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1
Ni, Chih-Hwa. "Signal Reception Via Multi-Platform Receivers". Thesis, Monterey, California. Naval Postgraduate School, 2012. http://hdl.handle.net/10945/17428.
Testo completoAbstract (sommario):
In this thesis a reference-based successive interference cancellation (RSIC) scheme is proposed for mitigating interference in multi-platform communications. The performances of two RSIC techniques (Non-Demodulated and Demodulated) for quadrature phase shift keying (QPSK) modulation in orthogonal frequency division multiplexing (OFDM) system are analyzed. Simulations show RSIC schemes give considerable increase in performance compared to a system where interference cancellation is not utilized.
2
Hamilton, Terry. "Upgrade of RCB Receivers for C-Band Reception". International Foundation for Telemetering, 2009. http://hdl.handle.net/10150/606035.
Testo completoAbstract (sommario):
ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, NevadaExisting telemetry ground receivers typically operate in a bandwidth between 215MHz to 2485MHz, while the new C-Band covers 4.4GHz to 5.15GHz. Additionally, some installations are choosing to incorporate down converters in the antenna as an alternate approach. This paper describes an innovative approach to solving all of these problems, by enhancing the capabilities of existing range assets. The plan is to upgrade existing fielded receivers without impacting their existing functionality to also include C-Band reception. The upgrade module along with the software revision will provide the user with a fully functional receiver in the existing bands and the newly added bands. This will be accomplished by the development of an advanced down converter sections with coverage across all bands that will replace existing modules within the telemetry receivers. It is the details of this development that will be presented.
3
Banciu, Marian Gabriel Electrical Engineering & Telecommunications Faculty of Engineering UNSW. "Radio frequency and microwave design methods for mobile communications". Awarded by:University of New South Wales. School of Electrical Engineering and Telecommunications, 2003. http://handle.unsw.edu.au/1959.4/18814.
Testo completoAbstract (sommario):
The Global System for Mobile communications (GSM), which covers 54% of the world's mobile market, evolved into the General Packet Radio Service (GPRS). The thesis addresses interference suppression using new radio frequency (RF) and microwave design methods for GSM and GPRS. The overall outcome is interference reduction and enhanced network capacity, leading to superior quality of service (QoS) for wider area coverage. The main results can be summarized as follows * Design, manufacturing and characterisation measurements of new compact filters for GSM and GPRS base stations in order to reduce the out-of-band interference. It is shown that filters with novel microstrip resonators - dual mode filters and cross coupled filters - provide both a high degree of miniaturisation and narrow bandwidth. * Development of a new 3-D Finite-Difference Time-Domain (FDTD) design method for new microstrip filters. A non-homogeneous Perfectly Matched Layer (NH-PML) was implemented for Absorbing Boundary Conditions (ABC) to increase the accuracy of the FDTD method. Signal estimation techniques were developed to speed up FDTD computations. A novel design method based on neural networks (NN) and FDTD was implemented to reduce the total design time. * Investigation of High Temperature Superconductors (HTS) thin film resonators and antennas at microwave frequencies. High Q-factor HTS devices considerably enhance both the front-ends sensitivity and selectivity of wireless receivers. * Design, manufacturing and testing of radio frequency (RF) electronics for 16 elements GSM and GPRS Smart Antenna for multipath fading mitigation and for in-band interference including co-channel interference (CCI) suppression.
4
Kellerman, Valpre Cecilia. "Modular approach to the development of a two-way radio receiver system". Thesis, Stellenbosch : University of Stellenbosch, 2004. http://hdl.handle.net/10019.1/16362.
Testo completoAbstract (sommario):
Thesis (MScIng)--University of Stellenbosch, 2004.ENGLISH ABSTRACT: The preliminary development of a FM radio receiver module is discussed. An existing narrowband system operating between 48MHz and 50MHz will be replaced. Digital components were investigated, compared and used with analogue techniques to build a more flexible two-way radio receiver system. A direct digital synthesizer was considered as a replacement for the current synthesized phased lock loop local oscillator and much attention was given to the local oscillator and mixer design, characteristics and measurement procedures. A detailed study of receiver systems was undertaken to determine the specifications needed for every receiver component to achieve satisfactory receiver performance in the end. Receiver characteristics as well as receiver measurement procedures are defined. A software tool was developed to aid the design process, establishing computationally whether the receiver specifications are met prior to the final design. The complete design process, from fundamental specifications through to the developed final receiver module is discussed. A modular design approach was used to guarantee easy manufacturing, substitution and testing. This approach comprises the break-down of the receiver into well defined components that are each matched to 50O. The separate components of the system were designed, measured and characterized to make it possible to replace only a single component instead of the entire system when a part becomes redundant.
AFRIKAANSE OPSOMMING: Die grondslag vir die ontwikkeling van ‘n FM radio ontvanger module word in hierdie dokument gelê. ‘n Bestaande noubandstelsel wat tussen 48MHz and 50MHz ontvang word vervang deur hierdie nuwe stelsel wat aangewend sal kan word in die bestaande tweerigtingradio se omhulsel. Digitale komponente is ondersoek, vergelyk en gebruik saam met analoogtegnieke om ‘n meer buigsame radiostelsel te bewerkstellig. ‘n Direkte digitale sintitiseerder is oorweeg as ‘n vervanging vir die huidige fasesluitlus ossillator met heelwat klem op die oscillator-en mengerontwerp, komponent spesifikasies en metingsprosedures. ‘n Diepgaande studie van ontvangerstelsels is gedoen om te bepaal wat die tipiese spesifikasies vir elke ontvangerstadium is, sodat die finale ontvanger se spesifikasies behaal kan word. Ontvanger eienskappe en meetprosedures word volledig gedefinieer. ‘n Sagtewareprogram is ontwikkel om die ontvanger-ontwerpsproses te vergemaklik deur vooraf te kan vasstel watter ontvangerspesifikasies bereik sal kan word al dan nie. Die volledige ontwerpsproses, vanaf fundamentele spesifikasies tot by die finale ontvanger word omskryf. ‘n Modulere-ontwerp prosedure is gebruik ter versekering van die maklike vervaardiging, vervanging en toetsing van elke komponent. Die radio is tydens ontwerp opgebreek in boublokkies wat elkeen aangepas word na 50O. Elke aparte boublokkie van die ontvangerstelsel is afsonderlik ontwerp, gemeet en volledig gespesifiseer om dit moontlik te maak om slegs een komponent te vervang in plaas van die hele stelsel wanneer ‘n enkele komponent nie meer beskikbaar is nie.
5
Green, David Robert. "M-Net decoder production : a technical analysis". Thesis, Cape Technikon, 1989. http://hdl.handle.net/20.500.11838/1130.
Testo completoAbstract (sommario):
Thesis (Masters Diploma (Technology))--Cape Technikon, Cape Town, 1989The document initially describes the operation of the decoder and the production system. Thereafter actual engineering problems are stated and their solutions discussed. The project involves the accurate identification of problem areas on the production line and the systematic solving for each case. Subjects include static electricity pretesting and automatic insertion machine defects. Analysis of these problems provides one with a better perspective towards the production line and its inherent problems. Results and solutions are presented photographically as well as tabulated in the annexure. In some cases, such as defect classification, deductions were concluded that were very different from those initially expected.
6
Tidwell, Steve Chase 1957. "DESIGN OF A 5X AFOCAL RELAY LENS FOR A HETERODYNE SYSTEM (LASER)". Thesis, The University of Arizona, 1986. http://hdl.handle.net/10150/291288.
Testo completo
7
Yeung, Kim-sang, e 楊儉生. "The design and multiplier-less realization of a novel digital IF for software radio receivers". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2003. http://hub.hku.hk/bib/B2946660X.
Testo completo
8
Nel, Christoffel Antonie. "The creation of nonlinear behavioral-level models for system level receiver simulation". Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/50128.
Testo completoAbstract (sommario):
Thesis (MScEng)--Stellenbosch University, 2004.ENGLISH ABSTRACT: The aim of this thesis was to investigate the use of behavioral level models in receiver simulations using the capabilities of Agilent's Advanced Design System. Behavioral level modeling has become increasingly attractive because it offers faster and easier results for system level simulations. The work in this thesis focused strongly on nonlinear measurements to characterize the various nonlinear phenomena that are present in amplifiers and mixers. Measurement automation software was developed to automate the process. An error correction technique was also developed to increase the accuracy of spectrum analyzer measurements. The measured data was used to implement the behavioral level amplifier and mixer models in ADS. The accuracy of the models was compared to measured data and the different available models were compared. Finally the models were combined to realize different receivers and were used to do typical receiver tests. These test include gain and gain compression, two-tone intermodulation and spurious responses. The results are compared to measured data to test the accuracy and usefulness of the models and simulation techniques.
AFRIKAANSE OPSOMMING: Die doel van hierdie tesis was om stelsel-vlak gedrags-modelle te ondersoek soos hulle in Agilent se Advanced Design System (ADS) aangebied word. Die modellering van die stelselvlak-gedrag van komponente en stelsels is aantreklik aangesien dit 'n hoë vlak beskrywing van komplekse kommunikasie stelsels moontlik maak. Akkurate stelsel-vlak simulasies sal lei tot vinnige ontwikkeling en evaluasie van nuwe sisteme. Die resultate wat verkry word is egter afhanklik van die beskikbaarheid van akkurate stelsel-vlak gedragsmodelle Die tesis het baie sterk op metings staat gemaak om die nie-liniêre gedrag van versterkers en mengers te karakteriseer. Meet sagteware is ontwikkel om die verskillende metings te automatiseer. Fout korreksie vir spetrum-analiseerder-metings is ook ontwikkel. Die gemete data is gebruik om die nie-liniêre gedrags-modelle in ADS te implementer. Die modelle is in simulasies gebruik en die akuraatheid van die simulasies is teen gemete data getoets. Die finale deel van die tesis gebruik die modelle om tipiese ontvanger karakteristieke te voorspel. Die volgende toetse is gedoen: aanwins en kompressie, twee-toon intermodulasie en hoer orde meng produkte. Die resultate van die toetse is met gemete data vergelyk om die akuraatehied en bruikbaarheid van die verskillende modelle te vergelyk.
9
Hawbaker, Dwayne Allen. "Indoor wide band radio wave propagation measurements and models at 1.3 ghz and 4.0 ghz". Thesis, Virginia Tech, 1991. http://hdl.handle.net/10919/44287.
Testo completoAbstract (sommario):
An extensive radio wave propagation measurement campaign was conducted at 1.3 GHz and 4.0 GHz inside four buildings, including a sports arena, a modern closed-plan office building, and two dissimilar, open-plan factories. Measurements were recorded at 57 locations using base station antenna heights of 1.7 meters and 4.0 meters. Results were obtained for mean and maximum excess delay, rms delay spread, time delay jitter, differential delay jitter, and path loss through analyses of impulse response estimates, which were obtained via repetitive 5 ns probing pulses. The effects of frequency, antenna height, topography (line-of-sight or obstructed direct path), and building environment on delay spread and path loss are quantified. Results indicate that, on average, the frequencies and antenna heights used in this study have minimal impact on rms delay spread and path loss. However, topography and building environment significantly affect these parameters. RMS delay spread values as high as 230 ns were observed in open plan factories. Computed path loss power law exponents are 1.84 and 2.35 for line-of-sight and obstructed topographies, respectively. A second campaign was conducted to determine the effects of antenna directivity and polarization on propagation parameters. On average, line-of-sight indoor channels offer 8 dB of cross-polarization discrimination, whereas obstructed environments offer less than 3 dB. Directional antennas provide a significant reduction in rms delay spread over omni-directional antennas. In line-of-sight environments, circular polarization provides an additional delay spread reduction.Master of Science
10
Schaubach, Kurt Richard. "Microcellular radio channel prediction using ray tracing". Thesis, This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-09122009-040308/.
Testo completo
11
Kunselman, Gary L. "Radio frequency power amplifiers for portable communication systems". Thesis, Virginia Tech, 1992. http://hdl.handle.net/10919/41493.
Testo completoAbstract (sommario):
Portable communication systems require, in part, high-efficiency radio frequency power amplifiers (RF PA) if battery lifetime is to be conserved. Conventional amplifier classifications and definitions are presented in a unified and concise format. The Bipolar Junction Transistor (BJT) and Metal-Semiconductor Field Effect Transistor (MESFET) are evaluated as active devices in high-efficiency RF PA designs. Two amplifier classes (class CE and class F) meet the system requirements of an 850 MHz operating frequency, a power output of 3 W, a battery supply voltage of 9 Vdc, and a sinusoidal-type signal to be amplified. Both classes are evaluated through recent research literature and simulated using the PSpice® computer simulation program. Class CE and class F are found to provide efficiencies exceeding 80 percent under the given system constraints.Master of Science
12
Tsui, Kai-man, e 徐啟民. "Efficient design and realization of digital IFs and time-interleaved analog-to-digital converters for software radio receivers". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B40987917.
