Time and Frequency: Theory and Fundamentals

Time and Frequency: Theory and Fundamentals
Author: Byron Emerson Blair
Publisher:
Total Pages: 468
Release: 1974
Genre: Atomic frequency standards
ISBN:

Download Time and Frequency: Theory and Fundamentals Book in PDF, Epub and Kindle

The document is a tutorial Monograph describing various aspects of time and frequency (T/F). Included are chapters relating to elemental concepts of precise time and frequency; basic principles of quartz oscillators and atomic frequency standards; historical review, recent progress, and current status of atomic frequency standards; promising areas for developing future primary frequency standards; relevance of frequency standards to other areas of metrology including a unified standard concept; statistics of T/F data analysis coupled with the theory and construction of the NBS atomic time scale; an overview of T/F dissemination techniques; and the standards of T/F in the USA. The Monograph addresses both the specialist in the field as well as those desiring basic information about time and frequency. The authors trace the development and scope of T/F technology, its improvement over periods of decades, its status today, and its possible use, applications, and development in days to come.

Time and Frequency

Time and Frequency
Author:
Publisher:
Total Pages: 459
Release: 1974
Genre:
ISBN:

Download Time and Frequency Book in PDF, Epub and Kindle

Foundations of Time-Frequency Analysis

Foundations of Time-Frequency Analysis
Author: Karlheinz Gröchenig
Publisher: Springer Science & Business Media
Total Pages: 367
Release: 2013-12-01
Genre: Technology & Engineering
ISBN: 1461200032

Download Foundations of Time-Frequency Analysis Book in PDF, Epub and Kindle

Time-frequency analysis is a modern branch of harmonic analysis. It com prises all those parts of mathematics and its applications that use the struc ture of translations and modulations (or time-frequency shifts) for the anal ysis of functions and operators. Time-frequency analysis is a form of local Fourier analysis that treats time and frequency simultaneously and sym metrically. My goal is a systematic exposition of the foundations of time-frequency analysis, whence the title of the book. The topics range from the elemen tary theory of the short-time Fourier transform and classical results about the Wigner distribution via the recent theory of Gabor frames to quantita tive methods in time-frequency analysis and the theory of pseudodifferential operators. This book is motivated by applications in signal analysis and quantum mechanics, but it is not about these applications. The main ori entation is toward the detailed mathematical investigation of the rich and elegant structures underlying time-frequency analysis. Time-frequency analysis originates in the early development of quantum mechanics by H. Weyl, E. Wigner, and J. von Neumann around 1930, and in the theoretical foundation of information theory and signal analysis by D.

Radio Wave Propagation Fundamentals, Second Edition

Radio Wave Propagation Fundamentals, Second Edition
Author: Artem Saakian
Publisher: Artech House
Total Pages: 422
Release: 2020-12-31
Genre: Technology & Engineering
ISBN: 1630818453

Download Radio Wave Propagation Fundamentals, Second Edition Book in PDF, Epub and Kindle

This completely updated second edition of an Artech House classic provides a thorough introduction to the basic principles of electromagnetic wave propagation of radio frequencies in real-world conditions, fully updated by including new achievements in theory and technology. It serves as an invaluable daily reference for practitioners in the field and as a complete, organized text on the subject. This comprehensive resource covers a wide range of essential topics, from the classification of radio waves, electromagnetic wave theory, and antennas for RF radio links, to the impact of the earth surface on the propagation of ground waves, atmospheric affects in radio wave propagation, and radio wave reception. The book explores the propagation of the ground radio waves, namely the waves that propagate in vicinity of the earth's surface (e.g., guided by that interface), without involvement of any atmospheric effects. Specifics of the high-frequency (HF) radio propagation due to reflections from ionospheric layers is studied, based on commonly used models of the ionospheric vertical profiles. Scattering of the radio waves of UHF and higher frequency bands from the random variations of the tropospheric refraction index (from tiny air turbulences) are also considered by using the principles of statistical radio-physics. Analysis of propagation conditions on real propagation paths, including analysis of the power budget of the VHF/UHF link to assure its stability (percentage of availability within observation time frame), terrestrial, broadcast, mobile, and satellite RF links are presented. The engineering design of the cellular networks, including LTE 4G, 5G and upcoming higher generations is explored. HF propagation predictions for extremely long-range links design for commercial and military applications are explained. Packed with examples and problems, this book provides a theoretical background for astrophysical, aeronomy and geophysical instrumentation design.

