Spelling suggestions: "subject:"ubiquitous computing"" "subject:"ubiquitous acomputing""
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Personalized location-sensing for context-aware applications.January 2003 (has links)
Yu Sheung Fan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 96-99). / Abstracts in English and Chinese. / Chapter 1. --- Introduction --- p.1 / Chapter 1.1 --- Background: Context-Aware Applications --- p.2 / Chapter 1.1.1 --- Definitions of Context --- p.2 / Chapter 1.1.2 --- Existing Applications --- p.3 / Chapter 1.1.3 --- Review --- p.6 / Chapter 1.2 --- Research Motivation --- p.6 / Chapter 1.3 --- Research Contributions --- p.8 / Chapter 1.4 --- Thesis Outline --- p.8 / Chapter 2. --- Location-sensing Technologies --- p.9 / Chapter 2.1 --- Global Positioning System (GPS) --- p.9 / Chapter 2.2 --- Existing indoor Location-sensing Systems --- p.11 / Chapter 2.2.1 --- Active Badge --- p.11 / Chapter 2.2.2 --- The Bat System --- p.12 / Chapter 2.2.3 --- RADAR --- p.13 / Chapter 2.2.4 --- PinPoint 3D-iD --- p.14 / Chapter 2.2.5 --- Easy Living --- p.15 / Chapter 2.3 --- System Properties and Risks --- p.16 / Chapter 2.3.1 --- Accuracy --- p.17 / Chapter 2.3.2 --- Cost --- p.18 / Chapter 2.3.3 --- User Privacy --- p.18 / Chapter 2.3.4 --- Location Representation --- p.19 / Chapter 2.3.5 --- Other Limitations --- p.20 / Chapter 2.4 --- Design Goals --- p.20 / Chapter 2.4.1 --- Operate Inside Buildings --- p.21 / Chapter 2.4.2 --- Preserve User Privacy --- p.21 / Chapter 2.4.3 --- Low Cost --- p.22 / Chapter 2.4.4 --- Fast Response --- p.22 / Chapter 2.4.5 --- Spatial Recognition --- p.23 / Chapter 2.4.6 --- Easy Administration and Deployment --- p.23 / Chapter 2.5 --- Summary --- p.23 / Chapter 3. --- System Design --- p.25 / Chapter 3.1 --- System Architecture --- p.25 / Chapter 3.2 --- Position-sensing Platform --- p.28 / Chapter 3.2.1 --- Platform Architecture --- p.29 / Chapter 3.2.2 --- Transmission Format --- p.30 / Chapter 3.2.3 --- Distance Measurement --- p.31 / Chapter 3.2.4 --- Position Estimation --- p.32 / Chapter 3.2.5 --- Noise Cancellation --- p.35 / Chapter 3.2.6 --- Location Inference --- p.36 / Chapter 3.3 --- Summary --- p.38 / Chapter 4. --- System Implementation --- p.39 / Chapter 4.1 --- Communication Technologies --- p.39 / Chapter 4.1.1 --- Ultrasound --- p.40 / Chapter 4.1.2 --- Radio Frequency Identification (RFID) --- p.40 / Chapter 4.1.3 --- Infrared Data Association (IrDA) --- p.41 / Chapter 4.1.4 --- Bluetooth --- p.42 / Chapter 4.2 --- Technologies Overview --- p.43 / Chapter 4.2.1 --- Positioning --- p.44 / Chapter 4.2.2 --- Networking --- p.44 / Chapter 4.2.3 --- Communication Protocol --- p.45 / Chapter 4.2.4 --- Range --- p.45 / Chapter 4.2.5 --- Angle Dependency --- p.45 / Chapter 4.2.6 --- Hardware supports --- p.46 / Chapter 4.3 --- Hardware --- p.46 / Chapter 4.3.1 --- Mobile Receiver --- p.46 / Chapter 4.3.2 --- Transmitter --- p.47 / Chapter 4.4 --- Software --- p.47 / Chapter 4.4.1 --- Communication Protocol --- p.48 / Chapter 4.4.2 --- Programming Environment --- p.48 / Chapter 4.4.3 --- Signal Generation Routine --- p.48 / Chapter 4.4.4 --- Position Estimation Routine --- p.50 / Chapter 4.5 --- Summary --- p.53 / Chapter 5. --- Evaluation --- p.55 / Chapter 5.1 --- Platform Calibration --- p.55 / Chapter 5.1.1 --- Outliers Elimination --- p.56 / Chapter 5.1.2 --- Delay Determination --- p.58 / Chapter 5.1.3 --- Window Size Determination --- p.61 / Chapter 5.1.4 --- Revised Position Estimation Algorithm --- p.63 / Chapter 5.2 --- Platform Evaluation - IrDA Figure 5.9: Experimental setup for distance performance evaluation --- p.64 / Chapter 5.2.1 --- Distance Measurement Figure 5.10: IrDA horizontal distance measurement experiment results --- p.66 / Chapter 5.2.2 --- Position Estimation - Static --- p.66 / Chapter 5.2.3 --- Position Estimation - Mobile --- p.68 / Chapter 5.3 --- Platform Evaluation - Bluetooth --- p.69 / Chapter 5.3.1 --- Distance Measurement --- p.69 / Chapter 5.3.2 --- Position Estimation - Static --- p.70 / Chapter 5.3.3 --- Position Estimation ´ؤ Mobile --- p.71 / Chapter 5.4 --- Summary --- p.73 / Chapter 6. --- Applications --- p.74 / Chapter 6.1 --- Potential Applications --- p.74 / Chapter 6.1.1 --- Resource Tracking Systems --- p.75 / Chapter 6.1.2 --- Shopping Assistance System --- p.76 / Chapter 6.1.3 --- Doctor Tracking System --- p.77 / Chapter 6.1.4 --- Tourist Guide Application --- p.78 / Chapter 6.1.5 --- Other Applications --- p.79 / Chapter 6.2 --- System Limitations --- p.79 / Chapter 6.3 --- Summary --- p.79 / Chapter 7. --- Conclusion --- p.80 / Chapter 7.1 --- Summary --- p.80 / Chapter 7.2 --- Future Work --- p.81 / Chapter Appendix A: --- IrDA --- p.86 / Chapter A.1 --- IrDA Physical Layer --- p.86 / Chapter A.2 --- Physical Aspects of IrDA Physical Layer --- p.87 / Chapter A.3 --- Discovering Other IrDA Devices --- p.88 / Chapter A.4 --- Connection of IrDA Devices --- p.89 / Chapter Appendix B: --- Bluetooth --- p.91 / Chapter B.1 --- Bluetooth Stack --- p.91 / Chapter B.2 --- Radio --- p.92 / Chapter B.3 --- Frequency Hopping --- p.92 / Chapter B.4 --- Package Structure --- p.92 / Chapter B.5 --- The Link Controller --- p.93 / Chapter B.6 --- The Link Manager --- p.93 / Chapter B.7 --- Logical Link Control and Adaptation Protocol --- p.94 / Chapter B.8 --- The Service Discovery Protocol --- p.94 / Chapter B.9 --- Encryption and Security --- p.95 / Bibliography --- p.96
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Continuum : a context-aware service-based software infrastucture for ubiquitous computing / Continuum : uma infra-estrutura de software sensível ao contexto e baseada em serviços para a computação ubíquaCosta, Cristiano Andre da January 2008 (has links)
Este trabalho apresenta uma proposta de infra-estrutura de software sensível ao contexto para a computação ubíqua (ubicomp) denominada Continuum. A área de ubicomp, também chamada de computação pervasiva, pressupõe uma forte integração com o mundo real, com foco no usuário e na manutenção de alta transparência. Para o desenvolvimento de aplicativos nesse cenário, é necessária uma infra-estrutura de software adequada. A infra-estrutura projetada é baseada no padrão da arquitetura orientada a serviços (service-oriented architecture ou SOA), fazendo uso de framework e middleware, e empregando uma redefinição da semântica siga-me. Nessa visão redefinida, os usuários podem ir para qualquer lugar carregando os dados e os aplicativos que desejam, os quais podem ser usados de forma imperceptível e integrada com o mundo real (seamless integration). O foco particular desse trabalho é sensibilidade ao contexto: a percepção de características relacionadas aos usuários e ao entorno. No trabalho são considerados os recursos disponíveis no ambiente e é mantida a história dos dados de contexto. Além disso, é proposta a representação do contexto para promover raciocínio e compartilhamento de conhecimento, empregando uma ontologia. Dessa forma, contexto é representado de uma maneira formal e bastante expressiva, diferente de muitas soluções existentes hoje em dia que ainda usam modelos de representação ad hoc. Esta tese está então na interseção destas três áreas principais: infra-estrutura de software para ubicomp, sensibilidade ao contexto e