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Monitoring-cycle based fault detection and localization in mesh all-optical networks /Zeng, Hongqing, January 1900 (has links)
Thesis (Ph.D.) - Carleton University, 2007. / Includes bibliographical references (p. 147-162). Also available in electronic format on the Internet.
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Synchronization of Distributed Units without Access to GPSCarlsson, Erik January 2018 (has links)
Time synchronization between systems having no external reference can be an issue in small wireless node-based systems. In this thesis a transceiver is designed and implemented in two separate systems. Then the timing algorithm of "TwoWay Time Transfer" is then chosen to correct any timing error between the two free running clocks of the systems. In conclusion the results are compared towards having both systems get their timing based on GPS timing. / Tidssynkronisering mellan två system som saknar externa referenser kan bli ett problem i små nodbaserade system. I det här arbetet har en sändtagare designats och implementerats i två system. Sedan valdes algoritmen "TwoWay Time Transfer"för att rätta till de timing fel som uppstår mellan systemens separata klockor.I sammanfattningen så jämnförs uppkommna resultat med att ha systemens tid från GPS.
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Design of a High Temperature GaN-Based VCO for Downhole CommunicationsFeng, Tianming 20 February 2017 (has links)
Decreasing reserves of natural resources drives the oil and gas industry to drill deeper and deeper to reach unexploited wells. Coupled with the demand for substantial real-time data transmission, the need for high speed electronics able to operating in harsher ambient environment is quickly on the rise. This paper presents a high temperature VCO for downhole communication system. The proposed VCO is designed and prototyped using 0.25 μm GaN on SiC RF transistor which has extremely high junction temperature capability. Measurements show that the proposed VCO can operate reliably under ambient temperature from 25 °C up to 230 °C and is tunable from 328 MHz to 353 Mhz. The measured output power is 18 dBm with ±1 dB variations over entire covered temperature and frequency range. Measured phase noise at 230 °C is from -121 dBc/Hz to -109 dBc/Hz at 100 KHz offset. / Master of Science
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Technology demonstrator of a novel software defined radio-based aeronautical communications systemCheng, Yongqiang, Xu, Kai J., Hu, Yim Fun, Pillai, Prashant, Baddoo, J., Smith, A., Ali, Muhammad, Pillai, Anju 29 August 2014 (has links)
Yes / This paper presents the architectural design, software implementation, the validation and flight trial results of an aeronautical
communications system developed within the Seamless Aeronautical Networking through integration of Data links Radios and Antennas (SANDRA) project funded by the European 7th Framework Aeronautics and Transport Programme. Based on
Software Defined Radio (SDR) techniques, an Integrated Modular Radio (IMR) platform was developed to accommodate
several radio technologies. This can drastically reduce the size, weight and cost in avionics with respect to current radio
systems implemented as standalone equipment. In addition, the modular approach ensures the possibility to dynamically
reconfigure each radio element to operate on a specific type of radio link. A radio resource management (RRM) framework is
developed in the IMR consisting of a communication manager for the resource allocation and management of the different
radio links and a radio adaptation manager to ensure protocol convergence through IP. The IMR has been validated though
flight trials held at Oberpfaffenhofen, Germany in June 2013. The results presented in the paper validate the flexibility and
scalability of the IMR platform and demonstrate seamless service coverage across different airspace domains through
interworking between the IMR and other components of the SANDRA network. / European Commission
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A High Temperature Wideband Low Noise AmplifierCunningham, Michael Lawrence 27 January 2016 (has links)
As the oil industry continues to drill deeper to reach new wells, electronics are being required to operate at extreme pressures and temperatures. Coupled with substantial real-time data targets, the need for robust high speed electronics is quickly on the rise. This paper presents a high temperature wideband low noise amplifier (LNA) with zero temperature coefficient maximum available gain (ZTCMAG) biasing for a downhole communication system. The proposed LNA is designed and prototyped using 0.25μm GaN on SiC RF transistor technology, which is chosen due to the high junction temperature capability. Measurements show that the proposed LNA can operate reliably up to an ambient temperature of 230°C with a minimum noise figure (NF) of 2.0 dB, gain of 16.1 dB, and P1dB of 19.1 dBm from 230.5MHz — 285.5MHz. The maximum variation with temperature from 25°C to 230°C is 1.53dB for NF and 0.65dB for gain. / Master of Science
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Tracking collar and infrastructure for leopard researchWarnich, Dirk J. 12 1900 (has links)
Thesis (MScEng)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: This project targeted the development of a new tracking collar, trap telemetry system
and supporting infrastructure, to aid researchers from the Cape Leopard Trust. Previously
used collar products had all proven insu cient in some capacity and remote monitoring of
trap sites was also required. Tracking collars are used to identify the movement patterns
of the leopards and through the resulting research, assist in protecting this threatened
species. In the development of the tracking collar and trap telemetry system, a high level
system design was rst formulated, identifying major components that would be required.
