Author: ALEXANDRE.. GUY Publisher: ISBN: Category : Languages : fr Pages : 218
Book Description
CE MEMOIRE DE THESE TRAITE DE LA LINEARISATION D'AMPLIFICATEURS DE PUISSANCE A ETAT SOLIDE UTILISES DANS LES CHARGES UTILES DE SATELLITES D'OBSERVATION DE LA TERRE, DE NAVIGATION ET DE POSITIONNEMENT. L'OBJECTIF DE CE TRAVAIL A ETE DE DETERMINER LA FAISABILITE D'UN SYSTEME DE LINEARISATION QUE NOUS AVONS CHOISI ET DE LE VALIDER EXPERIMENTALEMENT EN BANDE L (DE 1 A 2 GHZ). LA PREMIERE PARTIE PRESENTE L'ENVIRONNEMENT SATELLITAIRE AINSI QUE LE ROLE ET L'ARCHITECTURE D'UNE CHARGE UTILE, ET ENONCE LES NOTIONS FONDAMENTALES DE L'AMPLIFICATION DE PUISSANCE. LA DEUXIEME PARTIE EXPOSE L'ETAT DE L'ART DES PRINCIPAUX SYSTEMES DE LINEARISATION QUE L'ON TROUVE DANS LA LITTERATURE. APRES UNE ETUDE ET UNE SIMULATION DE CES DIFFERENTES METHODES ET LEUR COMPARAISON SELON PLUSIEURS CRITERES ENONCES DANS LE MEMOIRE, LE PRINCIPE DU CARTESIAN FEEDBACK A ETE RETENU POUR LE TYPE D'APPLICATIONS CHOISI. LE TROISIEME CHAPITRE CONCERNE, EN CONSEQUENCE, L'EXPERIMENTATION ET LES SIMULATIONS DU SYSTEME DE LINEARISATION BASE SUR LA METHODE DU CARTESIAN FEEDBACK. UNE MAQUETTE, COMPOSEE D'ELEMENTS VALIDES AU COURS DE DIVERSES AFFAIRES DIRIGEES PAR ALCATEL SPACE INDUSTRIES, ET UN BANC DE MESURES ASSOCIE ONT ETE REALISES. CES DEUX DERNIERES ACTIONS ONT PERMIS DE VALIDER L'APPROCHE UTILISEE EN MONTRANT UNE TRES BONNE ADEQUATION ENTRE LES RESULTATS EXPERIMENTAUX ET CEUX PREDITS PAR LES SIMULATIONS. DANS LA DERNIERE PARTIE, LA METHODE DU SYSTEME D'INDEXATION DU POINT DE SATURATION DE L'AMPLIFICATEUR DE PUISSANCE EST UTILISEE AFIN D'ETUDIER L'AUGMENTATION POSSIBLE DU RENDEMENT EN PUISSANCE AJOUTEE OBTENU A PARTIR DE L'UTILISATION DE LA METHODE DU CARTESIAN FEEDBACK. ENFIN, UNE CONCLUSION EST REALISEE A PARTIR DES RESULTATS OBTENUS ET LES PERSPECTIVES INDUITES PAR CE TRAVAIL SONT EXPOSEES.
Author: Alexander V. Sergienko Publisher: CRC Press ISBN: 1420026607 Category : Science Languages : en Pages : 248
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.
Author: Paolo Prandoni Publisher: Collection Savoir suisse ISBN: 2940222207 Category : Signal processing Languages : en Pages : 392
Book Description
With a novel, less classical approach to the subject, the authors have written a book with the conviction that signal processing should be taught to be fun. The treatment is therefore less focused on the mathematics and more on the conceptual aspects, the idea being to allow the readers to think about the subject at a higher conceptual level, thus building the foundations for more advanced topics. The book remains an engineering text, with the goal of helping students solve real-world problems. In this vein, the last chapter pulls together the individual topics as discussed throughout the book into an in-depth look at the development of an end-to-end communication system, namely, a modem for communicating digital information over an analog channel.
