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| Registros recuperados: 15 | |
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| Leon, Pierre; Drogou, Jean-francois; Chenot, Damien; Leveque, C.; Martinossi, Henri; Massol, Alain; Rigaud, Vincent; Santarelli, Dominique; Valdy, Pierre; Gojak, Carl; Bernardet, Karim; Hafidi, Zouhir; Lenault, Yannick; Mahiouz, Karim; Deschamps, Anne; Hello, Y.; Lefevre, D.; Tamburini, C.; Destelle, J. J.. |
| Recently the ANTARES Neutrino telescope's Infrastructure in the deep Mediterranean Sea, has been extended by a Secondary Junction Box. The main emphasis has been to provide basic power and communications capability for new scientific cabled observatories. This new infrastructure provides unprecedented amounts of power and two-way bandwidth to access and control instrument networks in the oceans. This new development allows cabled observatory to connect the seafloor to the Internet via real-time, two-way highspeed communications. This design gives researchers new capabilities beyond the reach of traditional oceanography. Ocean scientists can run deep-water experiments from labs and universities anywhere around the world. Three different underwater... |
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| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00050/16173/13658.pdf |
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| Leon, Pierre; Roland, Francois; Brignone, Lorenzo; Opderbecke, Jan; Greer, Jennifer; Khalighi, M. A.; Hamza, Tasnim; Bourennane, S.; Bigand, M.. |
| Silicon Photomultipliers (SiPMs) have recently been recognized as an interesting alternative to photomultiplier tubes (PMTs) thanks to their high sensitivity and time resolution. They can closely approach quantum-limited sensitivity in the detection of weak optical signals. Ifremer (French Research Institute for Exploitation of the Sea) and Institut Fresnel research lab have been investigating appropriate alternative solutions for PMTs in the context of underwater optical communications, and have for the first time used these new photodetector components for signal detection. A novel prototype of an optical modem based on SiPM receivers was realized with support from Osean SAS Co., a French instrumentation company. A number of lab experiments and sea... |
| Tipo: Text |
Palavras-chave: Optical communications; Underwater communications; Silicon photomultipliers; Photomultiplier tubes. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00435/54677/56495.pdf |
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| Marsset, Bruno; Menut, Eric; Ker, Stephan; Thomas, Yannick; Regnault, Jean-pierre; Leon, Pierre; Martinossi, Henri; Artzner, Laurent; Chenot, Damien; Dentrecolas, Stephane; Spychalski, B.; Mellier, G.; Sultan, Nabil. |
| High Resolution (220–1050 Hz) seismic acquisition performed in deep water using deep-towed systems provides unrivalled lateral resolution when compared to conventional surface seismic. The lateral resolution of these acquisitions is controlled by the width of the first Fresnel zone, taking advantage of their positions close to the sea bottom. No current existing deep towed equipment can benefit from seismic imaging processing techniques to improve this resolution as a consequence of positioning inaccuracies. The technological developments of a digital deep-towed multichannel streamer are presented with a particular attention to positioning: each hydrophone incorporates a pitch, roll and heading sensor in order to monitor the constant deformation of the... |
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Palavras-chave: Deep-towed seismics; Multichannel streamer; Seismic imaging. |
| Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00206/31745/35690.pdf |
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| Leon, Pierre. |
| Ce document étudie la faisabilité de la mesure de lumière à implanter sur la nouvelle marque à poissons, développée dans le cadre du projet Merlin POPSTAR. Il rappelle les principes de la géolocalisation par capteur de lumière, les contraintes du canal optique sous-marin, il précise les performances à atteindre, il évalue les capteurs existants et propose des solutions pour la nouvelle marque POPSTAR. |
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| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00377/48847/49278.pdf |
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| Hamza, Tasnim; Khalighi, Mohammad-ali; Bourennane, Salah; Leon, Pierre; Opderbecke, Jan. |
| We investigate the effect of environmental noise, caused by solar radiations under water, on the performance of underwater wireless optical communication (UWOC) systems. Presenting an analytical and generic model for this noise, we examine its impact on the link performance in terms of the bit error rate (BER). This study is conducted for different photo-detector types in the aim of highlighting practical limitations of establishing UWOC links in the presence of subsea solar noise. We show how the solar noise can impact the performance of UWOC links for relatively low operation depths. The results we present provide valuable insight for the design of UWOC links, which are likely to be established at relatively low depths. They can be exploited not only for... |
