Perspectives in Spread Spectrum brings together studies and recent work on six exciting topics from the spread spectrum arts. The book gives a wide, collective view of trends, ideas, and techniques in the spread spectrum discipline, due to the authors' extensive work on spread spectrum techniques and applications from different vantage points. The inexorable march of electronics towards ever faster, ever smaller, and ever more powerful electronic and optical circuitry has wrought, and will continue to enable, profound changes in the spread spectrum arts, by allowing increasingly complex signalling waveforms and statistical tests to be implemented as the theory beyond spread spectrum continues to evolve. Perspectives in Spread Spectrum is divided into six chapters. The first chapter deals with sequence spreading design. There is not a single metric for design of spreading sequences; rather, the design is ideally tailored to the specific scenario of usage. This chapter delves into recent and very promising synthesis work. The second chapter deals with OFDM techniques. As channels become wider and trans-channel fading (or jamming) becomes frequency selective across the band, OFDM techniques may provide a powerful alternative design perspective. The third chapter is a generalization of the venerable Walsh functions. A new modulation scheme, Geometric Harmonic Modulation, GHM for short, is reviewed and characterized as a form of OFDM. From GHM, a further generalization of the Walsh functions is derived for non-binary signalling. The fourth chapter is concerned with some new and exciting results regarding the follower jammer paradigm. A counter-countermeasure technique is reviewed, notable for its counterintuitive characteristic which can be understood from a simple yet elegant game framework. The fifth chapter recounts some results pertaining to random coding for an optical spread spectrum link. The technique is based on laser speckle statistics and uses a coherent array of spatial light modulators at the transmitter but allows the receiver to be realized as a spatially distributed radiometric and therefore incoherent structure. The sixth and final chapter looks at an important and interesting application of spread spectrum to accurately locate a wideband, ‘bent pipe’, satellite transponder. It is, in a strong sense, an inverted GPS technique. Perspectives in Spread Spectrum serves as an excellent reference and source of ideas for further research, and may be used as a text for advanced courses on the topic.

This book provides a concise but lucid explanation of the fundamentals of spread-spectrum systems with an emphasis on theoretical principles. Throughout the book, learning is facilitated by many new or streamlined derivations of the classical theory. Problems at the end of each chapter are intended to assist readers in consolidating their knowledge and to provide practice in analytical techniques. The choice of specific topics is tempered by the author’s judgment of their practical significance and interest to both researchers and system designers. The evolution of spread spectrum communication systems and the prominence of new mathematical methods in their design provided the motivation to undertake this new edition of the book. This edition is intended to enable readers to understand the current state-of-the-art in this field. More than 20 percent of the material in this edition is new, including a chapter on systems with iterative channel estimation, and the remainder of the material has been thoroughly revised.

Agent-centric theories, approaches and technologies are contributing to enrich interactions between users and computers. This book aims at highlighting the influence of the agency perspective in Human-Computer Interaction through a careful selection of research contributions. Split into five sections; Users as Agents, Agents and Accessibility, Agents and Interactions, Agent-centric Paradigms and Approaches, and Collective Agents, the book covers a wealth of novel, original and fully updated material, offering: To provide a coherent, in depth, and timely material on the agency perspective in HCI To offer an authoritative treatment of the subject matter presented by carefully selected authors To offer a balanced and broad coverage of the subject area, including, human, organizational, social, as well as technological concerns. ü To offer a hands-on-experience by covering representative case studies and offering essential design guidelines The book will appeal to a broad audience of researchers and professionals associated to software engineering, interface design, accessibility, as well as agent-based interaction paradigms and technology.

RF CMOS Power Amplifiers: Theory Design and Implementation focuses on the design procedure and the testing issues of CMOS RF power amplifiers. This is the first monograph addressing RF CMOS power amplifier design for emerging wireless standards. The focus on power amplifiers for short is distance wireless personal and local area networks (PAN and LAN), however the design techniques are also applicable to emerging wide area networks (WAN) infrastructure using micro or pico cell networks. The book discusses CMOS power amplifier design principles and theory and describes the architectures and tardeoffs in designing linear and nonlinear power amplifiers. It then details design examples of RF CMOS power amplifiers for short distance wireless applications (e, g., Bluetooth, WLAN) including designs for multi-standard platforms. Design aspects of RF circuits in deep submicron CMOS are also discussed. RF CMOS Power Amplifiers: Theory Design and Implementation serves as a reference for RF IC design engineers and RD and R&D managers in industry, and for graduate students conducting research in wireless semiconductor IC design in general and with CMOS technology in particular.

Understanding the nature of random signals and noise is critically important for detecting signals and for reducing and minimizing the effects of noise in applications such as communications and control systems. Outlining a variety of techniques and explaining when and how to use them, Random Signals and Noise: A Mathematical Introduction focuses on applications and practical problem solving rather than probability theory. A Firm Foundation Before launching into the particulars of random signals and noise, the author outlines the elements of probability that are used throughout the book and includes an appendix on the relevant aspects of linear algebra. He offers a careful treatment of Lagrange multipliers and the Fourier transform, as well as the basics of stochastic processes, estimation, matched filtering, the Wiener-Khinchin theorem and its applications, the Schottky and Nyquist formulas, and physical sources of noise. Practical Tools for Modern Problems Along with these traditional topics, the book includes a chapter devoted to spread spectrum techniques. It also demonstrates the use of MATLAB® for solving complicated problems in a short amount of time while still building a sound knowledge of the underlying principles. A self-contained primer for solving real problems, Random Signals and Noise presents a complete set of tools and offers guidance on their effective application.

Global Perspective for Competitive Enterprise, Economy and Ecology addresses the general theme of the Concurrent Engineering (CE) 2009 Conference – the need for global advancements in the areas of competitive enterprise, economy and ecology. The proceedings contain 84 papers, which vary from the theoretical and conceptual to the practical and industrial. The content of this volume reflects the genuine variety of issues related to current CE methods and phenomena. Global Perspective for Competitive Enterprise, Economy and Ecology will therefore enable researchers, industry practitioners, postgraduate students and advanced undergraduates to build their own view of the inherent problems and methods in CE.