Testo completo
13
Dubbert, Dale F. "The RMS phase error of a phase-locked loop FM demodulator for standard NTSC video". Thesis, Kansas State University, 1986. http://hdl.handle.net/2097/9911.
Testo completo
14
Arici, Tarik. "Single and multi-frame video quality enhancement". Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/29722.
Testo completoAbstract (sommario):
Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2009.Committee Chair: Yucel Altunbasak; Committee Member: Brani Vidakovic; Committee Member: Ghassan AlRegib; Committee Member: James Hamblen; Committee Member: Russ Mersereau. Part of the SMARTech Electronic Thesis and Dissertation Collection.
15
Gendron, Paul John. "A comparison of digital beacon receiver frequency estimators". Thesis, This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-09292009-020307/.
Testo completo
16
Schwartz, Danielle. "From turnstile to transmitter : John Vassos, industrial designer, 1927-1941". Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=85957.
Testo completoAbstract (sommario):
This study examines the birth of television and the modern media corporation that launched it, through the archives of the designer of the "first" set, John Vassos, a Greek-born American industrial designer, interior decorator, and illustrator (1898-1985). Vassos's early career is used as a case study to analyze the historical and cultural forces that shaped the emergence of this new media and the new profession of industrial design, through archival materials housed in the Archives of American Art at the Smithsonian Institution in Washington D.C. and at Syracuse University. Specifically, this thesis unites various parts of Vassos's early career, from his modernist illustrations to industrial design, through the aesthetics and practices of modernism. As RCA's lead industrial designer for over 40 years, Vassos was involved in the design and promotion of RCA's electronic products, including radios and televisions and studio equipment. Vassos also designed the new spaces carved out for their use in the home including the "living room of the future" featured at the 1939 World's Fair. Drawing from his skills as an illustrator, designer and display expert, Vassos helped develop RCA's public image at a time of its greatest expansion in radio and television manufacturing and broadcasting. This reading of Vassos's work is both diachronic, taking into account his work over the early part of his career to analyze his specific contribution and synchronic, in relationship to other designers working contemporaneously. Thus, this thesis explores Vassos's double role as a participant, with active agency within the emergence of the new field and as a subject, constrained by social roles and forces. Ranging from turnstile to the transmitter, Vassos along with other industrial designers used the streamlined aesthetic to create visual unity among mechanical and electronic products, from home to office, from subway to skyline.
17
Van, Den Biggelaar Olivier. "Distributed spectrum sensing and interference management for cognitive radios with low capacity control channels". Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209612.
Testo completoAbstract (sommario):
Cognitive radios have been proposed as a new technology to counteract the spectrum scarcity issue and increase the spectral efficiency. In cognitive radios, the sparse assigned frequency bands are opened to secondary users, provided that interference induced on the primary licensees is negligible. Cognitive radios are established in two steps: the radios firstly sense the available frequency bands by detecting the presence of primary users and secondly communicate using the bands that have been identified as not in use by the primary users.In this thesis we investigate how to improve the efficiency of cognitive radio networks when multiple cognitive radios cooperate to sense the spectrum or control their interferences. A major challenge in the design of cooperating devices lays in the need for exchange of information between these devices. Therefore, in this thesis we identify three specific types of control information exchange whose efficiency can be improved. Specifically, we first study how cognitive radios can efficiently exchange sensing information with a coordinator node when the reporting channels are noisy. Then, we propose distributed learning algorithms allowing to allocate the primary network sensing times and the secondary transmission powers within the secondary network. Both distributed allocation algorithms minimize the need for information exchange compared to centralized allocation algorithms.
Doctorat en Sciences de l'ingénieur
info:eu-repo/semantics/nonPublished
18
Sahu, Biranchinath. "Integrated, Dynamically Adaptive Supplies for Linear RF Power Amplifiers in Portable Applications". Diss., Georgia Institute of Technology, 2004. http://hdl.handle.net/1853/7607.
Testo completoAbstract (sommario):
Energy-efficient radio frequency (RF) power amplifiers (PAs) are critical and paramount to achieve longer battery life in state-of-the-art portable systems because they typically determine and dominate the power consumption of such devices. In this dissertation, a high-efficiency, linear RF PA with a dynamically adaptive supply and bias current control for code division multiple access (CDMA) and wideband CDMA (WCDMA) is conceived, simulated, and experimentally demonstrated with a discrete PCB-level design and in integrated circuit (IC) form. The PA efficiency is improved by dynamically adjusting both its supply voltage and bias current, there by minimizing its quiescent power dissipation. The PA supply voltage is derived from the battery by a noninverting, synchronous buck-boost switching regulator because of its flexible functionality and high efficiency. Adjusting the PA supply voltage and bias current by tracking the output power, instead of following the complete envelope in large baseband bandwidth wireless applications, is achieved by a converter with a lower switching frequency and consequently higher light-load efficiency, which translates to prolonged battery life.
A discrete PCB-level prototype of the proposed system with 915 MHz center frequency, CDMA IS-95 signal having 27-dBm peak-output power resulted in more than four times improvement in the average efficiency compared to a fixed-supply class-AB PA while meeting the required performance specifications. In the IC solution fabricated in AMIs 0.5-micron CMOS process through MOSIS, a dual-mode, buck-boost converter with pulse-width modulation (PWM) control for high power and pulse-frequency modulation (PFM) for low power is designed and implemented to improve the PA efficiency during active and standby operation, respectively. The performance of the dynamically adaptive supply and bias control IC was validated by realizing a 25-dBm, 1.96 GHz center frequency, WCDMA PA over an input supply range of 1.4 4.2 V. The PA with dual-mode power supply and bias control IC showed an average-efficiency improvement of seven times compared to a fixed-supply class-AB PA, which translates to five times improvement in battery life assuming the PA is active for 2 % of the total time and in standby mode otherwise.
19
Wei, James. "Techniques d'échantillonnage des signaux radio et évaluation des MEMS dans un récepteur multi mode reconfigurable". Lyon, INSA, 2008. https://theses.insa-lyon.fr/publication/2008ISAL0060/these.pdf.
Testo completoAbstract (sommario):
Dans les années à venir les systèmes de téléphonie de quatrième génération devront assurer une convergence des différents réseaux pour offrir une multitude de services et d'applications de façon transparente pour l'utilisateur. Cette convergence impose des contraintes sévères sur le développement des terminaux qui devront être multi-modes, multi-bandes et multi-standards. Une des solutions pour y parvenir est de développer des récepteurs de signaux RF dont la numérisation est réalisée le plus près possible de l'antenne. C'est une approche de la radio logicielle qui est particulièrement intéressante pour les opérateurs de télécommunication puisque les fonctions implémentées de façon digitale sont beaucoup plus adaptées à la reconfiguration que les fonctions analogiques. Le point clé de la numérisation réside dans l'échantillonnage du signal. Les dégradations apportées par cette étape (jitter, bande passante, non-linéarité) ne permettent pas actuellement de remplir les cahiers des charges des systèmes actuels. Dans ce contexte, l'objectif de cette thèse est donc d'étudier les différentes techniques d'échantillonnage des signaux radio dans un récepteur et d'analyser l'influence que pouvaient avoir les MEMS (MicroElectroMechanical System) sur l'architecture du terminal. Plus précisément, la solution de filtrage avec les filtres MEMS dans un récepteur échantillonné a été examinée par rapport à la solution actuelle de filtrage externe. Ces études ont également évalué les différentes solutions architecturales qui permettent de réduire les contraintes de l'échantillonneur. Cette première étape a permis d'établir une comparaison quantitative entre ces différentes solutions en termes du facteur de bruit et du besoin de filtrage et s'est conclue par l'identification d'une solution architecturale et par l'élaboration des cahiers des charges relatifs aux blocs critiques dans le récepteur. Afin de vérifier l'architecture proposée, un modèle de système a été développé et un prototype à signaux mixtes pour un filtre échantillonné à une fréquence intermédiaire élevée a été réalisé en technologie CMOS 65 nmThe future development of 4G system of wireless telephony must assure the compatibility of different networks and protocols in arder to offer users universal services and applications with seamless transitions. This compatibility imposes future terminais to be multi-mode, multi-ban and multi-standard. One solution being actively pursued at present is to develop a receiver which digitize signais as close to the antenna a possible. The approach, also known as Software Defined Radio (SOR), is particularly appealing to telephone operators given that it is much easier to reconfigure a network in a digital domain than in an analogue domain. The critical point in digitization rests in sampling. In reality the existing sampling techniques and receiver architectures do not yet suffice to overcome signal degradations of jitter, bandwidth and non linearity due to sampling at high RF frequencies. This research includes the study the RF architectures adapted to broadband communication systems and the evaluation of various architecture options which makes it possible to reduce the constraints of the sampler. In addition, the technology of MEMS (MicroEiectroMechanical System) potentially to be integrated in sampling receiver architecture is assessed. Ln particulier, the solution of MEMS filtering in a sampled recepteur is compared to the solution of off-chip filtering. To verify the proposed solution, a system level model is developed and a prototype of a high-IF, mixed signal sampling filter is implement~d in CMOS 65nm
20
Ni, Min. "Cooperative Distributed Transmission and Reception". Digital WPI, 2013. https://digitalcommons.wpi.edu/etd-dissertations/325.
Testo completoAbstract (sommario):
"
In telecommunications, a cooperative scheme refers to a method where two or more users share or combine their information in order to increase diversity gain or power gain. In contrast to conventional point-to-point communications, cooperative communications allow different users in a wireless network to share resources so that instead of maximizing the performance of its own link, each user collaborates with its neighbours to achieve an overall improvement in performance. In this dissertation, we consider different models for transmission and reception and explore cooperative techniques that increase the reliability and capacity gains in wireless networks, with consideration to practical issues such as channel estimation errors and backhaul constraints.
This dissertation considers the design and performance of cooperative communication techniques. Particularly, the first part of this dissertation focuses on the performance comparison between interference alignment and opportunistic transmission for a 3-user single-input single- output (SISO) interference channel in terms of average sum rate in the presence of channel estimation errors. In the case of interference alignment, channel estimation errors cause interference leakage which consequently results in a loss of achievable rate. In the case of opportunistic transmission, channel estimation errors result in a non-zero probability of incorrectly choosing the node with the best channel. The effect of these impairments is quantified in terms of the achievable average sum rate of these transmission techniques. Analysis and numerical examples show that SISO interference alignment can achieve better average sum rate with good channel estimates and at high SNR whereas opportunistic transmission provides better performance at low SNR and/or when the channel estimates are poor.
We next considers the problem of jointly decoding binary phase shift keyed (BPSK) messages from a single distant transmitter to a cooperative receive cluster connected by a local area network (LAN). An approximate distributed receive beamforming algorithm is proposed based on the exchange of coarsely- quantized observations among some or all of the nodes in the receive cluster. By taking into account the differences in channel quality across the receive cluster, the quantized information from other nodes in the receive cluster can be appropriately combined with locally unquantized information to form an approximation of the ideal receive beamformer decision statistic. The LAN throughput requirements of this technique are derived as a function of the number of participating nodes in the receive cluster, the forward link code rate, and the quantization parameters. Using information-theoretic analysis and simulations of an LDPC coded system in fading channels, numerical results show that the performance penalty (in terms of outage probability and block error rate) due to coarse quantization is small in the low SNR regimes enabled by cooperative distributed reception. An upper/lower bound approximation is derived based on a circle approximation in the channel magnitude domain which provides a pretty fast way to compute the outage probability performance for a system with arbitrary number of receivers at a given SNR.
In the final part of this dissertation, we discuss the distributed reception technique with higher- order modulation schemes in the forward link. The extension from BPSK to QPSK is straightforward and is studied in the second part of this dissertation. The extension to 8PSK, 4PAM and 16QAM forward links, however, is not trivial. For 8PSK, two techniques are proposed: pseudobeamforming and 3-bit belief combining where the first one is intuitive and turns out to be suboptimal,the latter is optimal in terms of outage probability performance. The idea of belief combining can be applied to the 4PAM and 16QAM and it is shown that better/finer quantizer design can further improve the block error rate performance. Information-theoretic analysis and numerical results are provided to show that significant reliability and SNR gains can be achieved by using the proposed schemes. "
21
Zhao, Qiang. "New Results on Selection Diversity over Fading Channels". Thesis, Virginia Tech, 2003. http://hdl.handle.net/10919/31363.
