen to normal and web-radio and what are the differences between the various services offered on the SR website?
Reports from the BBC, Statistics Sweden, Mediavision and the Swedish National Post and Telecom Agency were compared. Several theoreticians have been studied, including Donald A Norman, Jonas Löwgren, Karen Holtzbratt, Jacob Nielsen and Geoffrey Moore.
The method used by the author comprised a systematic mapping of statistics from webTrends, KiaIndex, SiteCensus, TNS Gallup/K2analys and reports from RUAB. The data studied have been collected from telephone interviews, postal surveys, internet panels, and from log files. The statistics have then been compared and in some cases tables have been cross-correlated.
The results from the various studies showed that SR is following the rising trend displayed by a few of the media websites reviewed. It is of particular interest to note that web-radio listening between the final period 2004 and 2005 almost doubled.
The next stage will be to offer the listener/user a more central position. By listening to users, and above all non-users, the function and content can be adapted to the larger group of pragmatists and conservative listeners that are looking for sustainable and convenient solutions.
Key words [Streaming, on demand, radio, analogue, web-radio]
Avsikten med den här rapporten var att ta reda på hur Sveriges Radios (SR) sajt förändras över tid. Vilka skillnader finns det mellan olika mediesajter. Hur många lyssnar på vanlig- kontra webbradio samt vad finns det för skillnader mellan olika tjänster på SR:s sajt.
Jämförelser har gjorts mellan BBC, SCB, Mediavision samt Post & Telestyrelsens rapporter. Flera teoretiker har studerats som Donald A Norman, Jonas Löwgren, Karen Holtzbratt, Jacob Nielsen och Geoffrey Moore.
Författarens metod bestod av att systematiskt kartlägga statistik från webTrends, KiaIndex, SiteCensus, TNS Gallup/K2analys samt RUAB:s rapporter. De data som undersökts kommer från telefonintervjuer, postenkäter, Internetpaneler samt loggfiler. Statistiken har jämförts med varandra samt i vissa fall har tabellerna korskörts.
Resultaten från de olika undersökningarna visar att SR följer den uppåtgående trend som några av de undersökta mediesajterna har. Men det mer intressanta är att webbradiolyssningen mellan sista perioden 2004 och 2005 nästan fördubblats.
Nästa steg blir att se till att lyssnarna/användarna står mer i centrum. Genom att lyssna på användare, men framför allt icke-användare så skulle funktion och innehåll kunna anpassas till den större gruppen pragmatiker och konservativa som vill ha hållbara och bekväma lösningar.
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Song, Nuan [Verfasser], Martin [Akademischer Betreuer] Haardt, Galdo Giovanni [Gutachter] Del, and Lamare Rodrigo C. [Gutachter] De. "Ultra Wideband Communications : from Analog to Digital / Nuan Song ; Gutachter: Giovanni Del Galdo, Rodrigo C. De Lamare ; Betreuer: Martin Haardt." Ilmenau : TU Ilmenau, 2013. http://d-nb.info/117818482X/34.
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Earnshaw, Rae A. "Digital media." IEEE, 2001. http://hdl.handle.net/10454/3507.
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YesDevelopments and advances in information and communications technology are boosting a convergence of computing, media, and telecommunications. This is dramatically affecting every aspect of society from technology designers and content creators to users. The design-to-product cycle time continues to decrease as new markets open up, and windows of opportunity exist for those who can move fast and make the right connections. Challenges and opportunities exist in each area of the convergence, but one thing is here to stay: being digital.
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Pous, Solà Marc. "Radiated transient interferences in digital communication systems." Doctoral thesis, Universitat Politècnica de Catalunya, 2015. http://hdl.handle.net/10803/299210.
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In the Electromagnetic Compatibility research area, an unsolved interference problem is the measurement and evaluation of the distortion produced by radiated transient disturbances on digital communication systems. This impulsive noise, which is generated by switching devices or by sparks, is a broadband interference that covers the spectrum from DC to several hundreds of megahertz or some gigahertz. Additionally, this man-made noise is characterized by its short and random burst parameters, which make really challenging to measure it correctly. During the thesis, we have explained that impulsive noise is not properly measured and evaluated to prevent interference scenarios, when the EMC standard methodologies are applied. Detectors, such as the quasi-peak, frequency sweep measurements or signal-to-noise limiting evaluation described in the harmonized standards of the electromagnetic compatibility do not enable to determine beforehand the influence of transient interferences.