ontologias. No desenvolvimento desta tese, também examina-se o campo da computação ubíqua, e sugere-se um modelo de arquitetura geral que enfrente esses desafios fundamentais. Baseado nos requisitos estabelecidos para esse modelo, propõe-se um conjunto de serviços para o Continuum. Os serviços são projetados considerando o trabalho previamente desenvolvido pelo nosso grupo de pesquisa, mais especificamente o projeto ISAM, e particularmente o middleware EXEHDA. A proposta estende esses projetos, adicionando aspectos que não haviam sido considerados no momento do seu desenvolvimento. Particularmente, o suporte a sensibilidade de contexto é melhorado com a proposta de uma ontologia para a formalização da informação de contexto. Algumas análises, usando a metodologia de estudo de caso, foram conduzidas para apreciar as principais proposições da tese. Baseado nessas avaliações, foram apresentadas algumas lições aprendidas e traçada a conclusão do trabalho. Como resultado, Continuum é uma infra-estrutura de software que endereça muitos aspectos da computação ubíqua, integrando imperceptivelmente diferentes desafios. / The present work is a proposal of a context-aware software infrastructure for ubiquitous computing (ubicomp) named Continuum. The ubicomp area, also called pervasive computing, presupposes a strong integration with the real world, with focus on the user and on keeping high transparency. For the development of applications in this scenario, we need an adequate software infrastructure. The infrastructure designed in this work is based on service-oriented architecture (SOA), making use of framework and middleware, and employing a redefinition of follow-me semantics. In this redefined vision, users can go anywhere carrying the data and application they want, which they can use in a seamlessly integrated fashion with the real world. The specific focus of our work is context awareness: the perception of characteristics related to users and surroundings. We consider the resources available in the environment and keep a history of context data. Furthermore, we propose the representation of context to promote reasoning and knowledge sharing, using ontology. In this way, context is represented in a considerably expressive, formal approach, different from many solutions that exist today, which still use ad hoc representations models. Our work is then at the intersection of these three main areas: software infrastructures for ubicomp, context awareness, and ontologies. In the development of this thesis, we also survey the field of ubiquitous computing, suggesting a general architectural model to deal with its fundamental challenges. Based on the established requirements for this model, we propose a set of services for Continuum. The services are designed considering the previous works developed by our research group, namely ISAM (Infra-estrutura de Suporte às Aplicações Móveis – Mobile Applications Support Infrastructure), and particularly the middleware EXEHDA (Execution Environment for Highly Distributed Applications). We further extend these projects, by adding aspects to them that had not been considered at the time of their development. Particularly, we improve context awareness support, proposing an ontology for the formalization of context information. We have conducted some analysis, using case study methodology, to evaluate the main propositions of our work. Based on these assessments, we present lessons learned and draw the conclusion of our work. As a result, Continuum is a software infrastructure that addresses many aspects of ubiquitous computing, seamlessly integrating many different challenges.
