The Experts below are selected from a list of 48063 Experts worldwide ranked by ideXlab platform
Emilie Masson - One of the best experts on this subject based on the ideXlab platform.
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Radio Wave propagation in curved rectangular tunnels at 5.8 GHz for metro applications, simulations and measurements
EURASIP Journal on Wireless Communications and Networking, 2011Co-Authors: Emilie Masson, Pierre Combeau, Yann Cocheril, Marion Berbineau, Lilian Aveneau, Rodolphe Vauzelle, Etienne FaytAbstract:Nowadays, the need for wireless communication systems is increasing in transport domain. These systems have to be operational in every type of environment and particularly tunnels for metro applications. These ones can have rectangular, circular or arch-shaped cross section. Furthermore, they can be straight or curved. This article presents a new method to model the Radio Wave propagation in straight tunnels with an arch-shaped cross section and in curved tunnels with a rectangular cross section. The method is based on a Ray Launching technique combining the computation of intersection with curved surfaces, an original optimization of paths, a reception sphere, an IMR technique and a last criterion of paths validity. Results obtained with our method are confronted to results of literature in a straight arch-shaped tunnel. Then, comparisons with measurements at 5.8 GHz are performed in a curved rectangular tunnel. Finally, a statistical analysis of fast fading is performed on these results.
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Radio Wave propagation in arch-shaped tunnels: Measurements and simulations by asymptotic methods
Comptes rendus de l’Académie des sciences. Série IV Physique astrophysique, 2010Co-Authors: Emilie Masson, Pierre Combeau, Yann Cocheril, Marion Berbineau, Lilian Aveneau, Rodolphe VauzelleAbstract:Several wireless communication systems are developed for communication needs between train and ground and between trains in the railway or mass transit domains. They are developed for operational needs for security and comfort. In order to deploy these systems in specific environments, such as tunnels, straight or curved, rectangular or arch-shaped section, specific propagation models have to be developed. A modelisation of the Radio Wave propagation in straight arch-shaped tunnels is realized by using asymptotic methods, such as Ray Tracing and Ray Launching, combined with the tessellation of the arched section. A method of interpolation of the facets' normals was implemented in order to minimize the error made when using the tessellation. Results obtained are validated by comparison to the literature and to measurement results.
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Radio Wave Propagation in Arched Cross Section Tunnels - Simulations and Measurements
Journal of Communication, 2009Co-Authors: Emilie Masson, Pierre Combeau, Marion Berbineau, Rodolphe Vauzelle, Yannis PoussetAbstract:For several years, wireless communication systems have been developed for train to infrastructure communication needs related to railway or mass transit applications. The systems should be able to operate in specific environments, such as tunnels. In this context, specific Radio planning tools have to be developed to optimize system deployment. Realistic tunnels geometries are generally of rectangular cross section or arch-shaped. Furthermore, they are mostly curved. In order to calculate electromagnetic Wave propagation in such tunnels, specific models have to be developed. Several works have dealt with retransmission of GSM or UMTS. Few theoretical or experimental works have focused on 2.4 GHz or 5.8 GHz bands. In this paper, we propose an approach to model Radio Wave propagation in these frequency bands in straight arch-shaped tunnels using tessellation in multi-facets. The model is based on a Ray Tracing tool using the image method. The work reported in this paper shows the propagation loss variations according to the shape of tunnels. A parametric study on the facets size to model the cross section is conducted. The influence of tunnel dimensions and signal frequency is examined. Finally, some measurement results in a straight arch-shaped tunnel are presented and analyzed in terms of slow and fast fading.
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Simulation of Radio Wave propagation in arched cross section tunnels
2008Co-Authors: Emilie Masson, Pierre Combeau, Marion Berbineau, Rodolphe VauzelleAbstract:Since several years, wireless communication systems are developed for train to infrastructure communication needs related to railway or mass transit applications. The systems should be able to operate in specific environments like tunnels. In this context, specific Radio planning tools have to be developed to optimise system deployment. Realistic tunnels geometries are generally of rectangular cross-section or arched shape. Furthermore, they are mostly curved. In order to calculate electromagnetic Wave propagation in such tunnels, specific models have to be developed. Several works dealt with retransmission of GSM or UMTS [1], [2]. Few theoretical or experimental works focused on 2.4 GHz or 5.8 GHz bands. In this paper, we will propose an approach to model Radio Wave propagation in these frequency bands in arched shape cross-section straight tunnels using tessellation in multi-facets. The model will be based on a Ray-Tracing tool using images method. Work reported in this paper will also show the propagation loss variations according to the shape of tunnels. A parametric study on the size of facets to model the cross-section will be realized. Finally, the influence of some parameters like the dimensions of tunnels and the frequency of signals will be examined.