Our strategy to overcome the non-profit measurement has been to perform novel measurement and evaluation techniques beyond EMC standards. The measurement technique developed joins the capabilities of EMI receivers and oscilloscope instrumentations to capture accurately the radiated transient interference. To carry out the measurement, the input stage of the EMI receiver is used for filtering and pre-amplifying purposes, conducting the IF output towards the oscilloscope, which is used for triggering and storage. Furthermore, a final post-processing stage is needed to obtain in time-domain the in-phase and quadrature components of the transient interference.
Once the radiated transient interference has been measured properly, an accurate evaluation of the distortion produced to a digital communication system can be estimated. To evaluate the impact of the transient interference, a combination of the time-domain measurement with base-band simulation has been proposed to fulfil the thesis goal. The IQ time-domain measurement enables us to characterize the impulsive-noise present at the communication channel and determine the distortion produced to the digital communication system by means of base-band simulation. The procedure to determine the BER using the base-band simulation has been validated with experimental results, comparing the results reached with the developed methodology with the ones obtained when a communication system device is placed under radiated transient. Excellent results have been obtained employing the developed methodology, considering the interference produced by radiated transient to RFID or GSM communication systems
Additionally, a new measurement methodology to obtain the amplitude probability diagram (APD) has been developed, offering the possibility to determine the bit-error-rate including limit lines at the APD diagram. This measurement method, based on captures obtained from a general purpose oscilloscope, makes it possible to obtain the APD measurement at any frequency band with the same accuracy provided by an EMI receiver. Furthermore, the post-processing tools using mathematical software produce the APD results rapidly at any bandwidth, and this makes it more powerful than employing an EMI receiver.
The successful APD measurement system created is able to obtain the full-spectrum statistical measurement, employing several time-domain captures which can be acquired in practice immediately. In the final chapter of this thesis, the GSM system is interfered by radiated transients produced by sparks. The results provided by the APD diagram including the limit dots have been especially useful due to its fast capacity to interpret and quantify the degradation produced to the GSM system.En el camp de recerca de la compatibilitat electromagnètica, una de les problemàtiques no resoltes és la mesura i avaluació de les interferències produïdes per transitoris radiats sobre els equips de comunicació digitals. Aquest tipus de soroll impulsiu, que es genera per la commutació d' equips electrònics o guspires, és una interferència de banda ampla que ocupa l' espectre radioelèctric fins a diversos centenars de megahertz o algun gigahertz. A més, aquest soroll es caracteritza per la seva curta durada i l'aleatorietat dels seus paràmetres, i això fa que sigui molt complicat mesurar correctament la interferència. Al llarg de la tesi, hem explicat que el soroll impulsiu no es mesura ni s'avalua adequadament per evitar escenaris d'interferències si s'utilitzen les metodologies definides als estàndards d' EMC. Els detectors, com el de quasi-pic, l'escombratge en freqüència o l'avaluació basada en els límits relacionats amb la relació senyal a soroll no són vàlids per anticipar la influència de les interferències transitòries. La nostra estratègia per solucionar els problemes de les mesures normatives ha estat desenvolupar noves tècniques de mesura i avaluació fora dels estàndards d'EMC. La tècnica de mesura desenvolupada combina les capacitats dels receptors EMI i els oscil·loscopis per capturar la interferència transitòria radiada. Per realitzar les mesures, l'etapa d'entrada del receptor EMI s¿utilitza amb la finalitat de filtrar i preamplificar, enviant la sortida IF cap a l'oscil·loscopi, que es fa servir per detectar i emmagatzemar els transitoris. Per últim, en l'etapa de postprocessament, s'obtenen en el domini del temps els components en fase i en quadratura de la interferència transitòria. Una vegada s'ha mesurat adequadament la interferència radiada, es pot estimar correctament la distorsió produïda sobre els sistemes de comunicació digitals. Per avaluar l'impacte de la interferència transitòria i així complir amb l'objectiu de la tesi, s'ha proposat combinar les mesures en el domini del temps amb la simulació en banda base. La mesura IQ en el domini del temps ens permet caracteritzar el soroll impulsiu present al canal de comunicació i així determinar la distorsió produïda al sistema de comunicació digital mitjançant la simulació en banda base. El procediment per determinar el BER fent servir la simulació en banda base ha estat validat amb resultats experimentals, i s'han comparat els resultats obtinguts utilitzant la metodologia desenvolupada amb els resultats proporcionats directament col·locant un dispositiu sota la influència de transitoris radiats. Els excel¿lents resultats obtinguts considerant interferències produïdes sobre sistemes RFID i GSM han estat publicats. D'altra banda, també s'ha desenvolupat un nou mètode de mesura per adquirir el diagrama de probabilitat d¿amplitud (APD), oferint la possibilitat de determinar la probabilitat d'error en el bit incloent límits en el diagrama APD. Aquest mètode de mesura, basat en captures obtingudes mitjançant un oscil·loscopi de propòsit general, fa possible obtenir la mesura APD en qualsevol banda freqüencial amb la mateixa exactitud que proporciona un receptor EMI. A més, amb les eines de postprocessament desenvolupades és possible produir els resultats APD ràpidament i amb qualsevol amplada de banda, i això fa que sigui un mètode de mesura més potent que no pas utilitzar un receptor EMI. L'exitós sistema de mesura creat per obtenir l'APD és capaç d'obtenir la mesura estadística en tot l'espectre radiolèctric utilitzant poques captures en el domini del temps, les quals a la pràctica soón adquirides de forma inmediata. Al capítol final de la tesi, el sistema GMS és interferit per transistors radiats produïts per guspires. El resultat proporcionat pel diagrama APD, incloent-hi els límits, és especialment útil gràcies a la seva rapidesa per interpretar i quantificar la degradació produïda sobre el sistema GSM.