Alternative methods for implementation were then considered and the most optimal chosen.
Two di erent modes of communication with the collar were envisioned and designed for.
These would be used to transmit logged coordinates obtained from a GPS receiver back to
researchers. A VHF terrestrial radio link was investigated, but an Iridium Satellite based
solution was ultimately selected. An Iridium Satellite communications system was also used
for transfer of trap state data. Ultimately, a working trap telemetry system was delivered
for use by researchers. The tracking collar system had progressed to a working prototype,
requiring miniaturisation and packaging before deployment. A possible packaging solution
was also identi ed. The trap telemetry system, although displaying certain de ciencies,
provided a capability previously unavailable to researchers. With further development, there
is potential for the tracking collar to provide accurate satellite tracking and communications
in a mass and price combination not previously available. / AFRIKAANSE OPSOMMING: Hierdie projek het as doel die ontwikkeling van 'n nuwe opsporingshalsband, 'n lokval
telemetriese stelsel en die nodige ondersteunende infrastruktuur daarvoor. As hulpmiddels
vir navorsers van Cape Leopard Trust. Geen van die halsband produkte wat tot nou toe
gebruik is, het voldoen aan al die nodige behoeftes nie, en dit was ook nodig om die
lokvalterreine van 'n afstand te kan monitor. Die opsporingshalsbande word gebruik om
die bewegingspatrone van luiperds vas te stel en die navorsing wat daarop volg, help dat
'n bedreigde spesie bewaar word. Die ontwikkeling van die opsporingshalsband en lokval
telemetriese stelsel het begin met die formulering van 'n ho evlak stelselontwerp waarin
die hoofkomponente wat benodig sou wees ge denti seer is. Alternatiewe metodes van
bewerkstelling is daarna oorweeg en die optimale hiervan is gekies. Twee verskillende
metodes van kommunikasie met die halsband is voorgestel en ontwerp. Hierdie sou gebruik
word om die vasgelegte koordinate wat van 'n GPS ontvanger verkry is, na navorsers terug
te versend. 'n Terrestriale radioverbinding is ondersoek, maar 'n Iridium Satelliet-baseerde
oplossing is uiteindelik verkies. 'n Iridium Satelliet kommunikasie stelsel is ook gebruik
vir die oordrag van data aangaande die lokvaltoestand. Uitendelik is 'n werkende lokval
telemetriese stelsel gelewer vir dir gebruik van navorsers. Die opsporingshalsband stelsel
was nou 'n werkende prototipe, wat slegs verklein en toepaslik verpak moes word voor dit
in gebruik geneem kon word. 'n Moontlike oplossing tot die verpakkingsprobleem is ook
identi seer. Die lokval telemetriese stelsel, hoewel dit steeds tekorte toon, voorsien die
navorsers van voorheen onbekombare inligting. Met verder ontwikkeling is daar potensiaal
vir die opsporingshalsband om akkurate satellietopsporing en kommunikasie te voorsien in
'n kombinasie van laer massa, sowel as prys, soos nog nooit voorheen beskikbaar nie.
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Learning from Data in Radio Algorithm DesignO'Shea, Timothy James 06 December 2017 (has links)
Algorithm design methods for radio communications systems are poised to undergo a massive disruption over the next several years. Today, such algorithms are typically designed manually using compact analytic problem models. However, they are shifting increasingly to machine learning based methods using approximate models with high degrees of freedom, jointly optimized over multiple subsystems, and using real-world data to drive design which may have no simple compact probabilistic analytic form.
Over the past five years, this change has already begun occurring at a rapid pace in several fields. Computer vision tasks led deep learning, demonstrating that low level features and entire end-to-end systems could be learned directly from complex imagery datasets, when a powerful collection of optimization methods, regularization methods, architecture strategies, and efficient implementations were used to train large models with high degrees of freedom.
Within this work, we demonstrate that this same class of end-to-end deep neural network based learning can be adapted effectively for physical layer radio systems in order to optimize for sensing, estimation, and waveform synthesis systems to achieve state of the art levels of performance in numerous applications.