Testo completoAbstract (sommario):
This thesis develops a mathematical framework for analyzing the average bit error rate performance of five different selection diversity combining schemes over slow, frequency non-selective Rayleigh, Nakagami-m and Ricean fading channels. Aside from the classical selection diversity, generalized selection combining and the â maximum outputâ selection methods, two new selection rules based on choosing the branch providing the largest magnitude of log-likelihood ratio for binary phase shift keying signals (with and without phase compensation in the selection process) are also investigated. The proposed analytical framework is sufficiently general to study the effects of dissimilar fading parameter and unequal mean received signal strengths across the independent diversity paths. The effect of branch correlation on the performance of a dual-diversity system is also studied. The accuracies of our analytical expressions have been validated by extensive Monte-Carlo simulation runs. The proposed selection schemes based on the log-likelihood ratio are attractive in the design of low-complexity rake receivers for wideband CDMA and ultra wideband communication systems.Master of Science
22
Salazar, Garay Roberto Francisco. "Kosma Dual Channel Test Receiver". Tesis, Universidad de Chile, 2010. http://repositorio.uchile.cl/handle/2250/102332.
Testo completoAbstract (sommario):
Ha sido construido, instalado y usado el KOSMA dual channel Test Receiver (TRx) para
NANTEN2, un telescopio de 4 m ubicado en Pampa la Bola en el norte de Chile a 4865 m de
altitud. El TRx es un receptor heterodino de dos canales para observaciones simultáneas
en 490 GHz (612 µm) y 840 GHz (368 µm). Ambos canales están apuntados a la misma
posición en el espacio. El TRx fue operado durante 2 años para verificar el rendimiento del
telescopio y para explorar el cielo sur en el rango submilimétrico.
El TRx tiene dos características principales. La primera es su diseño óptico monolítico
y cuasi-monolítico, el cual evita completamente la necesidad de alineación óptica dentro
y fuera del criostato. La óptica contiene un divisor de haz, dos grillas polarizadoras, cinco
espejos elipsoidales y dos osciladores de estado sólido. La óptica es realizada utilizando
una maquina CNC de cinco ejes.
La segunda característica es el cancelador de vibraciones. Este cancelador crea
un colchón de aire, el cual cancela las perturbaciones mecánicas introducidas por el
desplazamiento de helio en la cabeza fría, específicamente para la unidad criogénica
SRDK-415 producida por la empresa Sumitomo Heavy Industries.
En la tesis se entrega una descripción de los receptores heterodinos, el diseño del
cancelador de vibraciones, el diseño de la óptica, el rendimiento del receptor, las primeras
observaciones astronómicas obtenidas con este nuevo instrumento con las que se validan
las hipótesis y finalmente se presentan las conclusiones.
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Toledo, Marina Madeira de. "Dramaturgia do aqui e agora: presen?a, recep??o e sentido no corpo do ator". Universidade Federal do Rio Grande do Norte, 2013. http://repositorio.ufrn.br:8080/jspui/handle/123456789/12455.
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Previous issue date: 2013-04-12Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior
The actor is an actor during all the phases of creation and development of his character. (S) He goes beyond the moment of interpreting. In this sense, in her (his) daily life, the actor may use her (his) potential to extract from reality the necessary elements for the work of creation. This is a theoretical research which focus on the concept of presence in the actor s work, stretching the concept beyond the scene, encompassing different components such as the body, the word, the silence, the technique and the acting as the actor s stance in regards to his own reality. The objective of such stance is to integrate him (her) self in the environment, balancing his (hers) inner life with the outside life flow. To reach this objective, the research drew theoretical resources from the concept of presence in the actor s work according to BROOK, BARBA, GROTOWSKI and MNOUCHKINE and the studies on reception theory in ISER, 1996; GUMBRECHT, 2010. Thus, the dialogue between reader and actor high lights both as receivers in this work. A practical description of a street theater Kamch?tka show, featured by the Kamch?tka Company is used as an example of the research on the presence. The elements localized in this show are: play, listening, word, silence, meaning, relationship with here and now and the effects of the said presence
O ator n?o ? ator somente no momento da cena, ? ator em todas as etapas de cria??o e desenvolvimento de seu objeto est?tico. Nesse sentido, em seu cotidiano o ator pode procurar utilizar suas potencialidades para captar e traduzir da realidade o material para seu trabalho criativo. Esta pesquisa possui car?ter te?rico e aborda o conceito de presen?a no trabalho do ator, colocando-o como conceito para al?m da cena, n?o isolado de outros componentes entre eles o corpo, a palavra, o sil?ncio, a t?cnica, a representa??o como uma postura do ator para com sua realidade, a fim de integrar-se ao meio ambiente que o cerca, equilibrando seu conte?do interior com o conte?do exterior. Para tanto, utiliza como aporte te?rico encenadores que abordam o conceito de presen?a no trabalho do ator (BROOK; BARBA; GROTOWSKI; MNOUCHKINE) e os estudos da teoria da recep??o (ISER, 1996; GUMBRECHT, 2010), tra?ando um paralelo dial?gico entre as fun??es de leitor e ator, apontando ambos como receptores. Como exemplo pr?tico do estudo sobre a presen?a, ? feita aqui uma descri??o do espet?culo de teatro de rua Kamch?tka, realizado pela Companhia Kamch?tka, localizando nesse espet?culo os elementos: jogo, escuta, palavra, sil?ncio, sentido, rela??o com o aqui e agora e efeitos de presen?a; citados ao longo da disserta??o
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Trader, Robert Joseph. "INSTRUCTIONAL COMMUNICATION MATTERS: A TEST OF KNOWLEDGE ACQUSITION THEORY (KAT) FROM A MESSAGE-ORIENTED RECEIVER PERSPECTIVE". UKnowledge, 2007. http://uknowledge.uky.edu/gradschool_diss/505.
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This dissertation encourages adoption of a message-oriented receiver perspective when developing new instructional communication theories and proposes a causal-process model derived from Knowledge Acquisition Theory to demonstrate how this perspective can be used to predict student cognitive learning outcomes. Three hypotheses are generated to test the propositions of the derived model. The first hypothesis seeks to determine which dimensions of instructional message clarity and course content relevance best predict student interactions with instructional content. The second hypothesis predicts that student self-reported knowledge gains are a function of student interactions with content. The third hypothesis predicts that a significant proportion of the variance in knowledge gains can be explained by the combination of message characteristics with student content interactions both in and outside the classroom. A cross-sectional survey research design was used to collect responses from undergraduate students at a large southern public research university (n=333). The hypotheses were tested using linear and hierarchical regression and results demonstrated statistical support for all three hypotheses. The first hypothesis revealed the dimensions of instructional message clarity and course content relevance that significantly predicted student interactions with content inside and outside of class. Support for the second hypothesis illustrated that both in class and out of class content interactions significantly predicted student self-reports of knowledge gains. Finally, hypothesis 3 tested the comprehensive causalprocess model derived from Knowledge Acquisition Theory. The derived model received strong support and ultimately accounted for 65% of the variance in student perceptions of knowledge gains. Student perceptions of knowledge gains increased when students perceived textbook messages as clear, course goals and expectations as clear, content as relevant to their own lives, and when students enacted knowledge acquisition behaviors outside of class. Surprisingly, in class content interaction, presentation clarity, and procedural clarity dropped out of the model. Implications and limitations of the present study are discussed, directions for future research are suggested, and a persuasive argument is presented for why instructional communication researchers should continue to develop a message effects research agenda supporting the development of strong instructional communication theories that produce practical results to inform educational practices.
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White, Emily Kathleen. "The Reception of David Mamet's "Oleanna": The Politics of Interpretation and Received Opinion". W&M ScholarWorks, 1997. https://scholarworks.wm.edu/etd/1539626119.
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Lam, Daniel-Hung, e Robert Moyes. "A UNIQUE "CARD-BASED" FM/PM/BPSK IF RECEIVE FOR SATELLITE DATA RECEPTION". International Foundation for Telemetering, 1994. http://hdl.handle.net/10150/608825.
Testo completoAbstract (sommario):
International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, CaliforniaThis paper discusses the design and performance of the FM/PM/BPSK "personal computer card-based" receiver. In PSK, a carrier recovery technique must be used for signal demodulation. Costas loop is a well known method and is the basis in the design of the BPSK demodulation. A new design approach employing digital Box Car arm filters is used to improve receiver performance and flexibility. Detail design and performance of the digital Costas loop will be explored in a later section. A classical technique is employed for Phase demodulation with the use of tracking Phase Lock Loop. Frequency demodulation is designed around a simple, single FM discriminator IC.
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Zorzi, Avendaño Pablo Ignacio. "Design and construction of an optical systems for a 31- 45 GHz radioastronomical receiver". Tesis, Universidad de Chile, 2013. http://www.repositorio.uchile.cl/handle/2250/113708.
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Doctor en Ingeniería EléctricaEl Atacama Large Millimeter/Submillimeter Array (ALMA) es el observatorio astronómico más grande jamás construido. Se encuentra en el llano de Chajnantor, a una altura de 5.000 metros sobre el nivel del mar en el norte de Chile. Consiste en un conjunto de 66 antenas capaces de detectar fuentes de señal muy débil que nos llegan desde el espacio más profundo. El instrumento de detección en cada antena consiste en 10 receptores heterodinos de doble polarización y de muy alta sensibilidad que cubren la gama de frecuencia entre 30 a 950 GHz. En particular, el receptor de la Banda-1 está diseñado para cubrir la ventana espectral 31 45 GHz. Esta banda dará ayuda a los astrónomos a traer nueva luz en estudios de Anisotropías en el fondo de radiación cósmica, alta resolución del efecto Sunyaev-Zel ' dovich, detectar imágenes de gas de clúster a diferentes redshifts, estudios de lentes gravitacionales y monitoreo y mapeo del medio interestelar frío a intermedio y alto corrimiento al rojo. El objetivo de esta tesis consiste en diseñar y construir un completo sistema óptico para un receptor prototipo de radio astronomía que trabaje entre los 30 a 45 GHz y que cumpla con las especificaciones de la Banda 1 de ALMA. El sistema óptico incluye una lente, una bocina y un transductor Orthomodal de polarizaciones. Cada uno de estos componentes de microondas fueron diseñadas utilizando modelos teóricos existentes y que son bien conocidos, y luego fueron optimizados utilizando un software comercial numérico muy avanzado. Una vez que se encontró el modelo deseado, el dispositivo fue construido y caracterizado. Cada uno de los tres dispositivos que fueron desarrollados y luego construidos en nuestro laboratorio, presenta excelentes prestaciones y de buen acuerdo entre las mediciones experimentales y simulaciones. Además, una parte importante de esta tesis estuvo muy involucrada en el desarrollo y la construcción de una cámara anecoica de campo cercana que fue utilizada para medir los patrones de radiación de la bocina y también del sistema integrado por la bocina y la lente. Los logros más importantes de esta tesis fueron dos. (i) el desarrollo de un diseño de bocina de tipo spline-line muy compacta y que genera patrones de radiación de muy alta calidad. (ii) un separador de polarización ortogonal de señales que es muy compacto y compatible con un gran ancho de banda.
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Brito, Filho Francisco de Assis. "VCO Banda Larga Integrado para Receptor a Cinco Portas". Universidade Federal do Rio Grande do Norte, 2009. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15300.
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Previous issue date: 2009-09-03Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
This work presents an wideband ring VCO for cognitive radio five-port based receivers. A three-stage differential topology using transmission gate was adopted in order to maintain wide and linear tuning range and a low phase-noise. Monte-Carlo analysis were performed for phase-shift response of individual stages, which is an important figure of merit in five-port works. It was observed a fairly linear correlation between control voltage and oscillation frequency in the range between 200 MHz and 1800 MHz. The VCO was preliminarily designed for IBM 130nm CMOS technology
Este trabalho apresenta um VCO anel banda-larga para ser utilizado em receptores para R?dio Cognitivo baseados no correlator a cinco portas. Uma arquitetura diferencial de tr?s est?gios com porta de transmiss?o ? utilizada como forma de manter uma sintonia linear em larga faixa de frequ?ncias, bem como, um baixo ru?do de fase. An?lises de Monte-Carlo foram feita para avaliar as varia??es de fase em cada est?gio, o que constitui uma figura de m?rito importante em receptores baseados no correlator de cinco portas. Observou-se correspond?ncia razoavelmente linear entre tens?o de controle e freq??ncia de oscila??o na faixa compreendida entre 200 MHz e 1800 MHz. O VCO foi preliminarmente projetado para tecnologia CMOS IBM de 130 nan?metros
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Salós, Andrés Carlos Daniel. "Integrity monitoring applied to the reception of GNSS signals in urban environments". Thesis, Toulouse, INPT, 2012. http://www.theses.fr/2012INPT0047/document.