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Innovativeness: One School's Experience of Sustaining Educational ChangeLieux, Maria L. 18 May 2018 (has links)
Abstract
This single, embedded case study focused on educators’ experiences of educational change as they adopted, implemented, and sustained a one-to-one computing innovation over 20 years. The purpose of the study was to explore the innovativeness, the capacity of a school community to take on change for continuous educational improvement over time. Through interviews and focus groups with administrators, teachers, students, and graduates, observations of current classroom practices, and archival data, the study provides an understanding of how individuals experienced change and how a school sustained change over an exceptionally long period of time. Data analysis revealed multiple rationales for the implementation of one-to-one computing, including the development of a constructivist environment, the empowerment of women, preparation of students for college and the 21st century work force, and the need to keep the school’s educational program on the “cutting-edge.” The study of this individual school community suggests the importance of a strong educational philosophy, flexibility of implementation, an environment that encourages risk-taking, and collegiality. The study also demonstrates that change occurred on a continuum and continued to progress as hardware, software, and the Internet evolved, and as faculty became more knowledgeable of the application of the program to teaching and learning.
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[en] AN ARCHITECTURE FOR INFERENCE OF ACTIVITIES OF MOBILE COMPUTING USERS / [pt] UMA ARQUITETURA PARA INFERÊNCIA DE ATIVIDADES DE USUÁRIO DE COMPUTAÇÃO MÓVELJERONIMO SIROTHEAU DE ALMEIDA EICHLER 26 April 2012 (has links)
[pt] A computação ubíqua aliada ao avanço tecnológico de sensores definiu um
novo cenário no qual a integração de diversos recursos computacionais pode
contribuir para que um conjunto de serviços e funcionalidades esteja disponível ao
usuário sempre que necessário. Um subconjunto desta área é de sistemas sensíveis
às atividades realizadas por seus usuários, isto é, sistemas que utilizam
informações sobre o que o usuário está fazendo. Nesses sistemas, mecanismos de
inferência são essenciais para reconhecer ações do usuário e permitir que o
comportamento do sistema se adapte a estas ações. Entretanto, como esses
ambientes são caracterizados por uma elevada troca de informações, o
desenvolvimento deste tipo de sistema não é uma tarefa trivial e possui como
desafios: privacidade, desempenho, complexidade e ambigüidade das informações
coletadas. O objetivo deste trabalho é propor uma arquitetura para sistemas de
inferências de atividades do usuário. Para atingir esse objetivo, definimos um
conjunto de componentes que representam funções especificas do processo de
inferência. Com o objetivo de analisar a viabilidade da arquitetura proposta,
desenvolvemos, avaliamos e relatamos um protótipo de sistema baseado na
arquitetura. / [en] The ubiquitous computing combined with the advance of sensor technology
creates a scenario in which the integration of several computing resources is used
to keep a set of services and features available to the user whenever necessary. A
particular trend in this area is the activity based systems, i.e., systems that are
aware of the activity played by the user. In these systems, inference engine is
essential to recognize user’s actions and allow the systems to adapt its behavior
according to user’s actions. Though, the development of this type of systems is
not a trivial task as the high rate of information exchanged brings challenges
related to privacy, performance and information management. In this work we
propose an architecture for activity inference systems. To achieve this goal, we
define a set of components that perform important roles in the inference process.
Finally, to show the feasibility of this approach, we designed, implemented and
evaluated a system based on the proposed architecture.