First, we discuss the background and fundamental tools used, then discuss effective strategies and approaches to model design and optimization. Finally, we explore a series of applications across estimation, sensing, and waveform synthesis where we apply this approach to reformulate classical problems and illustrate the value and impact this approach can have on several key radio algorithm design problems. / Ph. D. / Radio communications and sensing systems are used pervasively in the modern world every day life to connect phones, computers, smart devices, industrial devices, internet services, space systems, emergency and military users, radar systems, interference monitoring systems, defense electronic systems, and others. Optimizing these systems to function together reliably and efficently in an ever more complex world is becoming increasingly hard and impractical.
Our work introduces a new and radically different method for the design of radio systems by casting them in a new way as artificial intelligence problems relying on the field of machine learning called deep learning to find and optimize their design. We detail and demonstrate the first such deep learning based communciations and sensing systems operating on raw radio signals and quantify their performance when compared to existing methods, showing them to be competitive with and in some cases significantly better performing than state of the art systems today.
These ideas, and the evidence of their viability, are central to the emerging field of machine learning communications systems, and will help to make tomorrow’s wireless systems faster, cheaper, more reliable, more adaptive, more efficient, and lower power than currently possible. In a world of ever increasing complexity and connectedness, this new approach to wireless system design from data using machine learning offers a powerful new strategy to improve systems by directly leveraging the complexity in real world data and experience to find efficiencies where current day approaches and insufficient simplified models and design tools can not.
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Sistema de comunicação de internação hospitalar: avaliação da qualidade das informações / Communication system of the hospital: assessing the quality of the informationBenevides, Plauto Ricardo de Sá e January 2009 (has links)
Made available in DSpace on 2011-05-04T12:36:22Z (GMT). No. of bitstreams: 0
Previous issue date: 2009 / Este estudo visa explorar o Sistema de Comunicação de Internação Hospitalar (CIH) propondo critérios para avaliação da qualidade dos dados, com o objetivo de sinalizar a existência dos aspectos limitantes, e contribuir para a melhoria da qualidade dos dados dessa importante fonte de informação. O trabalho objetiva, também, incentivar o uso do CIH, ressaltando o seu potencial de utilização na epidemiologia e na gestão da saúde do País. Trata-se de um estudo ecológico em um banco de dados em nível nacional, no período de 2007 e 2008. A metodologia adotada na avaliação da qualidade dos dados foi baseada nas experiências do Instituto Canadense de Informação para a Saúde (Canadian Institute for Health Information) e da Rede Interagencial de Informações para a Saúde (Ripsa), adaptando-se seus conceitos e recomendações às necessidades inerentes ao CIH. O estudo demonstrou que, no período analisado, a base de dados do CIH possui fragilidade na coleta das informações, porém tem boa completitude e mostra coerência das informações na série histórica. / This study explored the Communication System for Hospital (CIH) proposing criteria for evaluating the quality of data in order to signal the
existence of the limiting aspects and contribute to the improvement of data quality of this important source of information. The work also aims at encouraging the use of CIH, highlighting its potential use in epidemiology and health management in the country. This is one ecological study in a database at the national level, between 2007 and 2008. The methodology used in
assessing the quality of the data was based on the experiences of the Canadian Institute for Health Information and the Inter-Agency Network for Health Information (Ripsa), adapting its concepts and recommendations to the needs inherent CIH. The study showed that during the period analyzed, the database of the CIH has weakness in the data collection, but has shown good consistency and completeness of the information in the series.
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Evoluční návrh kolektivních komunikací akcelerovaný pomocí GPU / Evolutionary Design of Collective Communications Accelerated by GPUsTyrala, Radek January 2012 (has links)
This thesis provides an analysis of the application for evolutionary scheduling of collective communications. It proposes possible ways to accelerate the application using general purpose computing on graphics processing units (GPU). This work offers a theoretical overview of systems on a chip, collective communications scheduling and more detailed description of evolutionary algorithms. Further, the work provides a description of the GPU architecture and its memory hierarchy using the OpenCL memory model. Based on the profiling, the work defines a concept for parallel execution of the fitness function. Furthermore, an estimation of the possible level of acceleration is presented. The process of implementation is described with a closer insight into the optimization process. Another important point consists in comparison of the original CPU-based solution and the massively parallel GPU version. As the final point, the thesis proposes distribution of the computation among different devices supported by OpenCL standard. In the conclusion are discussed further advantages, constraints and possibilities of acceleration using distribution on heterogenous computing systems.
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