Testo completoAbstract (sommario):
L’intégrité des signaux GNSS est définie comme la mesure de la confiance qui peut être placée dans l’exactitude des informations fournies par le système de navigation. Bien que le concept d’intégrité GNSS a été initialement développé dans le cadre de l’aviation civile comme une des exigences standardisées par l’Organisation de l’Aviation Civile Internationale (OACI) pour l’utilisation du GNSS dans les systèmes de Communication, Navigation, et Surveillance / Contrôle du Trafic Aérien (CNS/ATM), un large éventail d’applications non aéronautiques ont également besoin de navigation par satellite fiable avec un niveau d’intégrité garanti. Beaucoup de ces applications se situent en environnement urbain. Le contrôle d’intégrité GNSS est un élément clé des applications de sécurité de la vie (SoL), telle que l’aviation, et des applications exigeant une fiabilité critique comme le télépéage basé sur l’utilisation du GNSS, pour lesquels des erreurs de positionnement peuvent avoir des conséquences juridiques ou économiques. Chacune de ces applications a ses propres exigences et contraintes, de sorte que la technique de contrôle d’intégrité la plus appropriée varie d’une application à l’autre. Cette thèse traite des systèmes de télépéage utilisant GNSS en environnement urbain. Les systèmes de navigation par satellite sont l’une des technologies que l’UE recommande pour le Service Européen de Télépéage Electronique (EETS). Ils sont déjà en cours d’adoption: des systèmes de télépéage pour le transport poids lourd utilisant GPS comme technologie principale sont opérationnels en Allemagne et en Slovaquie, et un système similaire est envisagé en France à partir de 2013. À l’heure actuelle, le contrôle d’intégrité GPS s’appuie sur des systèmes d´augmentation (GBAS, SBAS, ABAS) conçus pour répondre aux exigences de l’OACI pour les opérations aviation civile. C´est la raison pour laquelle cette thèse débute par une présentation du concept d’intégrité en aviation civile afin de comprendre les performances et contraintes des systèmes hérités. La thèse se poursuit par une analyse approfondie des systèmes de télépéage et de navigation GNSS en milieu urbain qui permets de dériver les techniques de contrôle d’intégrité GNSS les plus adaptées. Les algorithmes autonomes de type RAIM ont été choisis en raison de leur souplesse et leur capacité d´adaptabilité aux environnements urbains. Par la suite, le modèle de mesure de pseudodistances est élaboré. Ce modèle traduit les imprécisions des modèles de correction des erreurs d’horloge et d’ephemeride, des retards ionosphériques et troposphériques, ainsi que le bruit thermique récepteur et les erreurs dues aux multitrajets. Les exigences d’intégrité GNSS pour l’application télépéage sont ensuite dérivées à partir de la relation entre les erreurs de positionnement et leur effets dans la facturation finale. Deux algorithmes RAIM sont alors proposés pour l’application péage routier. Le premier est l’algorithme basé sur les résidus de la solution des moindres carrés pondérés (RAIM WLSR), largement utilisé dans l’aviation civile. Seulement, un des principaux défis de l’utilisation des algorithmes RAIM classiques en milieux urbains est un taux élevé d’indisponibilité causé par la mauvaise géométrie entre le récepteur et les satellites. C’est pour cela que un nouvel algorithme RAIM est proposé. Cet algorithme, basé sur le RAIM WLSR, est conçu de sorte à maximiser l’occurrence de fournir un positionnement intègre dans un contexte télépéage. Les performances des deux algorithmes RAIM proposés et des systèmes de télépéage associés sont analysés par simulation dans différents environnements ruraux et urbains. Dans tous les cas, la disponibilité du nouvel RAIM est supérieure à celle du RAIM WLSRGlobal Navigation Satellite Systems (GNSS) integrity is defined as a measure of the trust that can be placed in the correctness of the information supplied by the navigation system. Although the concept of GNSS integrity has been originally developed in the civil aviation framework as part of the International Civil Aviation Organization (ICAO) requirements for using GNSS in the Communications, Navigation, and Surveillance / Air Traffic Management (CNS/ATM) system, a wide range of non-aviation applications need reliable GNSS navigation with integrity, many of them in urban environments. GNSS integrity monitoring is a key component in Safety of Life (SoL) applications such as aviation, and in the so-called liability critical applications like GNSS-based electronic toll collection, in which positioning errors may have negative legal or economic consequences. At present, GPS integrity monitoring relies on different augmentation systems (GBAS, SBAS, ABAS) that have been conceived to meet the ICAO requirements in civil aviation operations. For this reason, the use of integrity monitoring techniques and systems inherited from civil aviation in non-aviation applications needs to be analyzed, especially in urban environments, which are frequently more challenging than typical aviation environments. Each application has its own requirements and constraints, so the most suitable integrity monitoring technique varies from one application to another. This work focuses on Electronic Toll Collection (ETC) systems based on GNSS in urban environments. Satellite navigation is one of the technologies the directive 2004/52/EC recommends for the European Electronic Toll Service (EETS), and it is already being adopted: toll systems for freight transport that use GPS as primary technology are operational in Germany and Slovakia, and France envisages to establish a similar system from 2013. This dissertation begins presenting first the concept of integrity in civil aviation in order to understand the objectives and constraints of existing GNSS integrity monitoring systems. A thorough analysis of GNSS-based ETC systems and of GNSS navigation in urban environments is done afterwards with the aim of identifying the most suitable road toll schemes, GNSS receiver configurations and integrity monitoring mechanisms. Receiver autonomous integrity monitoring (RAIM) is chosen among other integrity monitoring systems due to its design flexibility and adaptability to urban environments. A nominal pseudorange measurement model suitable for integrity-driven applications in urban environments has been calculated dividing the total pseudorange error into five independent error sources which can be modelled independently: broadcasted satellite clock corrections and ephemeris errors, ionospheric delay, tropospheric delay, receiver thermal noise (plus interferences) and multipath. In this work the fault model that includes all non-nominal errors consists only of major service failures. Afterwards, the GNSS integrity requirements are derived from the relationship between positioning failures and toll charging errors. Two RAIM algorithms are studied. The first of them is the Weighted Least Squares Residual (WLSR) RAIM, widely used in civil aviation and usually set as the reference against which other RAIM techniques are compared. One of the main challenges of RAIM algorithms in urban environments is the high unavailability rate because of the bad user/satellite geometry. For this reason a new RAIM based on the WLSR is proposed, with the objective of providing a trade-off between the false alarm probability and the RAIM availability in order to maximize the probability that the RAIM declares valid a fault-free position. Finally, simulations have been carried out to study the performance of the different RAIM and ETC systems in rural and urban environments. In all cases, the availability obtained with the novel RAIM improve those of the standard WLSR RAIM
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Lukasik, Stéphanie. "La reformulation de la figure du leader d'opinion au prisme de la réception de l'information des jeunes adultes via les réseaux socionumériques". Electronic Thesis or Diss., Aix-Marseille, 2021. http://www.theses.fr/2021AIXM0124.
Testo completoAbstract (sommario):
Les réseaux socionumériques ont partie liée avec l’activité de l’usager-récepteur théorisée par l’école de Columbia. Le lien entre système médiatique et système social qu’avait anticipé l’école de Columbia semble d’autant plus d’actualité avec la prise d’informations via les réseaux socionumériques. Désormais, les médias doivent compter avec les réseaux socionumériques et par conséquent avec les usagers-récepteurs. Par son partage d’information, chaque usager-récepteur peut devenir leader d’opinion à court terme. L’acte ponctuel de partage concrétise ce nouveau filtrage qui symbolise le passage au deuxième étage de la communication. Le partage est ainsi la réification conjoncturelle de l’influence personnelle qui transforme l’usager-récepteur en leader d’opinion. Dans ce modèle de l’usager-récepteur 2.0 du nouvel écosystème médiatico-socionumérique, les leaders d’opinion 2.0 sont assimilables à des partageurs d’opinion. Nous souhaitons montrer la pertinence d’un cadre théorique canonique pour l’analyse des usages et pratiques des réseaux socionumériques. Nous nous intéressons à ce que les « vrais gens de la vie quotidienne » choisissent et font des médias sur les réseaux socionumériques, à l’instar de l’école de Columbia qui s’intéressait au choix des gens et notamment à ce que les gens faisaient des médias traditionnels. L’objectif de cette recherche est de transposer ce modèle de Columbia au contexte des réseaux socionumériques afin de l’actualiser et de redéfinir, en son sein, la notion de leader d’opinion dont l’acception a été altérée. Notre apport est donc celui d’une analyse sociale de la communication humaine de l’information via les réseaux socionumériquesSocial-digital networks are linked to the user-receiver activity theorized by the Columbia school. The link between the media system and the social system that the Columbia school anticipated seems all the more relevant with the collect of information via social networks. Henceforth, the media must reckon with social networks and consequently with users-receivers. By sharing information, each user-receiver can become a short-term opinion leader. The one-off act of sharing materializes this new filter which symbolizes the passage to the second step flow of communication. Sharing is therefore the circumstantial reification of personal influence which transforms the user-receiver into an opinion leader. In this 2.0 user-receiver model of the new media digital-social networks ecosystem, 2.0 opinion leaders can be compared to opinion sharers. In order to understand the situations of opinion influence at work in circulation and reception activities, the information filter processes will be studied by taking up the structural elements of the model proposed by the Columbia school. We are interested in what "real people of everyday life" choose and do with media on social-digital networks, like the Columbia school which was interested in the people's choice and in particular in the part played by people in the flow of mass communications. The objective of this research is thus to transpose this Columbia model to the context of social-digital networks in order to update it and redefine, within it, the notion of opinion leader whose acceptance has been altered.Our contribution is therefore that of a social analysis of human communication of information via social-digital networks
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Maria, Andrea Gutierrez. "Papel do receptor B1 de cininas no desenvolvimento de melanoma murino". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/17/17131/tde-06012016-162046/.
Testo completoAbstract (sommario):
O melanoma malígno está entre os cânceres que mais têm aumentado nas últimas décadas representando um grande desafio terapêutico. Quando diagnosticado precocemente, as chances de cura por excisão cirúrgica com margens de segurança adequadas são altas. Entretanto, casos avançados de melanoma são resistentes às formas atuais de terapia; assim, um dos maiores desafios para a pesquisa em melanoma é a identificação de alvos moleculares para o desenvolvimento de novas estratégias de tratamento. A capacidade de impedir o desenvolvimento de um tumor depende do melhor entendimento das vias celulares e moleculares que operam no microambiente tumoral. Uma inflamação crônica e persistente contribui para o desenvolvimento do câncer, e mesmo tumores que não são epidemiologicamente ligados a patógenos, são caracterizados pela presença de componentes inflamatórios em seu microambiente. O Sistema Calicreínas-Cininas (SCC) é responsável por uma série de efeitos biológicos, como vasodilatação, modulação da dor e inflamação, contração/relaxamento da musculatura lisa e efeitos sobre a proliferação celular. A participação do receptor B1 de cininas é bem relacionada a processos inflamatórios; contudo, a relação entre o SCC e câncer ainda é pouco descrita na literatura. Com relação ao melanoma, não existem na literatura, estudos que relacionam a participação do SCC e essa patologia. Portanto, a identificação de mecanismos genéticos e de vias de sinalização que levam à formação e progressão tumoral é de extrema importância para um desenho racional de terapias. Assim, o objetivo desse trabalho foi estudar a participação do receptor B1 de cininas no desenvolvimento de melanoma. Primeiramente realizou-se ensaios in vitro com células de melanoma murino, B16F10, verificando-se a presença dos componentes do SCC nesta linhagem celular, bem como a capacidade de migração das células quando estimuladas com o agonista e antagonista do receptor B1. Posteriormente, induziu-se melanoma em animais selvagens e knockout para o receptor B1 e verificou-se expressão de citocinas, vias de proliferação e apoptose e vascularização nesses tumores a partir técnicas de PCR, western blotting e análise histológica. Observou-se que células B16F10 estimuladas com o agonista do receptor B1, diminuem a capacidade de migração. Tumores desenvolvidos em animais knockout para o receptor B1, possuem uma menor expressão gênica desse receptor quando comparados com tumores desenvolvidos em animais selvagens e apresentam vias de proliferação celular mais ativadas, além de uma vascularização irregular. Considerando esses resultados, sugerimos que o receptor B1 de cininas contribui para o impedimento da progressão tumoral, podendo, futuramente, ser um alvo terapêutico para o tratamento de melanoma.Malignant melanoma is between the cancer types that most have been increased in the last decades, representing a therapeutic challenge. When it is early detected, chances of cure through surgical excisions with secure margins are high. However, advanced cases of melanoma are resistant to all types of therapies; thus, one of the most challenges for research in melanoma is the identification of molecular targets to further develop new strategies of treatment. The ability to blockade the development of a tumor depends on a better understanding of cellular and molecular pathways that operate in the tumor microenvironment. A chronic and persistent inflammation contributes to cancer development, and, even tumors that are not epidemiologically linked to pathogens present inflammatory components in their microenvironment. The Kallicrein-Kinin System (KKS) is responsible for several biological effects, like, vasodilatation, modulation of pain and inflammation, contraction/relaxation of smooth muscles and cell proliferation. The kinin B1 receptor is well related to inflammatory processes, however, the involvement of the KKS in cancer development is, yet, not well described in the literature. Regarding to melanoma, studies relating the involvement of the KKS in melanoma development is still not available. This way, identification of genetic mechanisms and signaling pathways that drive melanoma formation and progression is extremely important for designing rational therapies in the future. Thus, the aim of this study was evaluate the participation of the kinin B1 receptor in melanoma progression. First, in vitro assays with murine melanoma cells, B16F10, were performed to verify the presence of the KKS components in this cell lineage, as well as the capacity of migration when these cells are stimulated with the B1 receptor agonist and antagonist. Then, melanoma was induced in wild type and B1 receptor knockout mice and the expression of cytokines, proliferation and apoptosis pathways and vascularization were studied by PCR, western blotting and histological analyses. We observed that B16F10 cells stimulated with the B1 receptor agonist had their capacity of migration decreased. Tumors developed in B1 receptor knockout mice showed a lower expression of this gene comparing to the tumors developed in wild type animals, also presenting higher activation of proliferation pathways and abnormal vessels. Considering these results, we suggest that the kinin B1 receptor contributes to blockade, at least in part, the tumor progression which can, in the future, become a therapeutic target for melanoma treatment.