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A participatory design approach in the engineering of ubiquitous computing systemsTimothy Cederman-Haysom Unknown Date (has links)
Ubiquitous computing aims to make human-computer interaction as naturalistic and functionally invisible as possible through embedding computing potential within a particular context to support human activity. However, much of ubiquitous computing research is focussed on technical innovation due to the challenges involved with deploying embedded computing, thereby reducing the commitment to the philosophical ideals of ubiquitous computing in research. This dissertation describes the investigation of a participatory approach to technically-complex research in order to understand how our view of the engineering and human challenges changes when the two are approached hand-in-hand. The domain chosen for this system was a dental surgery. Dentistry involves a complex workspace with computer interaction constrained by surgery hygiene. Ubiquitous computing offers a compelling interaction alternative to the keyboard and mouse paradigm in such an environment. A multi-method approach that employed ethnographic research and design prototyping was undertaken with dentists from several different private practices. A series of field studies used ethnographic methods such as observation and interview. Design events explored prototypes with activities such as design games, contextual interviews, role-playing and contextual prototyping. Activities were devised with the aim of providing a level playing field, whereby both designers and participants feel they can contribute equally, with their respective disciplinary knowledge. It was found that methods needed to be carefully chosen, devised and managed, in order to communicate complex concepts with participants and to constrain the design to technically feasible options. The thesis examines the design problem from the perspectives of a variety of different stakeholders within a participatory design framework, reflected upon by means of human-centred action research. Data was gathered through design speculations and observation, and explored using methods such as the Video Card Game and Video Interaction Analysis. Fieldwork was analysed using a multi-stage qualitative analysis process which informed further design collaboration with participants. The analysis of data gathered during design studies with dentists also contributed to the development of a prototype system to validate methodological contributions. The resulting prototype utilised off-the-shelf hardware and software which allowed for innovative customisation and development. In-situ prototyping (defined by the author as “participatory bootstrapping”) and a comprehensive knowledge of the domain afforded the creative application of technology. In addition to contributing to the prototype design, the interpretive understandings drawn from analysis identified how technical ideas were presented and utilised by participants of the studies, and how best to engage busy professionals. The final outcomes of the research were a multimodal ubiquitous computing system for interacting within a dental surgery; the development and implementation of a variety of methods aimed at communicating technical concepts and eliciting user motivations, practices and concerns; and a set of design principles for engineers engaging in design of systems for human use. The research presented within this thesis is primarily part of the field of human-computer interaction, but provides evidence of how engineering development can be influenced by a user-centred participatory approach. The benefits that derive from inclusive methods of design are demonstrated by the evaluation of a prototype that employed such methods. The contribution of this thesis is to demonstrate and delineate methods for developing ubiquitous computing technologies for the context of human use. This led to a set of design principles for the engineering of systems for human use: 1. Technology needs to be robust and simple to appropriate. This allows users to give insights on technology developments and also to allow users to discover for themselves how they would use the technology. 2. An evolving and carefully considered set of methods are needed to elicit communication between practitioners and across disciplines. The gaps in understandings and the different representations that arise across the disciplines provide essential clues to next steps in design. These gaps and differences form tensions that can be exploited productively. 3. Context is important for determining which design steps to take. Rather than abstracting a problem in order to solve it, as is usual in engineering design, the problem should remain grounded in the context of use. It reveals what the real problems are that need to be solved rather than the imagined ones. This requires an appreciation of the situated nature of action and of the variability of work. In turn it also requires an appreciation of what the human can and does do and what the machine should support. 4. Accountability in design is required. There is a fundamental tension between trying to make something work and seeing what really does work; specifically it is necessary to understand when automation is worth it in human machine systems. While engaged in the design process, engineers should ask how much technology should reconfigure human practices because of a useful outcome, rather than attempting to automate and converge devices for its own sake. A clear understanding of the constraints and workings of the work space needs to be balanced with the understandings of the limitations of the technology in order to design a system that improves work practice and empowers the practitioner.
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Sensor systems for positioning and identification in ubiquitous computingJayabharath Kumar, Suri January 2006 (has links)
<p>Technologies for position sensing and identification are important to have in ubiquitous computing environments. These technologies can be used to track users, devices, and artefacts in the physical milieu, for example, locating the position of a cellular phone in av physical environment. The aim of this thesis was to survey and classify available technologies for location sensing and identification. </p><p>We have made a literature study on both commercial and research-oriented systems and technologies for use in indoor and outdoor environments. We compared the characteristics of the underlying sensing technologies with respect to physical size, sensing method, cost, and accuracy. We conclude the thesis with a set of recommendations to developers and discuss the requirements on future sensing technologies and their use in mobile devices and environments.</p>
