Réalisation et caractérisation d’un laser DFB bi-mode pour applications radio sur fibre

Réalisation et caractérisation d’un laser DFB bi-mode pour applications radio sur fibre PDF Author: Stéphane Ginestar
Publisher:
ISBN:
Category :
Languages : fr
Pages :

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Book Description
La génération de signaux microondes, millimétriques, voire THz par voie optique est actuellement une solution technique privilégiée pour la réalisation de systèmes de (télé)communications mobiles haut débit mais encore, les réseaux de distribution d'oscillateurs locaux et de signaux d'observation ou de radar intrasatellitaires, la distribution de signaux vidéo, la communication automobile, les systèmes de visualisation THz pour la sécurité, etc... Nous reportons ici la réalisation et la caractérisation d'une source optique ultra-compacte en matériau semiconducteur permettant de générer deux modes optiques séparés de la fréquence que l'on désire créer au niveau de la photodétection. Cette source prend la forme d'un laser DFB bi-longueur d'onde émettant dans la gamme de longueurs d'onde autour de 1,55μm. Le composant a été fabriqué chez Alcatel-Thales III-VLab à partir d'une technologie propriétaire de laser DFB et dans le cade du projet Européen IPHOBAC. Différents objectifs avaient été fixés pour ce composant: accordabilité de l'écartement intermodal jusque 300 GHz, largeur de raie de l'ordre du MHz et divergence dans le plan horizontal et vertical de 10°. Le premier objectif a été atteint par la réalisation de deux lasers DFB dont l'écart de pas de réseau est différent de 0,3nm et par la variation des courants d'injection de chaque section. Le second a été globalement atteint par l'utilisation d'une structure active à puits quantiques, une nouvelle version du composant utilisant des boites quantiques devrait remplir complètement cet objectif. Le dernier objectif a été partiellement atteint par la conception et l'adjonction d'un adaptateur de mode en sortie de composant, la divergence obtenue est de 10°x17° (HxV). Dans le plan vertical, les 10° de divergence n'ont pas pu être obtenus principalement à cause de la structure du composant et des limitations que l'on s'était imposées sur la longueur totale de celui-ci.

Réalisation et caractérisation d’un laser DFB bi-mode pour applications radio sur fibre

Réalisation et caractérisation d’un laser DFB bi-mode pour applications radio sur fibre PDF Author: Stéphane Ginestar
Publisher:
ISBN:
Category :
Languages : fr
Pages :

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Book Description
La génération de signaux microondes, millimétriques, voire THz par voie optique est actuellement une solution technique privilégiée pour la réalisation de systèmes de (télé)communications mobiles haut débit mais encore, les réseaux de distribution d'oscillateurs locaux et de signaux d'observation ou de radar intrasatellitaires, la distribution de signaux vidéo, la communication automobile, les systèmes de visualisation THz pour la sécurité, etc... Nous reportons ici la réalisation et la caractérisation d'une source optique ultra-compacte en matériau semiconducteur permettant de générer deux modes optiques séparés de la fréquence que l'on désire créer au niveau de la photodétection. Cette source prend la forme d'un laser DFB bi-longueur d'onde émettant dans la gamme de longueurs d'onde autour de 1,55μm. Le composant a été fabriqué chez Alcatel-Thales III-VLab à partir d'une technologie propriétaire de laser DFB et dans le cade du projet Européen IPHOBAC. Différents objectifs avaient été fixés pour ce composant: accordabilité de l'écartement intermodal jusque 300 GHz, largeur de raie de l'ordre du MHz et divergence dans le plan horizontal et vertical de 10°. Le premier objectif a été atteint par la réalisation de deux lasers DFB dont l'écart de pas de réseau est différent de 0,3nm et par la variation des courants d'injection de chaque section. Le second a été globalement atteint par l'utilisation d'une structure active à puits quantiques, une nouvelle version du composant utilisant des boites quantiques devrait remplir complètement cet objectif. Le dernier objectif a été partiellement atteint par la conception et l'adjonction d'un adaptateur de mode en sortie de composant, la divergence obtenue est de 10°x17° (HxV). Dans le plan vertical, les 10° de divergence n'ont pas pu être obtenus principalement à cause de la structure du composant et des limitations que l'on s'était imposées sur la longueur totale de celui-ci.