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Nigro, Luciano Giannecchini. "Concepção de um receptor de cavidade para concentração de energia solar para aplicação em reatores químicos". Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/3/3150/tde-14072016-104455/.
Testo completoAbstract (sommario):
Este trabalho dimensionou um receptor de cavidade para uso como reator químico de um ciclo de conversão de energia solar para energia química. O vetor energético proposto é o hidrogênio. Isso implica que a energia solar é concentrada em um dispositivo que absorve a radiação térmica e a transforma em energia térmica para ativar uma reação química endotérmica. Essa reação transforma o calor útil em gás hidrogênio, que por sua vez pode ser utilizado posteriormente para geração de outras formas de energia. O primeiro passo foi levantar os pares metal/óxido estudados na literatura, cuja finalidade é ativar um ciclo termoquímico que possibilite produção de hidrogênio. Esses pares foram comparados com base em quatro parâmetros, cuja importância determina o dimensionamento de um receptor de cavidade. São eles: temperatura da reação; estado físico de reagentes e produtos; desgaste do material em ciclos; taxa de reação de hidrólise e outros aspectos. O par escolhido com a melhor avaliação no conjunto dos parâmetros foi o tungstênio e o trióxido de tungstênio (W/WO3). Com base na literatura, foi determinado um reator padrão, cujas características foram analisadas e suas consequências no funcionamento do receptor de cavidade. Com essa análise, determinaram-se os principais parâmetros de projeto, ou seja, a abertura da cavidade, a transmissividade da janela, e as dimensões da cavidade. Com base nos resultados anteriores, estabeleceu-se um modelo de dimensionamento do sistema de conversão de energia solar em energia útil para um processo químico. Ao se analisar um perfil de concentração de energia solar, calculou-se as eficiências de absorção e de perdas do receptor, em função da área de abertura de um campo de coleta de energia solar e da radiação solar disponível. Esse método pode ser empregado em conjunto com metodologias consagradas e dados de previsão de disponibilidade solar para estudos de concentradores de sistemas de produção de hidrogênio a partir de ciclos termoquímicos.This work aimed to design a cavity receptor for purpose of chemical reactor for cycles of energy conversion of solar energy to chemical energy. The proposed chemical agent is hydrogen gas. Solar energy is concentrated in a device that absorbs thermal radiation, transforming it in thermal energy, used to activate chemical reactions. This reaction transforms the heat in hydrogen gas and the last, in its turn, can be used to generate other forms of energy. The first step oh this work was an assessment of metal/oxides pairs studied in literature, which can be used to activate thermochemical cycles for hydrogen production. These pairs were compared based in four parameters, important to cavity receptor design: reaction temperature, physical state of the reactants and products, material resistance to several cycles; hydrolysis reaction rate and other aspects. The chosen pair, rated as the higher average in all parameters, was the pair tungsten and tungsten trioxide. (W/WO3). Based in the literature, it was determined a standard reactor, which was studied regarding cavity reactor performance. By such analysis, it was possible to determine the main design parameters, therefore, cavity aperture, window transmissivity, and the cavity geometric dimensions. The results allowed to establish a mathematical model in which solar energy can be converted in useful energy for chemical processes, inside a cavity receptor. Given a profile of solar energy concentration, it was calculated absorption and energy lost efficiencies, related to a solar concentration field and radiation available. This method can be used in tandem with available methodologies and data of solar predictions for hydrogen production by concentration systems via thermochemical cycles.
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RODRIGUES, Rosana Araújo. "O Lugar Da Música Uma Análise Do Processo Criativo Sob a Perspectiva Do Receptor". Universidade Federal de Goiás, 2010. http://repositorio.bc.ufg.br/tede/handle/tde/2726.
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Previous issue date: 2010-03-11This study aims the analysis of the productive process in music considering the optics of the receiver. This analysis focuses on the history of the occidental music guided by the aesthetic theory of the perception, its conclusions and projections in the musical field. It is the analysis of the relationship between the receiver and the formal space where the music takes place in the actual and metaphoric sense in the contingencies and circumstances that surround the act of surfacing. The objective is the search of an up to date vision about the musical reception beyond the simple sensorial perception. In the process, there is a discussion about the places of music production and reception, the concepts of perception, musical linguistics, and its ways of been learned. Also, there is a debate about the process of musical structure considering the perspective and aesthetical linked to the soundscape and acoustic.
Com foco na história da música ocidental e norteado pelas teorias da estética da recepção, suas inferências e projeções no campo musical, este estudo visa investigar o processo produtivo em música sob a ótica do receptor. Trata-se de uma análise da relação do receptor com os espaços formais de realização da música no sentido tanto concreto quanto metafórico nas contingências e circunstâncias que o cercam e conformam o ato da fruição. O objetivo é buscar uma visão atualizada da recepção musical que ultrapasse a questão da pura percepção sensorial. Discutem-se, portanto, ao longo da história da música ocidental, além dos lugares de produção e recepção da música, os conceitos de sentido, lingüisticidade musical e seus modos de apreensão, bem como os processos de estruturação musical numa perspectiva e estética vinculadas à acústica e à paisagem sonora.
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Ochoa, Castillo Sergio Pablo. "Diseño de un amplificador limitador cmos para velocidades en tecnologías submicrónicas". Bachelor's thesis, Universidad Ricardo Palma, 2018. http://cybertesis.urp.edu.pe/handle/urp/1356.
Testo completoAbstract (sommario):
Este informe técnico propone el diseño de un bloque llamado Amplificador Limitador que se encuentra en los equipos que trabajan con fibra óptica o con altas tasas de transmision de datos y que estan integrados en una pastilla de silicio. El objetivo principal es aumentar el ancho de banda de un Amplificador Limitador mediante la aplicación de la técnica Inductive Peaking para lograr velocidades que corresponden a una portadora óptica OC-192 equivalente a 10 Gbps bajo el estándar SONET. Haciendo uso de tecnología CMOS con transistores de 130 nm de ancho de canal.
A su vez se propone disminuir el consumo de potencia y el área ocupada en la pastilla de Silicio utilizando inductores activos y la eliminación de los capacitores de desacople DC entre etapas.
Los resultados finales Post Layout demuestran que es posible extender el ancho de banda con las técnicas mencionadas anteriormente, reducir el consumo total y el área ocupada en la pastilla de Silicio y cumplir con las especificaciones técnicas requeridas.
This technical report proposes the design of a block called Limiting Amplifier which is found in equipment that works with optical fiber or with high rates of data transmission and that are integrated in a silicon wafer. The main objective is to increase the bandwidth of a limiter amplifier by applying the Inductive Peaking technique to achieve speeds that correspond to an OC-192 optical carrier equivalent to 10 Gbps under the SONET standard, making use of CMOS technology with 130 nm channel width transistors.
At the same time, it is proposed to reduce the power consumption and the area occupied in the chip using active inductors and the elimination of DC decoupling capacitors between stages.
The final results of Post Layout show that it is possible to extend the bandwidth with the techniques mentioned above, reducing the total consumption and the area occupied in the silicon pellet and accomplishing with the required technical specifications.
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Bauer, Zachary Obenour. "A Calibration Method for a Controlled Reception Pattern Antenna and Software Defined Radio Configuration". Ohio University / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1357402542.
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Lind, Patrik. "Empty employment offices or empty apartments? : A study of the driving forces behind Swedish municipalities’ willingness to sign contracts with the Swedish central government regarding refugee reception". Thesis, Uppsala universitet, Nationalekonomiska institutionen, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-156557.
Testo completoAbstract (sommario):
The aim of Sweden’s refugee settlement policy is that refugees should be offered an initial place of dwelling in a municipality with available accommodation and a good labour market within commuting distance. Refugees risk long-run unemployment, if initially placed in a municipality with bad labour market opportunities (see Edin et al., 2004 and Åslund et al., 2006). It is therefore important to know to what extent the state of a municipality’s labour market (and not only availability of apartments) drives the willingness to receive refugees. No such study has previously been con- ducted. This paper thus aims to bridge this gap in the research by analyzing data between 2006-2010 for all 290 Swedish municipalities and their contracts with the Swedish central government regarding refugee reception. The main findings are, when accounting for municipality-fixed effects, that neither unemployment nor available apartments affect the probability of signing a contract. Additional govern- ment grants, on the other hand, has a positive effect on the likelihood of signing a contract. Among municipalities which do sign contracts, the agreed number of refu- gees is negatively affected by higher municipality unemployment and positively affected by additional available apartments.
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Thiebaut, Matthieu Jacques Andre. "Receptor super-regenetativo (900 MHz) implementado em tecnologia CMOS 0,35 'mu'm". [s.n.], 2006. http://repositorio.unicamp.br/jspui/handle/REPOSIP/262030.
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Orientador: Carlos Alberto dos Reis FilhoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação
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Resumo: O objetivo deste trabalho é propor uma topologia de receptor adequada para atender as exigências de uma rede de sensores sem fio, onde baixo consumo e baixo custo de fabricação são fundamentais.A topologia escolhida foi a do receptor super-regenerativo realizado em tecnologia CMOS 0,35Km e operando em 900 MHz. O chip foi montado e testado numa placa de alumina junto com alguns componentes passivos externos (circuito tanque e adaptação de impedância) necessários para seu funcionamento. Uma sensibilidade de -82 dBm para uma taxa de erro binário (BER) inferior a 0,1% foi obtida com um sinal modulado tudo-ou-nada (On-Off keying, OOK) de 64 kbits/s. O consumo deste receptor foi de 2,5 mW para uma tensão de alimentação de 2V.
Abstract: The purpose of this work is to develop a radio receiver, which is suitable for application in wireless sensor networks. Among the essential requirements for one such radio are included low power, low cost and high sensitivity. The topology of a super-regenerative receiver to operate in 900MHz was chosen, since it complies with all these requirements in addition to being appropriate for integration. Samples of the developed radio receiver were fabricated in 0,35Km CMOS technology. Prototypes were assembled on alumina plate using a few additional external components as an alternative to evaluate the performance of the radio without being affected by the low quality of the passives L and C used in the tuning block (tank and matching circuit). Test results have shown that the developed receiver features sensitivity of -82 dBm for a bit error rate (BER) lower than 0,1% with an On-Off Keying modulated signal of 64 kbit/s. Measure power consumption has been 2,5 mW for a supply voltage of 2 V.
Mestrado
Eletrônica, Microeletrônica e Optoeletrônica
Mestre em Engenharia Elétrica
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Souza, Fábio Gomes de. "Proposição de um simulador ginga-ncl para dispositivos portáteis". Universidade Federal do Amazonas, 2012. http://tede.ufam.edu.br/handle/tede/3289.