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Modelling User Tasks and Intentions for Service Discovery in Ubiquitous ComputingIngmarsson, Magnus January 2007 (has links)
<p>Ubiquitous computing (Ubicomp) increases in proliferation. Multiple and ever growing in numbers, computational devices are now at the users' disposal throughout the physical environment, while simultaneously being effectively invisible. Consequently, a significant challenge is service discovery. Services may for instance be physical, such as printing a document, or virtual, such as communicating information. The existing solutions, such as Bluetooth and UPnP, address part of the issue, specifically low-level physical interconnectivity. Still absent are solutions for high-level challenges, such as connecting users with appropriate services. In order to provide appropriate service offerings, service discovery in Ubicomp must take the users' context, tasks, goals, intentions, and available resources into consideration. It is possible to divide the high-level service-discovery issue into two parts; inadequate service models, and insufficient common-sense models of human activities.</p><p>This thesis contributes to service discovery in Ubicomp, by arguing that in order to meet these high-level challenges, a new layer is required. Furthermore, the thesis presents a prototype implementation of this new service-discovery architecture and model. The architecture consists of hardware, ontology-layer, and common-sense-layer. This work addresses the ontology and common-sense layers. Subsequently, implementation is divided into two parts; Oden and Magubi. Oden addresses the issue of inadequate service models through a combination of service-ontologies in concert with logical reasoning engines, and Magubi addresses the issue of insufficient common-sense models of human activities, by using common sense models in combination with rule engines. The synthesis of these two stages enables the system to reason about services, devices, and user expectations, as well as to make suitable connections to satisfy the users' overall goal.</p><p>Designing common-sense models and service ontologies for a Ubicomp environment is a non-trivial task. Despite this, we believe that if correctly done, it might be possible to reuse at least part of the knowledge in different situations. With the ability to reason about services and human activities it is possible to decide if, how, and where to present the services to the users. The solution is intended to off-load users in diverse Ubicomp environments as well as provide a more relevant service discovery.</p> / Report code: LiU-Tek-Lic-2007:14.
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A Framework for Mobile Paper-based ComputingSylverberg, Tomas January 2007 (has links)
<p>Military work-practice is a difficult area of research where paper-based approaches are still extended. This thesis proposes a solution which permits the digitalization of information at the same time as workpractice remains unaltered for soldiers working with maps in the field. For this purpose, a mobile interactive paper-based platform has been developed which permits the users to maintain their current work-flow. The premise of the solution parts from a system consisting of a prepared paper-map, a cellular phone, a desktop computer, and a digital pen with bluetooth connection. The underlying idea is to permit soldiers to take advantage of the information a computerized system can offer, at the same time as the overhead it incurs is minimized. On one hand this implies that the solution must be light-weight, on the other it must retain current working procedures as far as possible. The desktop computer is used to develop new paper-driven applications through the application provided in the development framework, thus allowing the tailoring of applications to the changing needs of military operations. One major component in the application suite is a symbol recognizer which is capable of recognizing symbols parting from a template which can be created in one of the applications. This component permits the digitalization of information in the battlefield by drawing on the paper-map. The proposed solution has been found to be viable, but still there is a need for further development. Furthermore, there is a need to adapt the existing hardware to the requirements of the military to make it usable in a real-world situation.</p>
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Playing with Context : Explicit and Implicit Interaction in Mobile Media ApplicationsHåkansson, Maria January 2009 (has links)
This thesis contributes with insights into how aspects of the surrounding physical and social context can be exploited in the design of mobile media applications for playful use. In this work, context refers to aspects of the immediate surroundings – outside of the device – that can be identified and measured by sensors; for instance environmental aspects like sound, and social aspects like co-located people. Two extensive case studies explore the interplay between users, mobile media, and aspects of context in different ways, and how it can invite playful use. The first case study, Context Photography, uses sensor-based information about the immediate physical surroundings to affect images in real time in a novel digital camera application for everyday creativity. The second, Push!Music, makes it possible to share music both manually and autonomously between co-located people, based on so-called media context, for spontaneous music sharing. The insights gained from the designs, prototypes, and user studies, point at the value of combining explicit and implicit interaction – essentially, the expected and unexpected – to open for playful use. The explicit interaction encouraged users to be active, exploratory, and creative. The implicit interaction let users embrace and exploit dynamic qualities of the surroundings, contributing to making the systems fun, exciting, magical, ‘live’, and real. This combination was facilitated through our approach to context, where sensor-based information was mostly open in use and interpretation, ambiguous, visible, and possible to override for users, and through giving the systems a degree of agency and autonomy. A key insight is that the combination of explicit and implicit interaction allowed both control and a sense of magic in the interaction with the mobile media applications, which together seems to encourage play and playfulness.