Coherent Optical Fiber Communications

Coherent Optical Fiber Communications PDF Author: T. Okoshi
Publisher: Springer Science & Business Media
ISBN: 9789027726773
Category : Technology & Engineering
Languages : en
Pages : 302

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Book Description


Semiconductor TeraHertz Technology

Semiconductor TeraHertz Technology PDF Author: Guillermo Carpintero
Publisher: John Wiley & Sons
ISBN: 1118920406
Category : Technology & Engineering
Languages : en
Pages : 408

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Book Description
Key advances in Semiconductor Terahertz (THz) Technology now promises important new applications enabling scientists and engineers to overcome the challenges of accessing the so-called "terahertz gap". This pioneering reference explains the fundamental methods and surveys innovative techniques in the generation, detection and processing of THz waves with solid-state devices, as well as illustrating their potential applications in security and telecommunications, among other fields. With contributions from leading experts, Semiconductor Terahertz Technology: Devices and Systems at Room Temperature Operation comprehensively and systematically covers semiconductor-based room temperature operating sources such as photomixers, THz antennas, radiation concepts and THz propagation as well as room-temperature operating THz detectors. The second part of the book focuses on applications such as the latest photonic and electronic THz systems as well as emerging THz technologies including: whispering gallery resonators, liquid crystals, metamaterials and graphene-based devices. This book will provide support for practicing researchers and professionals and will be an indispensable reference to graduate students in the field of THz technology. Key features: Includes crucial theoretical background sections to photomixers, photoconductive switches and electronic THz generation & detection. Provides an extensive overview of semiconductor-based THz sources and applications. Discusses vital technologies for affordable THz applications. Supports teaching and studying increasingly popular courses on semiconductor THz technology.

1997 Digest of the IEEE/LEOS Summer Topical Meetings, 11-15 August 1997 at the Queen Elizabeth Hotel, Montreal, Quebec, Canada

1997 Digest of the IEEE/LEOS Summer Topical Meetings, 11-15 August 1997 at the Queen Elizabeth Hotel, Montreal, Quebec, Canada PDF Author:
Publisher:
ISBN:
Category : Broadband communication systems
Languages : en
Pages :

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Book Description


Quantum Communications and Cryptography

Quantum Communications and Cryptography PDF Author: Alexander V. Sergienko
Publisher: CRC Press
ISBN: 1420026607
Category : Science
Languages : en
Pages : 248

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Book Description
All current methods of secure communication such as public-key cryptography can eventually be broken by faster computing. At the interface of physics and computer science lies a powerful solution for secure communications: quantum cryptography. Because eavesdropping changes the physical nature of the information, users in a quantum exchange can easily detect eavesdroppers. This allows for totally secure random key distribution, a central requirement for use of the one-time pad. Since the one-time pad is theoretically proven to be undecipherable, quantum cryptography is the key to perfect secrecy. Quantum Communications and Cryptography is the first comprehensive review of the past, present, and potential developments in this dynamic field. Leading expert contributors from around the world discuss the scientific foundations, experimental and theoretical developments, and cutting-edge technical and engineering advances in quantum communications and cryptography. The book describes the engineering principles and practical implementations in a real-world metropolitan network as well as physical principles and experimental results of such technologies as entanglement swapping and quantum teleportation. It also offers the first detailed treatment of quantum information processing with continuous variables. Technologies include both free-space and fiber-based communications systems along with the necessary protocols and information processing approaches. Bridging the gap between physics and engineering, Quantum Communications and Cryptography supplies a springboard for further developments and breakthroughs in this rapidly growing area.