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Previous issue date: 2012-01-11The development of interactive content for digital TV systems involves a process that requires the use of several tools, among which stand out tools for editing, multiplexing, and presenting interactive content. When developing interactive applications for portable devices, such as cell phones, it is important to consider unique characteristics of those presentation environments, which may vary between different screen sizes, different data input mechanisms, support for interactive channel, among others. The research conducted in this study focused on presentation environments for interactive applications designed to run on portable receivers in accordance with the Brazilian Digital TV System. The proposed simulator, Simulador Ginga-NCL para Dispositivos Portáteis (SGDP) -- Ginga-NCL Simulator for Handhelds Devices -- includes essential features necessary for simulating a interactive application presentation environment. Tuning oneseg TV signal, extraction of interactive content from transport stream, Lua scripts interpretation, and NCL applications presentation control, are examples of essential features contemplated by SGDP. Additionally, the proposed simulator logs information about the processing and presentation of interactive content for further analysis by developers. The Symbian platform was chosen for implementation of SGDP, and systemic tests were performed to validate the tool.
O desenvolvimento de conteúdo interativo para sistemas de TV digital envolve um processo que requer o uso de diversas ferramentas; dentre as quais se destacam: ferramentas de edição, multiplexação, e apresentação de conteúdo interativo. Ao desenvolver aplicações interativas destinadas a dispositivos portáteis, tais como telefones celulares, é importante levar em consideração características particulares destes ambientes de apresentação, as quais podem variar entre dimensões de telas distintas, mecanismos de entrada de dados no sistema, suporte a canal de interatividade, dentre outros. A pesquisa realizada neste trabalho concentrou-se em ambientes de apresentação de aplicações interativas destinadas a receptores portáteis em conformidade com o Sistema Brasileiro de TV Digital. O simulador proposto, Simulador Ginga-NCL para Dispositivos Portáteis (SGDP), contempla funcionalidades essenciais, necessárias para simulação de um ambiente de apresentação de aplicações interativas. Sintonia do sinal de TV oneseg, extração de conteúdos interativos do fluxo de transporte, interpretação de scripts Lua, e controle de apresentação de aplicações NCL, são exemplos de funcionalidades essenciais contempladas pelo SGDP. Adicionalmente, o simulador proposto registra informações sobre o processamento, e apresentação, de conteúdos interativos para análise posterior por desenvolvedores. A plataforma Symbian foi escolhida para implantação do SGDP, e testes sistêmicos foram realizados para validação da ferramenta.
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Smith, Kristen A. "The Receptive and Expressive Language Outcomes of Children who have Received Cochlear Implants and have an Autism Spectrum Disorder". University of Cincinnati / OhioLINK, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1212095057.
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Pinto, Luiz Filipe da Silva Souza. "SMS como canal de interatividade para dispositivos portáteis". Universidade Federal do Amazonas, 2012. http://tede.ufam.edu.br/handle/tede/4470.
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Não Informada
Digital TV is increasingly present in the lives of Brazilians, because year after year, a large number of people are migrating from analog to digital as the analog system has a date for its shutdown. With the advancement of digital TV, you may notice significant improvements in audio and video technology used, it is also possible to establish an interaction between the viewer and the TV receiver device. In Brazil, this interaction occurs through the Ginga middleware technology developed by Brazilian researchers to standardize the interactive content sent to devices able to interpret it. In addition to televisions, another popular device is the mobile phone, which is present in a significant way across the country. The technology adopted by Brazil for the digital transmission of television signals, allows the phone to receive programming dedicated to portable devices in open and free way. The phone has a certain advantage over television due to its connectivity. Once the mobile phone is on most of the time connected to a telephone network, and may be 2G, 2.5G, 3G and 4G in the near future, while the television set is for the most part of the time offline (disconnected). This work presents a proposal to use the SMS service as interactive channel, also known as the return channel, for portable reception. This service is present in all mobile phones, and therefore may contribute to the popularization of the use of digital TV technology in the country.
A TV digital está cada vez mais presente na vida dos brasileiros, pois ano após ano, um número grande de pessoas está migrando do sistema analógico para o digital, uma vez que o sistema analógico tem data certa para seu encerramento. Com o avanço da TV digital, é possível notar melhoras significativas nas tecnologias de áudio e vídeo usadas, como também é possível estabelecer uma interação entre o telespectador e o dispositivo receptor. No Brasil, tal interação ocorre através do middleware Ginga, tecnologia desenvolvida por pesquisadores brasileiros para padronizar o conteúdo interativo enviado aos dispositivos capazes de interpretá-lo. Além dos televisores, outro dispositivo bastante popular é o telefone celular, que está presente de forma expressiva ao longo do país. A tecnologia adotada pelo Brasil para transmissão digital do sinal de TV, permite que o telefone celular receba a programação dedicada a dispositivos portáteis de formaaberta e gratuita. O telefone celular possui uma certa vantagem em relação ao aparelho de televisão no quesito conectividade. Uma vez que o telefone celular está na maior parte do tempo conectado a uma rede de telefonia, podendo ser 2G, 2.5G, 3G e em um futuro próximo 4G, enquanto que o aparelho de televisão está em sua maior parte do tempo offline (desconectado). Este trabalho apresenta uma proposta para o uso do serviço de SMS como canal de interatividade, também conhecido como canal de retorno, para recepção portátil. Este serviço está presente em todos os telefones celulares, e por isso, pode contribuir para a popularização do uso da tecnologia de TV digital no país.
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Albuquerque, Glauberto Leilson Alves de. "Constru??o e valida??o de um receptor GPS para uso espacial". Universidade Federal do Rio Grande do Norte, 2009. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15303.
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Previous issue date: 2009-11-20Global Positioning System, or simply GPS, it is a radionavigation system developed by United States for military applications, but it becames very useful for civilian using. In the last decades Brazil has developed sounding rockets and today many projects to build micro and nanosatellites has appeared. This kind of vehicles named spacecrafts or high dynamic vehicles, can use GPS for its autonome location and trajectories controls. Despite of a huge number of GPS receivers available for civilian applications, they cannot used in high dynamic vehicles due environmental issues (vibrations, temperatures, etc.) or imposed dynamic working limits. Only a few nations have the technology to build GPS receivers for spacecrafts or high dynamic vehicles is available and they imposes rules who difficult the access to this receivers. This project intends to build a GPS receiver, to install them in a payload of a sounding rocket and data collecting to verify its correct operation when at the flight conditions. The inner software to this receiver was available in source code and it was tested in a software development platform named GPS Architect. Many organizations cooperated to support this project: AEB, UFRN, IAE, INPE e CLBI. After many phases: defining working conditions, choice and searching electronic, the making of the printed boards, assembling and assembling tests; the receiver was installed in a VS30 sounding rocket launched at Centro de Lan?amento da Barreira do Inferno in Natal/RN. Despite of the fact the locations data from the receiver were collected only the first 70 seconds of flight, this data confirms the correct operation of the receiver by the comparison between its positioning data and the the trajectory data from CLBI s tracking radar named ADOUR
O Sistema de Posicionamento Global, conhecido mundialmente pala sigla GPS, ? um sistema de radionavega??o constru?do pelos norte-americanos com inten??es militares, mas que encontraram, com o passar do tempo, muitas aplica??es de uso civil. No Brasil, al?m do desenvolvimento de foguetes de sondagem, come?am a aparecer projetos de constru??o de micro e nanosat?lites. Estes ve?culos denominados espaciais ou de alta din?mica podem, quando em voo, usufruir do sistema GPS para localiza??o aut?noma e verifica??o/controle das suas trajet?rias. Apesar da enorme disponibilidade de receptores GPS no mercado civil, estes n?o podem ser utilizados em ve?culos de alta din?mica, seja por quest?es ambientais (vibra??es, temperaturas elevadas, etc.) ou por prote??o l?gica (via software). Os receptores para uso em ve?culos de alta din?mica, ou ve?culos espaciais, fazem parte de uma tecnologia restrita a poucos pa?ses, que estabelecem regras muito r?gidas para suas aquisi??es. O presente projeto objetiva construir e validar funcionamento b?sico deste receptor ao instal?-lo num foguete de sondagem e coleta de dados em voo. O software a ser utilizado no receptor j? estava dispon?vel em c?digo fonte e testado em uma plataforma de desenvolvimento denominada GPS Architect. V?rios organismos cooperaram para realiza??o projeto: AEB, UFRN, IAE, INPE e CLBI. Ap?s v?rios passos para realiza??o do projeto: defini??o das condi??es de funcionamento, escolha e aquisi??o dos componentes eletr?nicos, fabrica??o das placas de circuito impresso, montagem e testes de integra??o; o mesmo foi instalado num foguete de sondagem VS30 lan?ado a partir do Centro de Lan?amento da Barreira do Inferno em Natal/RN. Apesar da coleta parcial dos dados do receptor, por falha t?cnica do sistema de telemetria do foguete, os resultados obtidos foram suficientes para validar o funcionamento do receptor a partir da compara??o entre os dados de trajetografia fornecidos pelo receptor GPS e o radar de trajetografia do CLBI conhecido como Radar ADOUR
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Dias, Fábio Luiz. "Estudo da Camada de Basalto em Bebedouro, Bacia do Paraná, com Função do Receptor - Implicações para a Sismicidade Induzida por Poços Profundos". Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/14/14132/tde-12062018-172635/.
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Este trabalho consiste no estudo da estrutura sedimentar da Bacia do Paraná da região de Bebedouro utilizando função do receptor, ondas de superfície e sísmica de refração. Funções do Receptor (FR) mostram a resposta da estrutura geológica abaixo de uma estação sismográfica. Para diminuir a não unicidade na inversão do traço de uma FR, foram usadas curvas de dispersão de ondas de superfície como vínculos adicionais. Ondas de superfície foram também obtidas com a correlação cruzada de ruído sísmico ambiental. Esse método passivo permite a obtenção de dispersão em períodos intermediários entre os dados de telessismos e os dados de sísmica rasa auxiliando na determinação estruturas sedimentares. Foi utilizada a inversão conjunta de FR de alta e baixa frequência, dispersão de fase e grupo de períodos menores que 2 s e dispersão de ondas Love e Rayleigh continentais (períodos entre 10 e 100 s). Na inversão conjunta, foram usados vários modelos iniciais diferentes para garantir melhor cobertura do espaço de soluções possíveis. Os resultados mostram uma camada de basalto com uma espessura entre 200 e 400 m, sob uma camada superficial de arenito de 50 a 100m. O embasamento da bacia está torno de 2.5 3.0 km. A espessura e razão Vp/Vs crustal da região foi estimada em 40.0 (1.0) km e 1.78 (0.02). Foi possível identificar zonas de baixa velocidade dentro do pacote de basalto, possivelmente relacionadas a zonas de fraturas ou camadas de basalto alterado. Estas camadas de baixa velocidade estão na parte sul, próximas à área de maior sismicidade induzida e também relativamente mais perto dos poços profundos de maior vazão. Isto corrobora com a hipótese de que a sismicidade local está associada à exploração de poços e estrutura de falhas pré -existentes.A study of the seismic structure of the Paraná Basin in Bebedouro, SP, was carried out with Receiver Functions (RF). Both low frequency (with ~0.5 Hz low pass filter) and high-frequency (~10Hz) RFs were jointly inverted with surface wave dispersion curves. Surface-wave data included: long-period group velocities of Rayleigh and Love waves from continental-scale tomography in the period range 10-100 s (useful to control crustal scale structure and Moho depth), intermediate period group velocities near 1s period obtained from cross-correlation of ambient noise (useful to control sedimentary structure), phase velocities near 0.2-1.0 s obtained from local earthquakes, and phase velocities of Rayleigh waves from shallow seismic refraction data near ~0.1 s period (useful to control shallow layers). Joint inversion was obtained with several different initial models to better cover all possible solutions. The results indicate that the basalt layer is 200 to 400m thick, beneath sandstones of about 50 100m thick. The Basin basement was detected between 2.5 3.0 km depth, consistent with expected values from regional bore-hole data in the Paraná Basin. Beneath several stations a low-velocity zone was detected in the middle of the basalt pack which is interpreted as a zone of fractured or altered basalt. This anomalous low-velocity layer was detected near the most seismically active zone in the Andes district. It is also relatively close to the deep wells with larger outflow. The existence of this low-velocity zone in the middle of the basalt layer is consistent with the model proposed for the water-well induced seismicity.
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Invernizzi, Rodrigo Candido. "O prazer de ouvir rock and roll: uma análise sob a perspectiva do receptor". Universidade Federal de Goiás, 2017. http://repositorio.bc.ufg.br/tede/handle/tede/7392.