Author: Neil Gershenfeld Publisher: Cambridge University Press ISBN: 9780521580441 Category : Computers Languages : en Pages : 390
Book Description
The Physics of Information Technology explores the familiar devices that we use to collect, transform, transmit, and interact with electronic information. Many such devices operate surprisingly close to very many fundamental physical limits. Understanding how such devices work, and how they can (and cannot) be improved, requires deep insight into the character of physical law as well as engineering practice. The book starts with an introduction to units, forces, and the probabilistic foundations of noise and signalling, then progresses through the electromagnetics of wired and wireless communications, and the quantum mechanics of electronic, optical, and magnetic materials, to discussions of mechanisms for computation, storage, sensing, and display. This self-contained volume will help both physical scientists and computer scientists see beyond the conventional division between hardware and software to understand the implications of physical theory for information manipulation.
Author: Michel Le Bellac Publisher: Cambridge University Press ISBN: 1139457047 Category : Science Languages : en Pages : 179
Book Description
Quantum information and computation is a rapidly expanding and cross-disciplinary subject. This book, first published in 2006, gives a self-contained introduction to the field for physicists, mathematicians and computer scientists who want to know more about this exciting subject. After a step-by-step introduction to the quantum bit (qubit) and its main properties, the author presents the necessary background in quantum mechanics. The core of the subject, quantum computation, is illustrated by a detailed treatment of three quantum algorithms: Deutsch, Grover and Shor. The final chapters are devoted to the physical implementation of quantum computers, including the most recent aspects, such as superconducting qubits and quantum dots, and to a short account of quantum information. Written at a level suitable for undergraduates in physical sciences, no previous knowledge of quantum mechanics is assumed, and only elementary notions of physics are required. The book includes many short exercises, with solutions available to instructors through [email protected].
Author: Martin Vetterli Publisher: Cambridge University Press ISBN: 1139916572 Category : Technology & Engineering Languages : en Pages : 745
Book Description
This comprehensive and engaging textbook introduces the basic principles and techniques of signal processing, from the fundamental ideas of signals and systems theory to real-world applications. Students are introduced to the powerful foundations of modern signal processing, including the basic geometry of Hilbert space, the mathematics of Fourier transforms, and essentials of sampling, interpolation, approximation and compression The authors discuss real-world issues and hurdles to using these tools, and ways of adapting them to overcome problems of finiteness and localization, the limitations of uncertainty, and computational costs. It includes over 160 homework problems and over 220 worked examples, specifically designed to test and expand students' understanding of the fundamentals of signal processing, and is accompanied by extensive online materials designed to aid learning, including Mathematica® resources and interactive demonstrations.
Author: David C. Lay Publisher: ISBN: 9781292020556 Category : Algebras, Linear Languages : en Pages : 800
Book Description
NOTE: This edition features the same content as the traditional text in a convenient, three-hole-punched, loose-leaf version. Books a la Carte also offer a great value--this format costs significantly less than a new textbook. Before purchasing, check with your instructor or review your course syllabus to ensure that you select the correct ISBN. Several versions of Pearson's MyLab & Mastering products exist for each title, including customized versions for individual schools, and registrations are not transferable. In addition, you may need a CourseID, provided by your instructor, to register for and use Pearson's MyLab & Mastering products. xxxxxxxxxxxxxxx For courses in linear algebra.This package includes MyMathLab(R). With traditional linear algebra texts, the course is relatively easy for students during the early stages as material is presented in a familiar, concrete setting. However, when abstract concepts are introduced, students often hit a wall. Instructors seem to agree that certain concepts (such as linear independence, spanning, subspace, vector space, and linear transformations) are not easily understood and require time to assimilate. These concepts are fundamental to the study of linear algebra, so students' understanding of them is vital to mastering the subject. This text makes these concepts more accessible by introducing them early in a familiar, concrete "Rn" setting, developing them gradually, and returning to them throughout the text so that when they are discussed in the abstract, students are readily able to understand. Personalize learning with MyMathLabMyMathLab is an online homework, tutorial, and assessment program designed to work with this text to engage students and improve results. MyMathLab includes assignable algorithmic exercises, the complete eBook, interactive figures, tools to personalize learning, and more.
Author: ALEXANDRE.. GUY
Author: Alain Mallet
Author: Alexander V. Sergienko
Author: Paolo Prandoni
Author: International Atomic Energy Agency
Author: Neil Gershenfeld
Author: Michel Le Bellac
Author: Martin Vetterli
Author: David C. Lay
Author: Patrick Chow