Experimental Chaos

Experimental Chaos PDF Author: Stefano Boccaletti
Publisher: A I P Press
ISBN:
Category : Mathematics
Languages : en
Pages : 384

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Book Description
The 8th Experimental Chaos Conference again demonstrated the broad spectrum of areas where nonlinear dynamics plays an important role, such as circuits, hydrodynamics, optics, chemistry, fracture dynamics, neuroscience, and cognitive science. Additional contributions outline the trends for development and application of concepts and techniques of nonlinear dynamics.

Ultra Wide Band Antennas

Ultra Wide Band Antennas PDF Author: Xavier Begaud
Publisher: John Wiley & Sons
ISBN: 1118586573
Category : Technology & Engineering
Languages : en
Pages : 217

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Book Description
Ultra Wide Band Technology (UWB) has reached a level of maturity that allows us to offer wireless links with either high or low data rates. These wireless links are frequently associated with a location capability for which ultimate accuracy varies with the inverse of the frequency bandwidth. Using time or frequency domain waveforms, they are currently the subject of international standards facilitating their commercial implementation. Drawing up a complete state of the art, Ultra Wide Band Antennas is aimed at students, engineers and researchers and presents a summary of internationally recognized studies.

MIMO

MIMO PDF Author: Alain Sibille
Publisher: Academic Press
ISBN: 0123821959
Category : Technology & Engineering
Languages : es
Pages : 385

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Book Description
Foreword from Arogyaswami Paulraj, Professor (Emeritus), Stanford University (USA) - The first book to show how MIMO principles can be implemented in today's mobile broadband networks and components - Explains and solves some of the practical difficulties that arise in designing and implementing MIMO systems - Both theory and implementation sections are written in the context of the most recent standards: IEEE 802.11n (WiFi); IEEE 802.16 (WIMAX); 4G networks (3GPP/3GPP2, LTE)

Enabling Technologies for Next Generation Wireless Communications

Enabling Technologies for Next Generation Wireless Communications PDF Author: Mohammed Usman
Publisher: CRC Press
ISBN: 1000328945
Category : Technology & Engineering
Languages : en
Pages : 296

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Book Description
Enabling Technologies for Next Generation Wireless Communications provides up-to-date information on emerging trends in wireless systems, their enabling technologies and their evolving application paradigms. This book includes the latest trends and developments toward next generation wireless communications. It highlights the requirements of next generation wireless systems, limitations of existing technologies in delivering those requirements and the need to develop radical new technologies. It focuses on bringing together information on various technological developments that are enablers vital to fulfilling the requirements of future wireless communication systems and their applications. Topics discussed include spectrum issues, network planning, signal processing, transmitter, receiver, antenna technologies, channel coding, security and application of machine learning and deep learning for wireless communication systems. The book also provides information on enabling business models for future wireless systems. This book is useful as a resource for researchers and practitioners worldwide, including industry practitioners, technologists, policy decision-makers, academicians, and graduate students.

Planar Antenna

Planar Antenna PDF Author: Praveen Kumar Malik
Publisher: Nova Science Publishers
ISBN: 9781685070427
Category : Technology & Engineering
Languages : en
Pages : 406

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Book Description
"This book focuses on recent advances in the field of planar antenna design and their applications in various fields of research including space communication, mobile communication, wireless communication, and wearable applications. Planar antennas are also used in medical applications including microwave imaging, medical implants, hyperthermia treatments, and wireless wellness monitoring. However, most of these applications still use bulky antenna systems which hamper their efficiency and applicability despite high application potential. The primary objective of recent antenna research is the reduction in size and complexity. Students, scholars and researchers are used to doing mathematical modelling and pattern measurements in simulated environments only. Our aim is to show academic and industry researchers as well as advanced students and lecturers in electronics, electrical and instrumentation engineering how to do measurements in real-world environments. This book will present planar antenna design concepts, methods, and techniques to enhance performance parameters, as well as applications for IoTs and device-to-device communication. We will provide the latest techniques used for the design of antennas in terms of their structures, defected ground, MIMO, and fractal design. This book will also address the specific steps to resolve issues in designing antennas and how to design conformal and miniaturized antenna structures for various applications"--