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Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG
The dissertation in question aims at a look at rock and roll with a focus on the listener and on the possible auditory sensations and brain connections occasioned at the moment when the music reaches the receiver. Based on the theoretical discussion about the possibilities of analyzing a work, based on Imbert (1987), we seek to understand where such a fascination for rock and roll comes from, especially the work Rock around the clock (understood here as the music that inaugurates the rock and roll genre). The work methodology consisted of a bibliographical review aiming to contribute with analyzes about the musical genre studied. In order to do so, we initially used the analytical approaches systematized by Imbert (1987), and then, in a second moment, to focus on the analysis of the reception, by the jakobsonian model, of the cultural industry and the imaginary. Finally, we observed the act of fruition, which involved diving into the field of acoustics and psychoacoustics, based on Schafer (1977). It was verified that: the function, the meanings and the feelings attributed to the music also arise from the biological conditions and not only from the socio-cultural references of the artist. In addition, both the acoustic context and the soundscape play important roles in the construction of musical reception theory. Finally, it is suggested the comprehensiveness of the analyzes about rock and roll and the receiver of this musical genre.
A dissertação em questão visa um olhar sobre o rock and roll com foco no ouvinte e nas possíveis sensações auditivas e conexões cerebrais ocasionados no momento em que a música atinge o receptor. A partir da discussão teórica a respeito das possibilidades de análise de uma obra, baseando em Imbert (1987), buscamos entender de onde vem tamanha fascinação pelo rock and roll, em especial pela obra Rock around the clock (entendida aqui como a música que inaugura o gênero rock and roll). A metodologia do trabalho consistiu em revisão bibliográfica com vistas a contribuir com análises a cerca do gênero musical estudado. Para tanto, inicialmente, foram utilizados as abordagens analíticas sistematizadas por Imbert (1987), para posteriormente, em um segundo momento, concentrar na análise da recepção, pelo modelo jakobsoniano, da indústria cultural e do imaginário. Por fim observou-se o ato de fruição, que implicou em mergulhar no campo da acústica e da psicoacústica tendo como base Schafer (1977). Constatou-se que: a função, os significados e os sentidos atribuídos à música brotam também das condições biológicas e não apenas das referências sócio-culturais do fruidor. Além disso, tanto o contexto acústico quanto a paisagem sonora exercem papeis relevantes na construção da teoria da recepção musical. Por fim, sugere-se a abrangência das análises a cerca do rock and roll e do receptor desse gênero musical.
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Raposo, Tullio Emmanuel Messias. "Desenvolvimento e testes de software de um receptor de GPS para uso espacial". Universidade Federal do Rio Grande do Norte, 2011. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15403.
Testo completoAbstract (sommario):
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Previous issue date: 2011-03-25Spacecraft move with high speeds and suffer abrupt changes in acceleration. So, an onboard GPS receiver could calculate navigation solutions if the Doppler effect is taken into consideration during the satellite signals acquisition and tracking. Thus, for the receiver subject to such dynamic cope these shifts in the frequency signal, resulting from this effect, it is imperative to adjust its acquisition bandwidth and increase its tracking loop to a higher order. This paper presents the changes in the GPS Orion s software, an open architecture receiver produced by GEC Plessey Semiconductors, nowadays Zarlink, in order to make it able to generate navigation fix for vehicle under high dynamics, especially Low Earth Orbit satellites. GPS Architect development system, sold by the same company, supported the modifications. Furthermore, it presents GPS Monitor Aerospace s characteristics, a computational tool developed for monitoring navigation fix calculated by the GPS receiver, through graphics. Although it was not possible to simulate the software modifications implemented in the receiver in high dynamics, it was observed that the receiver worked in stationary tests, verified also in the new interface. This work also presents the results of GPS Receiver for Aerospace Applications experiment, achieved with the receiver s participation in a suborbital mission, Operation Maracati 2, in December 2010, using a digital second order carrier tracking loop. Despite an incident moments before the launch have hindered the effective navigation of the receiver, it was observed that the experiment worked properly, acquiring new satellites and tracking them during the VSB-30 rocket flight.
Ve?culos espaciais se movem com velocidades elevadas e sofrem mudan?as bruscas de acelera??o. Ent?o, para que um receptor de GPS possa calcular solu??es de navega??o estando a bordo de tais ve?culos, o efeito Doppler deve ser levado em considera??o durante os processos de aquisi??o e rastreio de sinais de sat?lites. Assim, para que o receptor submetido ? alta din?mica comporte os deslocamentos de frequ?ncia no sinal recebido, decorrentes desse efeito, ? necess?rio ajustar sua largura de banda de varredura de frequ?ncias e aumentar a ordem de sua malha de rastreio. Este trabalho apresenta as modifica??es no software no GPS Orion, um receptor de arquitetura aberta da GEC Plessey Semiconductors, hoje Zarlink, a fim de torn?-lo apto a gerar solu??es de navega??o em ve?culos submetidos ? alta din?mica, especialmente sat?lites de ?rbita baixa. A plataforma de desenvolvimento GPS Architect, comercializada pela mesma empresa, foi utilizada para dar suporte ?s modifica??es. Al?m disso, s?o apresentadas as caracter?sticas do Monitor GPS Aeroespacial, uma ferramenta computacional desenvolvida para monitorar as solu??es de navega??o calculadas pelo receptor de GPS atrav?s de gr?ficos. Apesar de n?o ter sido poss?vel fazer simula??es em alta din?mica com as modifica??es de software implementadas no receptor, verificou-se seu funcionamento satisfat?rio, em regime estacion?rio, fazendo uso, inclusive, da nova interface gr?fica. A disserta??o apresenta ainda os resultados do experimento Receptor de GPS para Aplica??es Aeroespaciais, obtidos com a participa??o do receptor numa miss?o suborbital, a Opera??o Maracati 2, em dezembro de 2010, utilizando uma malha de rastreio de portadora digital de segunda ordem. Apesar de um incidente ocorrido momentos antes do lan?amento ter prejudicado a navega??o efetiva do receptor, foi observado que o experimento funcionou adequadamente, rastreando e adquirindo novos sat?lites durante o voo do foguete VSB-30.
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Mounir, Nabil. "La liberté d'expression publicitaire : réflexions critiques". Thesis, Limoges, 2020. http://www.theses.fr/2020LIMO0057.
Testo completoAbstract (sommario):
L’instauration d’une véritable alliance entre les droits fondamentaux et le marché par l’extension de l’article 10§1 de la CEDH au discours publicitaire pourrait menacer la majesté de l’instrument conventionnel. Dépassant l’étonnement et les critiques suscités par la fondamentalisation de la publicité commerciale, notre étude s’est penchée sur le poids réel que pourrait avoir la liberté d’expression dans un domaine aussi complexe que celui de la publicité commerciale. L’enjeu a donc consisté à se poser la question de savoir si l’extension de l’article 10§1 de la CEDH à ce domaine s’avérait judicieuse. De l’étude des aboutissements de la fondamentalisation du discours publicitaire sur le terrain de la liberté d’expression publicitaire de l’émetteur ressort un constat préoccupant. La complexité du domaine de la publicité commerciale et son utilité relative pour le bon fonctionnement de la « société démocratique » affaiblissent le retentissement de la liberté d’expression et rendent finalement la liberté d’expression publicitaire « théorique et illusoire ». Les risques de marchandisation (une liberté au service du marché) et de banalisation (une liberté sans effet) de la liberté d’expression sont alors très présents. Afin de conjurer ces risques tout en conférant une pleine efficacité à cette liberté, une étude prospective menée sur le terrain de la liberté de réception publicitaire était nécessaire et elle s’est avérée fructueuse. Envisagée du point de vue de la réception, l’extension de l’article 10§1 de la CEDH semble produire des effets juridiques. De surcroît, une liberté fondamentale en devenir, la liberté, négative et positive, de réception publicitaire est en mesure de contribuer à la moralisation de la publicité commercialeThe establishment of a true alliance between fundamental rights and the market by extending Article 10§1 of the ECHR to now encompass advertising could threaten the majesty of the conventional instrument. Going beyond the astonishment and criticisms caused by the fundamentalization of commercial advertising, our study investigates the real implications that freedom of expression could have in a field as complex as commercial advertising. The issue at stake was therefore to evaluate whether the extension of article 10§1 of the ECHR to this field is to be considered a judicious decision. On the basis of studies concerned with fundamentalization of advertising speech in the field of the freedom of expression of the sender, a preoccupying conclusion emerges. Both the complexity of the field of commercial advertising and its relative usefulness for the proper functioning of "democratic society" weakens the impact of freedom of expression and ultimately makes freedom of advertising expression "theoretical and illusory". Consequently, the risks of commodification (a freedom at the service of the market) and trivialization (a freedom without effect) of freedom of expression are very likely. In order to remedy these issues meanwhile conferring full effectiveness on this freedom, a prospective study carried out in the field of the receiver's freedom of advertising reception was necessary and proved fruitful. If seen from the reception point of view, the extension of Article 10§1 of the ECHR seems to be having legal effects. Furthermore, a fundamental freedom in the making, the freedom, both negative and positive, of advertising reception is capable of contributing to the moralization of commercial advertising
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Bianchi, Marcelo Belentani de. "Variações da estrutura da crosta, litosfera e manto para a plataforma Sul Americana através de funções do receptor para ondas P e S". Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/14/14132/tde-22092008-121708/.
Testo completoAbstract (sommario):
Utilizamos neste trabalho duas metodologias distintas, a função do receptor com ondas P e a função do receptor com ondas S, para mapear variações da crosta e interfaces do manto (litosfera-astenosfera, 410 km e 660 km) em diferentes estações sismográficas na placa Sul-Americana. No estudo da interface litosfera-astenosfera, por ser o primeiro realizado nesta região, utilizamos as estações temporárias do IAG/USP em conjunto com as estações permanentes da rede mundial cobrindo toda a placa Sul-Americana. O estudo para as outras interfaces (Crosta-Manto, 410 km e 660 km) foi feito com caráter regional, buscando detalhar características da crosta e manto na região estável da placa. Para ambos os métodos os traços (sismogramas) foram rotacionados para o sistema LQT, deconvolvidos, agrupados por pontos de perfuração e por estações, e finalmente empilhados. Nos traços empilhados as fases convertidas de interesse (Ps, Ppps, Ppss+Psps e Sp) foram identificadas e interpretadas. Para a parte estável da placa obtivemos um valor médio de espessura da crosta de 39.4±0.6 km, variando desde 31.0±0.5 km para a província Borborema, até 41.3±1.0 km para a bacia do Paraná, onde aplicamos uma correção para descontar o efeito do sedimento. A razão de velocidade para a crosta, Vp/Vs, apresentou valores mais altos para a bacia do Paraná (~1.75±0.08) e região litorânea oriental (>1.74), enquanto que as regiões cratônicas (cráton São Francisco e Amazônico) apresentaram valores de Vp/Vs baixos (<1.72), chegando até 1.68. O valor médio de Vp/Vs para todas as estações analisadas foi de 1.73±0.02. As variações dos tempos para as interfaces do manto mostraram boa correlação com resultados de tomografia sísmica de outros trabalhos, indicando alterações de até 5% na velocidade das ondas sísmicas para o manto superior sob os crátons, uma deflexão de até 15 km na interface de 660 km para a região Sul da bacia do Paraná e se mostraram bem correlacionadas com as médias globais para as outras região estudadas. Por fim, a espessura da litosfera apresentou valores desde ~40 km, sob as regiões de ilhas oceânicas, até ~160 km, sob as regiões mais estáveis. Para as regiões oceânicas a espessura da litosfera se mostra correlacionada com a idade da placa. À medida que adentramos a parte continental, o limite litosfera-astenosfera se torna menos proeminente, atingindo profundidades maiores no interior dos continentes e menores para as regiões marginais. Para a zona de subducção, observamos duas possíveis litosferas, uma oceânica, subduzindo junto com a placa de Nazca, e outra pertencente à parte continental.Two distinct methodologies, the P- and S-wave receiver functions, are used to map variations in the crustal parameters (thickness and Vp/Vs) and mantle interfaces (lithosphere-asthenosphere, 410 km and 660 km) on a number of different seismograph stations located in the South American plate. The results of the S receiver function for the lithosphere-asthenosphere boundary are the first of this kind ever performed in South American continent and showed the large scale variations of this interface. To perform this study we analyze data from various global permanent stations together with all available data from temporary stations operated by the IAG/USP during the last15 years. For both methods the traces (seismograms) were rotated to the LQT system, deconvolved, grouped by piercing points and stations, and finally stacked. In the stacked traces, the converted phases (Ps, Ppps, Ppss+Psps and Sp) were identified and interpreted. Inside the stable part of the plate we found a mean crustal thickness of 39.4±0.6 km, ranging from 31.0±0.5 km in Borborema Province up to 41.3±1.0 km in the Paraná Basin, where we applied a correction to remove the sediment effects on the crustal estimates. The crustal velocity ratios, Vp/Vs, showed higher values for the Paraná Basin (~1.75±0.08) and Ribeira belt (>1.74), while the cratonic regions (São Francisco and Amazon cratons) showed low values of Vp/Vs (<1.72), down to 1.68. The average Vp/Vs obtained for all stations was equal to 1.73±0.02. The observed times of the converted mantle phases presented a good correlation with other tomographic studies, indicating that the upper mantle for the cratonic roots may be characterized by a variation up to 5% in seismic velocities, a 15 km deflection in the South Paraná 660 km discontinuity (probably due to a decreased temperature caused by the subducted slab); for other regions the converted times were close to the global average. As a final result, the lithospheric thickness presented values ranging from ~40 km under oceanic islands, to ~160 km under the stable continental regions. We found that for the oceanic islands the thickness of the lithosphere is correlated with the age of the plate. When we go further inside the continents, the lithosphere-asthenosphere boundary becomes less sharp, reaching larger depths inside the continents and shallower depths near the continental margin. In the Andean subduction area, we observed two possibles lithospheres, one oceanic, subducting together with the Nazca plate, and another belonging to the Continent, parallel to the crust interface.