Rodolphe Vauzelle - One of the best experts on this subject based on the ideXlab platform.
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Radio Wave propagation in curved rectangular tunnels at 5.8 GHz for metro applications, simulations and measurements
EURASIP Journal on Wireless Communications and Networking, 2011Co-Authors: Emilie Masson, Pierre Combeau, Yann Cocheril, Marion Berbineau, Lilian Aveneau, Rodolphe Vauzelle, Etienne FaytAbstract:Nowadays, the need for wireless communication systems is increasing in transport domain. These systems have to be operational in every type of environment and particularly tunnels for metro applications. These ones can have rectangular, circular or arch-shaped cross section. Furthermore, they can be straight or curved. This article presents a new method to model the Radio Wave propagation in straight tunnels with an arch-shaped cross section and in curved tunnels with a rectangular cross section. The method is based on a Ray Launching technique combining the computation of intersection with curved surfaces, an original optimization of paths, a reception sphere, an IMR technique and a last criterion of paths validity. Results obtained with our method are confronted to results of literature in a straight arch-shaped tunnel. Then, comparisons with measurements at 5.8 GHz are performed in a curved rectangular tunnel. Finally, a statistical analysis of fast fading is performed on these results.
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Radio Wave propagation in arch-shaped tunnels: Measurements and simulations by asymptotic methods
Comptes rendus de l’Académie des sciences. Série IV Physique astrophysique, 2010Co-Authors: Emilie Masson, Pierre Combeau, Yann Cocheril, Marion Berbineau, Lilian Aveneau, Rodolphe VauzelleAbstract:Several wireless communication systems are developed for communication needs between train and ground and between trains in the railway or mass transit domains. They are developed for operational needs for security and comfort. In order to deploy these systems in specific environments, such as tunnels, straight or curved, rectangular or arch-shaped section, specific propagation models have to be developed. A modelisation of the Radio Wave propagation in straight arch-shaped tunnels is realized by using asymptotic methods, such as Ray Tracing and Ray Launching, combined with the tessellation of the arched section. A method of interpolation of the facets' normals was implemented in order to minimize the error made when using the tessellation. Results obtained are validated by comparison to the literature and to measurement results.
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Radio Wave Propagation in Arched Cross Section Tunnels - Simulations and Measurements
Journal of Communication, 2009Co-Authors: Emilie Masson, Pierre Combeau, Marion Berbineau, Rodolphe Vauzelle, Yannis PoussetAbstract:For several years, wireless communication systems have been developed for train to infrastructure communication needs related to railway or mass transit applications. The systems should be able to operate in specific environments, such as tunnels. In this context, specific Radio planning tools have to be developed to optimize system deployment. Realistic tunnels geometries are generally of rectangular cross section or arch-shaped. Furthermore, they are mostly curved. In order to calculate electromagnetic Wave propagation in such tunnels, specific models have to be developed. Several works have dealt with retransmission of GSM or UMTS. Few theoretical or experimental works have focused on 2.4 GHz or 5.8 GHz bands. In this paper, we propose an approach to model Radio Wave propagation in these frequency bands in straight arch-shaped tunnels using tessellation in multi-facets. The model is based on a Ray Tracing tool using the image method. The work reported in this paper shows the propagation loss variations according to the shape of tunnels. A parametric study on the facets size to model the cross section is conducted. The influence of tunnel dimensions and signal frequency is examined. Finally, some measurement results in a straight arch-shaped tunnel are presented and analyzed in terms of slow and fast fading.
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Simulation of Radio Wave propagation in arched cross section tunnels
2008Co-Authors: Emilie Masson, Pierre Combeau, Marion Berbineau, Rodolphe VauzelleAbstract:Since several years, wireless communication systems are developed for train to infrastructure communication needs related to railway or mass transit applications. The systems should be able to operate in specific environments like tunnels. In this context, specific Radio planning tools have to be developed to optimise system deployment. Realistic tunnels geometries are generally of rectangular cross-section or arched shape. Furthermore, they are mostly curved. In order to calculate electromagnetic Wave propagation in such tunnels, specific models have to be developed. Several works dealt with retransmission of GSM or UMTS [1], [2]. Few theoretical or experimental works focused on 2.4 GHz or 5.8 GHz bands. In this paper, we will propose an approach to model Radio Wave propagation in these frequency bands in arched shape cross-section straight tunnels using tessellation in multi-facets. The model will be based on a Ray-Tracing tool using images method. Work reported in this paper will also show the propagation loss variations according to the shape of tunnels. A parametric study on the size of facets to model the cross-section will be realized. Finally, the influence of some parameters like the dimensions of tunnels and the frequency of signals will be examined.
