Search results for "Non-line-of-sight propagation"

showing 10 items of 12 documents

Location-Aware MAC Scheduling in Industrial-Like Environment

2018

We consider an environment strongly affected by the presence of metallic objects, that can be considered representative of an indoor industrial environment with metal obstacles. This scenario is a very harsh environment where radio communication has notorious difficulties, as metallic objects create a strong blockage component and surfaces are highly reflective. In this environment, we investigate how to dynamically allocate MAC resources in time to static and mobile users based on context awareness extracted from a legacy WiFi positioning system. In order to address this problem, we integrate our WiFi ranging and positioning system in the WiSHFUL architecture and then define a hypothesis t…

0209 industrial biotechnologyPositioning systemSettore ING-INF/03 - TelecomunicazioniComputer scienceDistributed computingContext awareness020206 networking & telecommunicationsContext (language use)Ranging02 engineering and technologyNon-line-of-sight propagation020901 industrial engineering & automationIndoor localization systemComponent (UML)MAC scheduler0202 electrical engineering electronic engineering information engineeringContext awarenessArchitectureStatistical hypothesis testing
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Design of Wideband MIMO Car-to-Car Channel Models Based on the Geometrical Street Scattering Model

2012

Published version of an article in the journal: Modelling and Simulation in Engineering. Also available from the publisher at: http://dx.doi.org/10.1155/2012/264213 Open access We propose a wideband multiple-input multiple-output (MIMO) car-to-car (C2C) channel model based on the geometrical street scattering model. Starting from the geometrical model, a MIMO reference channel model is derived under the assumption of single-bounce scattering in line-of-sight (LOS) and non-LOS (NLOS) propagation environments. The proposed channel model assumes an infinite number of scatterers, which are uniformly distributed in two rectangular areas located on both sides of the street. Analytical solutions a…

EngineeringArticle Subjectbusiness.industryAutocorrelationMIMOGeneral EngineeringFunction (mathematics)Correlation function (quantum field theory)lcsh:QA75.5-76.95Computer Science Applicationssymbols.namesakeNon-line-of-sight propagationModeling and SimulationVDP::Technology: 500::Information and communication technology: 550::Telecommunication: 552Electronic engineeringsymbolslcsh:Electronic computers. Computer scienceWidebandbusinessDoppler effectReference modelAlgorithmModelling and Simulation in Engineering
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A novel MIMO car-to-car channel model based on the geometrical curved street scattering model

2012

This paper introduces a novel multiple-input multiple-output (MIMO) car-to-car (C2C) channel model, which is based on a geometrical curved street scattering model. Starting from the geometrical model, a MIMO reference channel model is derived under the assumption of a combination of single- and double-bounce scattering in line-of-sight (LOS) and non-LOS (NLOS) propagation environments. The proposed channel model assumes an infinite number of scatterers, which are uniformly distributed on the outer and inner curves of the street. Expressions are presented for the three-dimensional (3D) space-time cross-correlation function (CCF), the temporal autocorrelation function (ACF), and the two-dimen…

EngineeringNon-line-of-sight propagationbusiness.industryScatteringAutocorrelationMathematical analysisMIMOElectronic engineeringFunction (mathematics)Space (mathematics)businessChannel modelsReference model2012 Loughborough Antennas & Propagation Conference (LAPC)
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Deep Non-Line-of-Sight Reconstruction

2020

The recent years have seen a surge of interest in methods for imaging beyond the direct line of sight. The most prominent techniques rely on time-resolved optical impulse responses, obtained by illuminating a diffuse wall with an ultrashort light pulse and observing multi-bounce indirect reflections with an ultrafast time-resolved imager. Reconstruction of geometry from such data, however, is a complex non-linear inverse problem that comes with substantial computational demands. In this paper, we employ convolutional feed-forward networks for solving the reconstruction problem efficiently while maintaining good reconstruction quality. Specifically, we devise a tailored autoencoder architect…

FOS: Computer and information sciencesComputer Science - Machine Learningbusiness.industryComputer scienceComputer Vision and Pattern Recognition (cs.CV)Image and Video Processing (eess.IV)Computer Science - Computer Vision and Pattern RecognitionNonlinear optics020207 software engineering02 engineering and technologyIterative reconstructionInverse problemElectrical Engineering and Systems Science - Image and Video ProcessingAutoencoderRendering (computer graphics)Machine Learning (cs.LG)Non-line-of-sight propagation0202 electrical engineering electronic engineering information engineeringFOS: Electrical engineering electronic engineering information engineering020201 artificial intelligence & image processingComputer visionArtificial intelligencebusiness
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Time dispersion characterization for UWB mobile radio channels between 3.1 and 10.6 GHz

2007

In this paper, a characterization of the UWB mobile radio channel time dispersion is presented. The results provided were obtained from a measurement campaign carried out in a typical indoor office scenario in the band from 3.1 to 10.6 GHz. Time dispersion metrics as delay spread, coherence bandwidth, delay interval and delay window, in both line-of-sight (LOS) and non-line-of-sight (NLOS) conditions are provided.