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Neto, João Olympio de Araújo. "Análise da precisão e acurácia de pontos georreferenciados com a técnica do código suavizado pela fase da portadora utilizando GPS de simples freqüência". Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/18/18137/tde-29052007-170329/.
Testo completoAbstract (sommario):
A presente dissertação teve como finalidade avaliar a precisão e a discrepância das coordenadas (acurácia) obtidas por meio das observações GPS, no modo estático rápido, medidas com receptores de uma freqüência, empregando-se a técnica de suavização do código C/A pela fase da portadora para diferentes comprimentos de linha base (20, 50, 75, 100, 150, 200 e 300 Km), a partir da estação de monitoramento contínuo da EESC/USP. Essa técnica obteve boa repercussão no Brasil, a partir do momento em que foi permitida sua utilização para fins de georreferenciamento de imóveis rurais, conforme a norma técnica do INCRA, que permite a utilização da suavização do código pela fase da portadora, desde que esta apresente acurácia com valores iguais ou inferiores a 50 cm. Atualmente, trabalhos com tal técnica estão sendo desenvolvidos e aceitos para compor o banco de dados do cadastro rural nacional. Pelos resultados obtidos nesta dissertação, foi possível avaliar que a aplicação dessa técnica não atende à exigência requerida em 100% das medições e, ao mesmo tempo, verificar a diferença entre a precisão do pós-processamento, indicada pelos softwares comerciais e a acurácia dos pontos medidos comparados com os pontos de controle estabelecidos para esse fim.The present dissertation has as objective to evaluate precision and discrepancies of coordinates (accuracy) obtained through GPS observations, in a rapid static method, measured by single frequency, which applies carrier-smoothed-code for different baseline length (20, 50, 75, 100, 150, 200 and 300 km), since continuous monitoring station from EESC/USP. This technique obtained a good repercussion in Brazil, since when its use was legitimate in rural property georeferencing, according to INCRA\'s norma técnica (technical rule), which allows the use of carrier-smoothed-code in view of the fact that presents accuracy with equal or inferior values to 50 cm. Currently, works using such technique are developed and accepted in order to compound database of national rural survey in Brazil. Based on the obtained results it was possible to evaluate that the technique does not guaranteed to requested requirement in 100% of measurements, and at the same time to verify the difference between post-processing precision, indicated by commercial software, as well as measured point accuracy compared with points established for this purposed.
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Akamine, Cristiano. "Contribuições para distribuição, modulação e demodulação do sistema de TV digital ISDB-TB". [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/261229.
Testo completoAbstract (sommario):
Orientador : Yuzo IanoTese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação
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Resumo: Este trabalho apresenta contribuições para o sistema brasileiro de TV digital. Considera-se a incompatibilidade do BTS (Broadcast Transport Stream) com os sistemas de distribuição de TV digital existentes e a dificuldade de implementação do modulador e demodulador ISDB-TB. Em primeiro lugar um algoritmo inovador capaz de realizar a compressão e adaptação do BTS tomando-o compatível com a maioria dos equipamentos comerciais do sistema DVB, é proposto. Em seguida, um detalhamento do funcionamento do modulador e demodulador é realizado utilizando-se expressões matemáticas e resultados obtidos em simulações computacionais. A partir do BTS, foi desenvolvido um simulador do modulador capaz de monitorar a entrada e saída de todos os blocos de processamento. No último estágio, vetores de RF são criados e podem ser utilizados em simulações computacionais e geradores de forma de onda arbitrária. Utilizando vetores de RF de emissoras de TV, foi desenvolvido um simulador do demodulador ISDB-TB. Esse simulador realiza as operações de sincronismo, estimação de canal, demodulação e decodificação de canal. Além disso, monitores da relação sinal ruído, constelação, resposta em frequência, perfil de atraso e taxa de erro de bits são utilizados para monitorar a reconstrução do BTS
Abstract: This paper presents contributions to the Brazilian digital TV system. It considers the incompatibility of (BTS) Broadcast Transport Stream with the existing digital TV distribution systems. The difficulty of implementation of the ISDB-TB modulator and demodulator are also taken into account. Firstly, an innovative algorithm able to compress and adapt the BTS in order to make it compatible with most DVB commercial equipment is implemented. Then, the detailed operation of the modulator and emodulator are obtained sing mathematical expressions and results from computer simulations. Using the BTS, it has been developed a simulator capable of monitoring the modulation input and output of all processing blocks. In the last stage, the RF vectors are created and can be used on computer simulations and arbitrary waveform generators. Using RF vectors of TV stations, an ISDB-Ts demodulator simulator was developed. This simulator performs the operations of synchronization, channel estimation, demodulation and channel decoding. In addition, monitors of signal to noise ratio, constellation, frequency response, delay profile and bit error rate are used to monitor the reconstruction of the BTS
Doutorado
Telecomunicações e Telemática
Doutor em Engenharia Elétrica
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Junior, Renato Ferreira Fernandes. "Protocolo assíncrono de acesso ao meio iniciado pelo receptor para redes de sensores sem fio". Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/18/18153/tde-13122018-161212/.
Testo completoAbstract (sommario):
A internet das coisas é considerada um novo sistema de comunicação que promete otimizar e melhorar diferentes áreas de aplicação com base em módulos sensores e objetos unicamente interligados através da internet. Em aplicações de redes de sensores sem fio em larga escala, as redes possuem características peculiares, como grande quantidade de módulos sensores de baixa potência, consumo limitado e perdas de comunicação intermitentes. Estas redes precisam operar com protocolos escaláveis e eficientes em termos de consumo de energia. Desta forma, esta tese propõe um protocolo multicanal assíncrono iniciado pelo receptor de acesso ao meio para redes de sensores sem fio de baixa potência para aplicações de internet das coisas. Através de uma comparação com soluções já existentes, o protocolo apresentado procura mitigar a colisão de mensagens e as perdas de energia com ociosidade na espera pela comunicação de um transmissor, através de um mecanismo de reconhecimento inicial eficiente. Adicionalmente, é proposto um diagnóstico efetivo de detecção de falha na comunicação ainda no ciclo de comunicação, de forma a auxiliar a economia de energia. Complementarmente, é proposto um mecanismo multicanal baseado no conhecimento do canal da vizinhança, além de serviços de inicialização e manutenção da rede. Para validação da proposta, o protocolo proposto foi comparado tanto com protocolos assíncronos multicanais iniciado pelo receptor quanto com protocolo síncrono relevantes na literatura científica. Os critérios de avaliação utilizados foram medição do consumo, latência e taxa de entrega da rede em diferentes cenários. Os resultados mostraram que o protocolo proposto minimiza o consumo de energia em relação aos protocolos assíncronos, além de melhorar a comunicação quando comparado aos protocolos analisados. Na comparação com o protocolo síncrono, demonstrou desempenho e consumo compatíveis, quando em período de trabalho menor, e consumo reduzido com períodos de trabalho maiores.The Internet of Things is considered a new communication system that promises to optimize and improve different application areas. It is based on sensor modules and intelligent objects only interconnected through the internet. In large-scale wireless sensor network applications, networks have own specific characteristics such as many low-power, limited-power sensor modules with intermittent communication losses. These networks need to operate with scalable, energy-efficient protocols. Thus, this thesis proposes an asynchronous multichannel receiver-initiated MAC protocol for low power wireless sensor networks and internet of things applications. Through a comparison with already existing solutions, the proposed protocol tries to mitigate message containment and the effect of idle listening through an efficient initial recognition mechanism. It is also proposed an effective diagnosis of communication failure detection in the communication cycle, which also helps to save energy. In addition, a multichannel mechanism is proposed based on the knowledge of the neighborhood channel in addition to services of initialization and maintenance of the network. To validate the proposed protocol, evaluations were made for the consumption of each node sensor, the network traffic for each link, the latency and the network delivery rate in a web application. Tests were performed using asynchronous multichannel receiver-initiated and synchronous protocols based on literature scientific. The results show that the proposed protocol minimizes the energy consumption in relation to the asynchronous protocols, besides improving the communication when compared to the analyzed protocols. In the comparison with the synchronous protocol the proposed protocol showed performance and consumption compatible, when in a smaller duty cycles, and reduced consumption with longer duty cycles.
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Júnior, Cláudio Bielenki. "Avaliação do uso de observáveis coletadas com receptores de navegação pessoal para determinação de coordenadas em linhas base curtas". Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/18/18143/tde-23042009-161253/.
Testo completoAbstract (sommario):
Nas últimas décadas o uso de equipamentos para posicionamento, principalmente os receptores de navegação pessoal, ganhou relativa importância, e a aquisição desses receptores aumentou consideravelmente. Estes receptores, entretanto, não foram desenvolvidos para trabalhos que exijam acurácia, pois estimam e armazenam as posições com precisão e acurácia da ordem de 03-15 m, com 95% de probabilidade, não armazenam os dados de código e fase e não possuem antenas com centro de fase determinado. Com a disponibilização do protocolo de transmissão dos dados destes receptores, foram desenvolvidos alguns programas para, estando conectados ao receptor por meio de hardware e software, extrair e registrar as observações de navegação (código CA e fase da portadora). Desta forma, o uso de receptores de navegação pessoal para medições de coordenadas com boa acurácia, em linhas base curtas, pode tornar-se uma grande alternativa para área de mensuração com aplicações na Engenharia de Transportes. O alto custo de outras técnicas frente à proposta deste trabalho à uma das grandes dificuldades encontradas para uma maior acurácia nos trabalhos geodésicos aplicados aos transportes. Neste trabalho procurou-se analisar o processamento de dados da fase portadora L1 e código CA, coletados com receptores de navegação pessoal,obtidos por meio de softwares auxiliares, levando-se em consideração a algumas variáveis como a distância entre as estações, o tempo de rastreio, softwares de processamento e diferentes equipamentos. Os resultados obtidos promissores confirmando as vantagens de armazenamento das observáveis dos receptores de navegação pessoal para o seu posterior pré-processamento para a obtenção de coordenadas acuradas em linhas bases curtas.In recent decades the use of equipment for positioning, particularly the personal navigation receivers gained relative importance, and the acquisition of these receivers has increased considerably. These eceivers, however, were not developed for task that requiring accuracy, because it estimate and store positions with precision and accuracy of the order of 03 to 15 meters, with 95% probability, do not store the code and carrier phase data and have no determined Xntennae center stage. With the provision of the protocol for data transmission of these receivers have been developed some programs and is connected to the receiver by way of hardware and software, extract and record the navigation observable (CA code and carrier phase). Thus, the use of the navigation eceivers staff to measurements of coordinates with good accuracy, based on short baselines, can become a great alternative to main measurement in Transport Engineering applications. The high cost of other technologies front to the proposal in this work is one of the difficulties found for a greater accuracy in the applied transports geodesic works. In this research it is looked to analyze the data processing of the L1 carrying phase and CA code collected with the aid of specific software, taking itself consideration changeable as in the baseline between the stations, the observation time, software and different equipments. The results was promising, confirming the benefits of storage observable from the personal navigation receivers for further post-processing to obtain accurate coordinates in short baselines.