Quantum key distribution (QKD) is one of the first quantum technologies that were able to provide commercially meaningful solutions to the problem of distributing cryptographic keys between trusted parties, guaranteeing long term security. It is now progressing towards technical maturity, by proposing multiple implementation alternatives. In this t...
An optical link based on a multiplex of wavelengths at 1.55µm is foreseen to be a valuable alternative to the conventional radio-frequencies for the feeder link of the next-generation of high throughput geostationary satellite. Considering the limited power of lasers envisioned for feeder links, the beam divergence has to be dramatically reduced. C...
Dynamic and flexible optical networks are among the evolution scenarios of the optical transport networks. These form the basis of the new generation of optical networks of tomorrow and enable the effective deployment of services such as cloud computing. This evolution is intended to provide flexibility and automation to the optical layer. However,...
This PhD dissertation presents a study on the properties of the novel quantum dash nanostructures and their properties for application in optical telecommunications. Over the last decade, scientific community has gained considerable interest over these nanostructures and several demonstrations have been made on their interesting optical and electro...
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La demande en capacité liée à la transmission de tout type d information (voix, vidéos, données, etc.) ne cesse de croître. Afin de répondre à cette demande croissante, de nouvelles générations de systèmes de communication multiplexés en longueur d onde transmettant des débits élevés d information par canal (100 Gbit/s ou plus) doivent être conçues...
La complexité des systèmes de télécommunications par fibre optique évolue rapidement de façon à offrir plus de bande passante. Comme ce fut le cas pour l’industrie de la microélectronique, l’intégration de composants photoniques avancés est requise pour la production de composants de haute qualité aux fonctions multiples. C’est dans ce contexte, qu...
Cette thèse aborde la performance du codage de canal pour les communications optiques sans fil indoor. L application visée concerne la télésurveillance des données physiologiques de patients mobiles en milieu hospitalier. Après avoir présenté les caractéristiques des liens optiques infrarouges en visibilité directe et en diffus, les techniques perm...
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In this thesis, we have studied a Radio-over-Fibre Distributed Antenna System for WLAN IEEE802.11g OFDM at 2.45 GHz. By analyzing the model and the characteristics of the optical link, we have studied the limitations of such system, and then proposed the technical solution. Because of the high noise figure and the low compression point of the optic...