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Sandberg, Sara. "Modulation and channel effects in digital communication /." Luleå : Luleå University of Technology, 2005. http://epubl.luth.se/1402-1757/2005/49.
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Bradley, Martin James. "Adaptive equalisation for fading digital communication channels." Thesis, Durham University, 1996. http://etheses.dur.ac.uk/5177/.
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This thesis considers the design of new adaptive equalisers for fading digital communication channels. The role of equalisation is discussed in the context of the functions of a digital radio communication system and both conventional and more recent novel equaliser designs are described. The application of recurrent neural networks to the problem of equalisation is developed from a theoretical study of a single node structure to the design of multinode structures. These neural networks are shown to cancel intersymbol interference in a manner mimicking conventional techniques and simulations demonstrate their sensitivity to symbol estimation errors. In addition the error mechanisms of conventional maximum likelihood equalisers operating on rapidly time-varying channels are investigated and highlight the problems of channel estimation using delayed and often incorrect symbol estimates. The relative sensitivity of Bayesian equalisation techniques to errors in the channel estimate is studied and demonstrates that the structure's equalisation capability is also susceptible to such errors. Applications of multiple channel estimator methods are developed, leading to reduced complexity structures which trade performance for a smaller computational load. These novel structures are shown to provide an improvement over the conventional techniques, especially for rapidly time-varying channels, by reducing the time delay in the channel estimation process. Finally, the use of confidence measures of the equaliser's symbol estimates in order to improve channel estimation is studied and isolates the critical areas in the development of the technique — the production of reliable confidence measures by the equalisers and the statistics of symbol estimation error bursts.
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Jalali, Sammuel. "Wireless Channel Equalization in Digital Communication Systems." Scholarship @ Claremont, 2012. http://scholarship.claremont.edu/cgu_etd/42.
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Our modern society has transformed to an information-demanding system, seeking voice, video, and data in quantities that could not be imagined even a decade ago. The mobility of communicators has added more challenges. One of the new challenges is to conceive highly reliable and fast communication system unaffected by the problems caused in the multipath fading wireless channels. Our quest is to remove one of the obstacles in the way of achieving ultimately fast and reliable wireless digital communication, namely Inter-Symbol Interference (ISI), the intensity of which makes the channel noise inconsequential.
The theoretical background for wireless channels modeling and adaptive signal processing are covered in first two chapters of dissertation.
The approach of this thesis is not based on one methodology but several algorithms and configurations that are proposed and examined to fight the ISI problem. There are two main categories of channel equalization techniques, supervised (training) and blind unsupervised (blind) modes. We have studied the application of a new and specially modified neural network requiring very short training period for the proper channel equalization in supervised mode. The promising performance in the graphs for this network is presented in chapter 4.
For blind modes two distinctive methodologies are presented and studied. Chapter 3 covers the concept of multiple "cooperative" algorithms for the cases of two and three cooperative algorithms. The "select absolutely larger equalized signal" and "majority vote" methods have been used in 2-and 3-algoirithm systems respectively. Many of the demonstrated results are encouraging for further research.
Chapter 5 involves the application of general concept of simulated annealing in blind mode equalization. A limited strategy of constant annealing noise is experimented for testing the simple algorithms used in multiple systems. Convergence to local stationary points of the cost function in parameter space is clearly demonstrated and that justifies the use of additional noise. The capability of the adding the random noise to release the algorithm from the local traps is established in several cases.