Mykola Gordovskyy - One of the best experts on this subject based on the ideXlab platform.
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anisotropic Radio Wave scattering and the interpretation of solar Radio emission observations
The Astrophysical Journal, 2019Co-Authors: Eduard P Kontar, Xingyao Chen, Nicolina Chrysaphi, Natasha L S Jeffrey, Gordon A Emslie, V Krupar, Milan Maksimovic, Mykola GordovskyyAbstract:American Astronomical Society logo iop-2016.png A publishing partnership Anisotropic Radio-Wave Scattering and the Interpretation of Solar Radio Emission Observations Eduard P. Kontar1, Xingyao Chen1,2, Nicolina Chrysaphi1, Natasha L. S. Jeffrey1,3, A. Gordon Emslie4, Vratislav Krupar5,6, Milan Maksimovic7, Mykola Gordovskyy8, and Philippa K. Browning9 Published 2019 October 17 • © 2019. The American Astronomical Society. All rights reserved. The Astrophysical Journal, Volume 884, Number 2 DownloadArticle PDF DownloadArticle ePub Figures References 206 Total downloads 11 citation on Dimensions. Turn on MathJax Get permission to re-use this article Share this article Share this content via email Share on Facebook Share on Twitter Share on Google+ Share on Mendeley Article information Abstract The observed properties (i.e., source size, source position, time duration, and decay time) of solar Radio emission produced through plasma processes near the local plasma frequency, and hence the interpretation of solar Radio bursts, are strongly influenced by propagation effects in the inhomogeneous turbulent solar corona. In this work, a 3D stochastic description of the propagation process is presented, based on the Fokker–Planck and Langevin equations of Radio-Wave transport in a medium containing anisotropic electron density fluctuations. Using a numerical treatment based on this model, we investigate the characteristic source sizes and burst decay times for Type III solar Radio bursts. Comparison of the simulations with the observations of solar Radio bursts shows that predominantly perpendicular density fluctuations in the solar corona are required, with an anisotropy factor of ~0.3 for sources observed at around 30 MHz. The simulations also demonstrate that the photons are isotropized near the region of primary emission, but the Waves are then focused by large-scale refraction, leading to plasma Radio emission directivity that is characterized by a half width at half maximum of about 40° near 30 MHz. The results are applicable to various solar Radio bursts produced via plasma emission.
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anisotropic Radio Wave scattering and the interpretation of solar Radio emission observations
arXiv: Solar and Stellar Astrophysics, 2019Co-Authors: Eduard P Kontar, Xingyao Chen, Nicolina Chrysaphi, Natasha L S Jeffrey, Gordon A Emslie, V Krupar, Milan Maksimovic, Mykola GordovskyyAbstract:The observed properties (i.e., source size, source position, time duration, decay time) of solar Radio emission produced through plasma processes near the local plasma frequency, and hence the interpretation of solar Radio bursts, are strongly influenced by propagation effects in the inhomogeneous turbulent solar corona. In this work, a 3D stochastic description of the propagation process is presented, based on the Fokker-Planck and Langevin equations of Radio-Wave transport in a medium containing anisotropic electron density fluctuations. Using a numerical treatment based on this model, we investigate the characteristic source sizes and burst decay times for Type III solar Radio bursts. Comparison of the simulations with the observations of solar Radio bursts shows that predominantly perpendicular density fluctuations in the solar corona are required, with an anisotropy factor $\sim 0.3$ for sources observed at around 30~MHz. The simulations also demonstrate that the photons are isotropized near the region of primary emission, but the Waves are then focused by large-scale refraction, leading to plasma Radio emission directivity that is characterized by a half-width-half-maximum of about 40~degrees near 30~MHz. The results are applicable to various solar Radio bursts produced via plasma emission.
Yannis Pousset - One of the best experts on this subject based on the ideXlab platform.