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| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00362/47272/47234.pdf |
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| Puillat, Ingrid; Lanteri, Nadine; Drogou, Jean-francois; Blandin, Jerome; Geli, Louis; Sarrazin, Jozee; Sarradin, Pierre-marie; Auffret, Yves; Rolin, Jean-francois; Leon, Pierre. |
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| Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00079/19036/16619.pdf |
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| Ker, Stephan; Le Gall, Yves; Marsset, Tania; Leon, Pierre. |
| Ifremer has recently developed a deep-towed seismic system designed for High to Very High resolution near-bottom marine seismic surveys. This paper presents this new tool which is dedicated to the study of deepwater geological objects especially geohazards. After a technical description of the system, we expound an overview of the complete workflow from survey design to amplitude preserved processing illustrated by data acquired during sea trials. |
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| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/00127/23841/21767.pdf |
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| Sarrazin, Jozee; Blandin, Jerome; Delauney, Laurent; Dentrecolas, Stephane; Dorval, Philippe; Dupont, Jacky; Legrand, Julien; Leroux, D.; Leon, Pierre; Leveque, Jean-jacques; Rodier, Philippe; Vuillemin, Renaud; Sarradin, Pierre-marie. |
| The major goal of this project, elaborated in the frame of the STREP Exocet/D European project, was to design a first autonomous long-term imaging module equipped with a deep-sea video camera, adequate lightning and sufficient energy storage while taking advantage of most recent progress in imaging and photonics. The new ecological module TEMPO was tested and deployed during the Momareto cruise held from August 6 to September 6, 2006 on the new French oceanographic vessel Pourquoi pas?, with the ROV Victor 6000. The scientific objectives of the Momareto cruise were to study the spatial and temporal dynamics of hydrothermal communities colonizing the MoMAR zone, located on the Azores Triple Junction. |
| Tipo: Text |
Palavras-chave: Community dynamics; Deep-sea; Imagery; Monitoring. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-3597.pdf |
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| Khalighi, Mohammad-ali; Chadi, Gabriel; Hamza, Tasnim; Bourennane, Salah; Leon, Pierre; Rigaud, Vincent. |
| Because of its ability of providing very high data transmission rates over distances up to several tens of meters, underwater wireless optical communication (UWOC) has attracted considerable interest during the past few years. The underwater channel is a challenging environment, especially because of its high attenuation. The difficulty of precise localization underwater also leads to unavoidable link misalignments that can have an important impact on the link availability and otherwise on the quality of signal transmission. In this paper, after a review of the recent research works on UWOC and the available commercialized systems, we present the performance study of a typical UWOC system under some simplifying assumptions for system modeling. We also... |
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| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00226/33701/32093.pdf |
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| Khalighi, Mohammad-ali; Hamza, Tasnim; Bourennane, Salah; Leon, Pierre; Opderbecke, Jan. |
| We study the use of Silicon photo-multipliers (SiPMs) for underwater wireless optical communications (UWOC) and discuss their main interests and drawbacks, compared with photo-multiplier tubes. This comparison is mainly based on practical considerations regarding system implementation and the attainable link span. Presenting an appropriate model for signal attenuation in water and considering the simple On-Off keying modulation, we bring clearance on the real interest of using an SiPM in the UWOC context. We also elucidate the main drawbacks of these components in practice, in particular, regarding the limitation on the transmission data rate, as well as the nonlinear distortion caused on the received signal in relatively short ranges, where the signal... |
| Tipo: Text |
Palavras-chave: Underwater wireless optical communications; Silicon photo-multiplier; Singlephoton avalanche diode; Photo-multiplier tube; Underwater optical channel. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00396/50726/51434.pdf |
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| Registros recuperados: 15 | |
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