Search results for "Distributed Systems"

showing 10 items of 38 documents

Throughput and energy efficiency comparison of one-hop, two-hop, virtual relay and cooperative retransmission schemes

2010

Paper presented at the 2010 2010 European Wireless Conference. (c) 2010 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works. Paper also available from the publisher: http://dx.doi.org/10.1109/EW.2010.5483469 Two main types of approaches exist for implementing cooperative communications at the MAC layer: virtual-hop relay and cooperative retransmission. While the virtual-hop relay schemes employ relay n…

VDP::Mathematics and natural science: 400::Information and communication science: 420::Communication and distributed systems: 423ComputerSystemsOrganization_COMPUTER-COMMUNICATIONNETWORKSVDP::Technology: 500::Information and communication technology: 550::Telecommunication: 552Data_CODINGANDINFORMATIONTHEORY
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On the Statistical Analysis of the Channel Capacity of Double Rayleigh Channels with Equal Gain Combining in V2V Communication Systems

2010

paper presented at the 2010 IEEE 71st Vehicular Technology Conference, Taipei. (c) 2010 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works. Paper also available from the publisher: http://dx.doi.org/10.1109/VETECS.2010.5494112 In this article, we present a detailed study on the statistical properties of the channel capacity of vehicle-to-vehicle (V2V) fading channels with equal gain combining (EGC). A…

VDP::Mathematics and natural science: 400::Information and communication science: 420::Communication and distributed systems: 423EngineeringSpatial correlationbusiness.industryCumulative distribution functionMIMOProbability density functionChannel capacityChannel state informationVDP::Technology: 500::Information and communication technology: 550::Telecommunication: 552Gamma distributionElectronic engineeringFadingStatistical physicsbusinessComputer Science::Information Theory
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The wheel of collaboration tools

2006

Paper from the 2006 20th anniversary conference on Computer supported cooperative work We present a holistic framework for analyzing and specifying collaboration solutions, developed by an oil and gas company in response to practical needs in supporting integrated collaboration and information management. A typology of collaboration tool capabilities, termed the Wheel of Collaboration Tools (WCT), is described. We assess its contributions, and discuss areas of application and potential further development. Our intent is to stimulate discussion and research related to this type of collaboration modeling.

VDP::Mathematics and natural science: 400::Information and communication science: 420::Communication and distributed systems: 423Information managementTypologyCollaborative softwareKnowledge managementGroupwarebusiness.industryComputer scienceCollaboration toolCollaboration frameworkVDP::Social science: 200::Political science and organizational theory: 240::Public and private administration: 242Collaboration toolsComputer-supported cooperative workbusinessCollaboration prosessesProceedings of the 2006 20th anniversary conference on Computer supported cooperative work
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Performance Analysis of Alamouti Coded OFDM Systems over Rayleigh Fading Channels Correlated in Space and Time

2010

Paper presented at the 2010 IEEE 71st Vehicular Technology Conference, Taipei.(c) 2010 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works. Paper also available from the publisher: http://dx.doi.org/10.1109/VETECS.2010.5493855 This paper deals with the performance analysis of Alamouti coded orthogonal frequency division multiplexing (OFDM) systems over time-varying multipath Rayleigh fading channels. I…

VDP::Mathematics and natural science: 400::Information and communication science: 420::Communication and distributed systems: 423Multipath rayleigh fading channelComputer scienceOrthogonal frequency-division multiplexingData_CODINGANDINFORMATIONTHEORYSpace (mathematics)Expression (mathematics)Signal-to-noise ratioVDP::Technology: 500::Information and communication technology: 550::Telecommunication: 552Computer Science::Networking and Internet ArchitectureElectronic engineeringFadingAlgorithmComputer Science::Information TheoryRayleigh fadingCommunication channel
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Design and Simulation of Narrowband Indoor Radio Propagation Channels under LOS and NLOS Propagation Conditions

2010

Paper presented at the 2010 IEEE 71st Vehicular Technology Conference. (c) 2010 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works. Paper also available from the publisher: http://dx.doi.org/10.1109/VETECS.2010.5494116 This paper deals with the design and simulation of narrowband indoor propagation channels under line-of-sight (LOS) and non-LOS (NLOS) propagation conditions. We propose a reference cha…

VDP::Mathematics and natural science: 400::Information and communication science: 420::Communication and distributed systems: 423Non-line-of-sight propagationNarrowbandComputer scienceAutocorrelationVDP::Technology: 500::Information and communication technology: 550::Telecommunication: 552Electronic engineeringSpectral densityCommunication channel
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An Exact Solution for the Level-Crossing Rate of Shadow Fading Processes Modelled by Using the Sum-of-Sinusoids Principle