Mobile radioNon-line-of-sight propagationComputer scienceDispersion (optics)Electronic engineeringMicrowaveCoherence bandwidthMobile radio channelDelay spread2007 IEEE Antennas and Propagation Society International Symposium
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A narrowband MIMO car-to-car channel model based on the geometrical street scattering model

2012

In this paper, we model a narrowband multiple-input multiple-output (MIMO) car-to-car (C2C) channel model based on the geometrical street scattering model. Starting from the geometrical model, a MIMO reference channel model is derived under the assumption of single-bounce scattering in line-of-sight (LOS) and non-LOS (NLOS) propagation environments. In the proposed channel model, an infinite number of scatterers are uniformly distributed in rectangular grids located on both sides of the street. Analytical solutions are presented for the three-dimensional (3D) space-time cross-correlation function (CCF), the temporal autocorrelation function (ACF), and the two-dimensional (2D) space CCF. An …

Non-line-of-sight propagationNarrowbandComputer scienceScatteringMIMOAutocorrelationFunction (mathematics)Communications systemTopologyReference modelSimulationComputer Science::Information Theory2012 International Conference on Selected Topics in Mobile and Wireless Networking
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LCRT: A ToA Based Mobile Terminal Localization Algorithm in NLOS Environment

2009

©2009 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE. Article also available from publisher: http://dx.doi.org/10.1109/VETECS.2009.5073644 Non line-of-sight (NLOS) propagation in range measurement is a key problem for mobile terminal localization. This paper proposes a low computational residual test (LCRT) algorithm that can identify the number of line-of-sight (LOS) transmissions and reduce the computational com…

Non-line-of-sight propagationTime of arrivalComputational complexity theoryVDP::Technology: 500::Information and communication technology: 550::Telecommunication: 552Range (statistics)Probability density functionResidualCramér–Rao boundAlgorithmUpper and lower boundsMathematics
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A geometric street scattering channel model for car-to-car communication systems

2011

This paper presents a geometric street scattering channel model for car-to-car (C2C) communication systems under line-of-sight (LOS) and non-LOS (NLOS) propagation conditions. Starting from the geometric model, we develop a stochastic reference channel model, where the scatterers are uniformly distributed in rectangles in the form of stripes parallel to both sides of the street. We derive analytical expressions for the probability density functions (PDFs) of the angle-of-departure (AOD) and the angle-of-arrival (AOA). We also investigate the Doppler power spectral density (PSD) and the autocorrelation function (ACF) of the proposed model, assuming that the mobile transmitter (MT) and the mo…

Scattering channelNon-line-of-sight propagationbusiness.industryComputer scienceMathematical analysisAutocorrelationSpectral densityProbability density functionGeometric modelingTelecommunicationsbusinessRandom variableCommunication channelThe 2011 International Conference on Advanced Technologies for Communications (ATC 2011)
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Mobile-to-mobile fading channels in amplify-and-forward relay systems under line-of-sight conditions: statistical modeling and analysis

2010

Published version of an article from the journal:Annales des Telecommunications/Annals of Telecommunications. The original publication is available at Springerlink. http://dx.doi.org/10.1007/s12243-010-0169-z This paper deals with the modeling and analysis of narrowband mobile-to-mobile (M2M) fading channels for amplify-and-forward relay links under line-of-sight (LOS) conditions. It is assumed that a LOS component exists in the direct link between the source mobile station (SMS) and the destination mobile station (DMS), as well as in the links via the mobile relay (MR). The proposed channel model is referred to as the multiple-LOS second-order scattering (MLSS) channel model. The MLSS chan…

VDP::Mathematics and natural science: 400::Information and communication science: 420::Communication and distributed systems: 423Computer scienceCommunications systemlaw.inventionNon-line-of-sight propagationNarrowbandRelaylawMobile stationVDP::Technology: 500::Information and communication technology: 550::Telecommunication: 552Computer Science::Networking and Internet ArchitectureElectronic engineeringFadingElectrical and Electronic EngineeringRelay channelComputer Science::Information TheoryCommunication 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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