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Radio Wave Propagation in Arched Cross Section Tunnels - Simulations and Measurements
Journal of Communication, 2009Co-Authors: Emilie Masson, Pierre Combeau, Marion Berbineau, Rodolphe Vauzelle, Yannis PoussetAbstract:For several years, wireless communication systems have been developed for train to infrastructure communication needs related to railway or mass transit applications. The systems should be able to operate in specific environments, such as tunnels. In this context, specific Radio planning tools have to be developed to optimize system deployment. Realistic tunnels geometries are generally of rectangular cross section or arch-shaped. Furthermore, they are mostly curved. In order to calculate electromagnetic Wave propagation in such tunnels, specific models have to be developed. Several works have dealt with retransmission of GSM or UMTS. Few theoretical or experimental works have focused on 2.4 GHz or 5.8 GHz bands. In this paper, we propose an approach to model Radio Wave propagation in these frequency bands in straight arch-shaped tunnels using tessellation in multi-facets. The model is based on a Ray Tracing tool using the image method. The work reported in this paper shows the propagation loss variations according to the shape of tunnels. A parametric study on the facets size to model the cross section is conducted. The influence of tunnel dimensions and signal frequency is examined. Finally, some measurement results in a straight arch-shaped tunnel are presented and analyzed in terms of slow and fast fading.
Natasha L S Jeffrey - One of the best experts on this subject based on the ideXlab platform.
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anisotropic Radio Wave scattering and the interpretation of solar Radio emission observations
The Astrophysical Journal, 2019Co-Authors: Eduard P Kontar, Xingyao Chen, Nicolina Chrysaphi, Natasha L S Jeffrey, Gordon A Emslie, V Krupar, Milan Maksimovic, Mykola GordovskyyAbstract:American Astronomical Society logo iop-2016.png A publishing partnership Anisotropic Radio-Wave Scattering and the Interpretation of Solar Radio Emission Observations Eduard P. Kontar1, Xingyao Chen1,2, Nicolina Chrysaphi1, Natasha L. S. Jeffrey1,3, A. Gordon Emslie4, Vratislav Krupar5,6, Milan Maksimovic7, Mykola Gordovskyy8, and Philippa K. Browning9 Published 2019 October 17 • © 2019. The American Astronomical Society. All rights reserved. The Astrophysical Journal, Volume 884, Number 2 DownloadArticle PDF DownloadArticle ePub Figures References 206 Total downloads 11 citation on Dimensions. Turn on MathJax Get permission to re-use this article Share this article Share this content via email Share on Facebook Share on Twitter Share on Google+ Share on Mendeley Article information Abstract The observed properties (i.e., source size, source position, time duration, and decay time) of solar Radio emission produced through plasma processes near the local plasma frequency, and hence the interpretation of solar Radio bursts, are strongly influenced by propagation effects in the inhomogeneous turbulent solar corona. In this work, a 3D stochastic description of the propagation process is presented, based on the Fokker–Planck and Langevin equations of Radio-Wave transport in a medium containing anisotropic electron density fluctuations. Using a numerical treatment based on this model, we investigate the characteristic source sizes and burst decay times for Type III solar Radio bursts. Comparison of the simulations with the observations of solar Radio bursts shows that predominantly perpendicular density fluctuations in the solar corona are required, with an anisotropy factor of ~0.3 for sources observed at around 30 MHz. The simulations also demonstrate that the photons are isotropized near the region of primary emission, but the Waves are then focused by large-scale refraction, leading to plasma Radio emission directivity that is characterized by a half width at half maximum of about 40° near 30 MHz. The results are applicable to various solar Radio bursts produced via plasma emission.
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anisotropic Radio Wave scattering and the interpretation of solar Radio emission observations
arXiv: Solar and Stellar Astrophysics, 2019Co-Authors: Eduard P Kontar, Xingyao Chen, Nicolina Chrysaphi, Natasha L S Jeffrey, Gordon A Emslie, V Krupar, Milan Maksimovic, Mykola GordovskyyAbstract:The observed properties (i.e., source size, source position, time duration, decay time) of solar Radio emission produced through plasma processes near the local plasma frequency, and hence the interpretation of solar Radio bursts, are strongly influenced by propagation effects in the inhomogeneous turbulent solar corona. In this work, a 3D stochastic description of the propagation process is presented, based on the Fokker-Planck and Langevin equations of Radio-Wave transport in a medium containing anisotropic electron density fluctuations. Using a numerical treatment based on this model, we investigate the characteristic source sizes and burst decay times for Type III solar Radio bursts. Comparison of the simulations with the observations of solar Radio bursts shows that predominantly perpendicular density fluctuations in the solar corona are required, with an anisotropy factor $\sim 0.3$ for sources observed at around 30~MHz. The simulations also demonstrate that the photons are isotropized near the region of primary emission, but the Waves are then focused by large-scale refraction, leading to plasma Radio emission directivity that is characterized by a half-width-half-maximum of about 40~degrees near 30~MHz. The results are applicable to various solar Radio bursts produced via plasma emission.