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Ultra Wideband Impulse Radio for Wireless Sensing and IdentificationBaghaei Nejad, Majid January 2008 (has links)
Ubiquitous computing and Internet-of-Things (IoT) implies an untapped opportunity in the realm of information and communication technology, in which a large number of micro-devices with communication and/or computing capabilities, provides connectivity for anything, by anyone at anytime and anywhere. Especially, these devices can be equipped with sensors and actuators that interact with our living environment. Barcode, smart contactless card, Radio Frequency Identification (RFID) systems, wireless sensor network (WSN), and smart mobile phones are some examples which can be utilized in ubiquitous computing. RFIDs and WSN have been recognized as the two promising enablers for realization of ubiquitous computing. They have some great features such as low-cost and small- size implementation, non-line of sight operation, sensing possibilities, data storing ability, and positioning. However, there are several challenges which need to be addressed, such as limited life time for battery powered device, maintenance cost, longer operation range, higher data rate, and operation in dense multipath and multiuser environment. Ultra-Wideband Impulse Radio (UWB-IR) with its huge advantages has been recognized as a great solution for future WSN and RFID. UWB-IR technique has the possibility of achieving Gb/s data rate, hundreds of meter operation range, pJ energy per bit, centimeter accuracy of positioning, and low cost implementation. In this work utilization of UWB-IR in WSN and RFID is investigated. A wireless sensor network based on UWB-IR is proposed focusing on low-cost and low-power implementation. Our contribution is to imply two different architectures in base station and sensor nodes to satisfy power, complexity and cost constraints. For sensor nodes, an autonomous UWB-IR detection is proposed, which detects the UWB signal autonomously and no restrict synchronization is required. It reduces the circuit complexity significantly. The performance in term of bit-error-rate is compared with two other common detection techniques. It is shown that the new detection is more robustness to timing jitter and clock skew, which consequently reduces the clock and synchronization requirements considerably. A novel wireless sensing and identification system, based on remote-powered tag with asymmetric wireless link, is proposed. Our innovative contribution is to deploy two different UWB and UHF communication techniques in uplink and downlink respectively. In the proposed system, tags capture the required power supply from different environmental sources (e.g. electromagnetic wave transmitted by a reader) and transmit data through an ultra-low power impulse UWB link. A new communication protocol is devised based on slotted-aloha anti-collision algorithm. By introducing several improvements including of pipelined communication, adaptive frame size, and skipping idle slots, the system throughput of more than 2000 tags/s is achieved. To prove the system concept a single chip integrated tag is implemented in UMC 0.18μm CMOS process. The measurement results show the minimum sensitivity of -18.5 dB (14.1 μW) and adaptive data rate up to 10 Mb/s. It corresponds to 13.9 meters operation range, considering 4W EIRP, a matched antenna to the tag with 0dB gain, and free space path loss. This is a great improvement in operation range and data rate, compared with conventional passive RFID, which data rate is limited to a few hundreds of Kb/s. System integration in a Liquid-Crystal-polymer (LCP) substrate is investigated. The integration of a tunable UWB-IR transmitter and a power scavenging unit are studied. Our contribution includes embedding and modeling the RF components and antenna in substrate and co-optimizing the chip and package with on-chip versus off-chip passives trade-offs. Simulation results verify the potential of system-on-package solution for UWB integration. The effect of antenna miniaturization in a UWB system is studied. Our focus is to scale down a UWB antenna and optimize the performance through the chip-antenna co-design. A tunable impulse- UWB transmitter is designed in two cases - a conventional 50Ω design and a co-design methodology. The simulation results show that the standard 50Ω design technique can not reach the best condition in all cases, when a real antenna is placed into the system. The performance can be improved significantly when doing codesign. The antennas and UWB transmitter performances are evaluated in a given UWB systems. It is shown that the operation distance at a target performance is reduced with antenna scaling factor and it can be compensated by antenna-transceiver co-design. The result proves the importance of antenna-transceiver codesign, which needs to be addressed in the earliest phases of the design flow. / QC 20100701
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