NBS Special Publication

NBS Special Publication
Author:
Publisher:
Total Pages: 954
Release: 1976
Genre: Weights and measures
ISBN:

Download NBS Special Publication Book in PDF, Epub and Kindle

Fundamentals of Time-Dependent Density Functional Theory

Fundamentals of Time-Dependent Density Functional Theory
Author: Miguel A.L. Marques
Publisher: Springer Science & Business Media
Total Pages: 573
Release: 2012-01-21
Genre: Science
ISBN: 3642235182

Download Fundamentals of Time-Dependent Density Functional Theory Book in PDF, Epub and Kindle

There have been many significant advances in time-dependent density functional theory over recent years, both in enlightening the fundamental theoretical basis of the theory, as well as in computational algorithms and applications. This book, as successor to the highly successful volume Time-Dependent Density Functional Theory (Lect. Notes Phys. 706, 2006) brings together for the first time all recent developments in a systematic and coherent way. First, a thorough pedagogical presentation of the fundamental theory is given, clarifying aspects of the original proofs and theorems, as well as presenting fresh developments that extend the theory into new realms—such as alternative proofs of the original Runge-Gross theorem, open quantum systems, and dispersion forces to name but a few. Next, all of the basic concepts are introduced sequentially and building in complexity, eventually reaching the level of open problems of interest. Contemporary applications of the theory are discussed, from real-time coupled-electron-ion dynamics, to excited-state dynamics and molecular transport. Last but not least, the authors introduce and review recent advances in computational implementation, including massively parallel architectures and graphical processing units. Special care has been taken in editing this volume as a multi-author textbook, following a coherent line of thought, and making all the relevant connections between chapters and concepts consistent throughout. As such it will prove to be the text of reference in this field, both for beginners as well as expert researchers and lecturers teaching advanced quantum mechanical methods to model complex physical systems, from molecules to nanostructures, from biocomplexes to surfaces, solids and liquids. From the reviews of LNP 706: “This is a well structured text, with a common set of notations and a single comprehensive and up-to-date list of references, rather than just a compilation of research articles. Because of its clear organization, the book can be used by novices (basic knowledge of ground-state DFT is assumed) and experienced users of TD-DFT, as well as developers in the field.” (Anna I. Krylov, Journal of the American Chemical Society, Vol. 129 (21), 2007) “This book is a treasure of knowledge and I highly recommend it. Although it is a compilation of chapters written by many different leading researchers involved in development and application of TDDFT, the contributors have taken great care to make sure the book is pedagogically sound and the chapters complement each other [...]. It is highly accessible to any graduate student of chemistry or physics with a solid grounding in many-particle quantum mechanics, wishing to understand both the fundamental theory as well as the exponentially growing number of applications. [...] In any case, no matter what your background is, it is a must-read and an excellent reference to have on your shelf.” Amazon.com, October 15, 2008, David Tempel (Cambridge, MA)

Quantum Metrology and Fundamental Physical Constants

Quantum Metrology and Fundamental Physical Constants
Author: A.A. Lucas
Publisher: Springer Science & Business Media
Total Pages: 647
Release: 2013-12-01
Genre: Science
ISBN: 1489921451

Download Quantum Metrology and Fundamental Physical Constants Book in PDF, Epub and Kindle

The object of this NATO Advanced Study Institute was to pre sent a tutorial 'introduction both to the basic physics of recent spectacular advances achieved in the field of metrology and to the determination of fundamental physical constants. When humans began to qualify their description of natural phenomena, metrology, the science of measurement, developed along side geometry and mathematics. However, flam antiquity to modern times, the role of metrology was mostly restricted to the need of commercial, social or scientific transactions of local or at most national scope. Beginning with the Renaissance, and particularly in western Europe during the last century, metrology rapidly developed an international character as a result of growing needs for more accurate measurements and common standards in the emerging indus trial society. Although the concerns of metrology are deeply rooted to fundamental sciences, it was, until recently, perceived by much of the scientific community as mostly custodial in character.