2008

Published version of an article in the journal: Wireless Personal Communications. The original publication is available at Springerlink. http://dx.doi.org/10.1007/s11277-008-9512-3 The focus of this paper is on the higher order statistics of spatial simulation models for shadowing processes. Such processes are generally assumed to follow the lognormal distribution. The proposed spatial simulation model is derived from a non-realizable lognormal reference model with given correlation properties by using Rice's sum-of-sinusoids. Both exact and approximate expressions are presented for the level-crossing rate (LCR) and the average duration of fades (ADF) of the simulation model. It is pointed …

VDP::Mathematics and natural science: 400::Information and communication science: 420::Communication and distributed systems: 423Spatial correlationComputer scienceEmphasis (telecommunications)Higher-order statisticsLevel crossingShadow fadingComputer Science ApplicationsExact solutions in general relativityVDP::Technology: 500::Information and communication technology: 550::Telecommunication: 552Log-normal distributionStatisticsApplied mathematicsElectrical and Electronic EngineeringFocus (optics)Wireless Personal Communications
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Statistical properties of the capacity of double Nakagami-m channels

2010

paper presented at the 2010 5th IEEE International Symposium on Wireless Pervasive Computing (ISWPC), Modena, Italy. (c) 2010 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works. Paper also available from the publisher: http://dx.doi.org/10.1109/ISWPC.2010.5483776 In this article, we have presented an extensive statistical analysis of the capacity of double1 Nakagami-m channels. The double Nakagami-m c…

VDP::Mathematics and natural science: 400::Information and communication science: 420::Communication and distributed systems: 423Spatial correlationbusiness.industryComputer scienceCumulative distribution functionNakagami distributionProbability density functionCommunications systemTopologylaw.inventionChannel capacityRelaylawVDP::Technology: 500::Information and communication technology: 550::Telecommunication: 552FadingTelecommunicationsbusiness
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On the Correlation and Ergodic Properties of the Squared Envelope of SOC Rayleigh Fading Channel Simulators

2012

Published version of an article in the journal: Wireless Personal Communications. Also available from the publisher at: http://dx.doi.org/10.1007/s11277-011-0493-2 In this paper, we investigate the correlation and ergodic properties of the squared envelope of a class of autocorrelation-ergodic (AE) sum-of-cisoids (SOC) simulation models for mobile Rayleigh fading channels. Novel closed-form expressions are presented for both the ensemble and the time autocorrelation functions (ACFs) of the SOC simulation model’s squared envelope. These expressions have been derived by assuming that the SOC model’s inphase and quadrature (IQ) components have arbitrary autocorrelation and cross-correlation pr…

VDP::Mathematics and natural science: 400::Information and communication science: 420::Communication and distributed systems: 423Stochastic processmobile communicationsAutocorrelationEstimatorchannel simulatorsComputer Science ApplicationsQuadrature (mathematics)sum-of-cisoidsNarrowbandsum-of-sinusoidsNorm (mathematics)VDP::Technology: 500::Information and communication technology: 550::Telecommunication: 552StatisticsApplied mathematicsErgodic theoryergodic processesElectrical and Electronic EngineeringRayleigh fading channelssquared envelopeMathematicsRayleigh fadingWireless Personal Communications
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Secure, dependable and publicly verifiable distributed data storage in unattended wireless sensor networks

2010

Published version of an article from the journal : Science in China, Series F: Information Sciences. The original publication is available at Spingerlink. http://dx.doi.org/10.1007/s11432-010-0096-7 In unattended wireless sensor networks (UWSNs), sensed data are stored locally or at designated nodes and further accessed by authorized collectors on demand. This paradigm is motivated by certain scenarios where historical or digest data (e.g., average temperature in a day), instead of real-time data, are of interest. The data are not instantly forwarded to a central sink upon sensing, thereby saving communication energy for transmission. Such a paradigm can also improve data survivability by m…

VDP::Mathematics and natural science: 400::Information and communication science: 420::Communication and distributed systems: 423VDP::Technology: 500::Information and communication technology: 550::Computer technology: 551General Computer Sciencebusiness.industryComputer scienceSecret sharingData integrityComputer data storageDistributed data storeDependabilityVerifiable secret sharingbusinessWireless sensor networkByzantine fault toleranceComputer networkScience China Information Sciences
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Performance Analysis of M-Ary PSK Modulation Schemes over Multiple Double Rayleigh Fading Channels with EGC in Cooperative Networks

2010

paper presented at the 2010 IEEE International Conference on Communications Workshops, Cape Town.(c) 2010 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other users, including reprinting/ republishing this material for advertising or promotional purposes, creating new collective works for resale or redistribution to servers or lists, or reuse of any copyrighted components of this work in other works. Paper also available from the publisher: http://dx.doi.org/10.1109/ICCW.2010.5503940 This article studies the performance of M-ary phase shift keying (PSK) modulation schemes over mobile-to-mobile (M2M) fading channels with equal gain combining (…

VDP::Mathematics and natural science: 400::Information and communication science: 420::Communication and distributed systems: 423VDP::Technology: 500::Information and communication technology: 550::Telecommunication: 552
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