Spread-spectrum communication is a core area within the field of DIGITAL communication. Originally used in military networks as countermeasures against the threats of jamming and interception, spread-spectrum systems are now widely used in commercial applications and are part of several wireless and mobile communication standards. Although spread-spectrum communication is a staple topic in textbooks on DIGITAL communication, its treatment is usually cursory. This book is designed to provide a more intensive examination of the subject that is suitable for graduate students and practicing engineers with a solid background in the theory of DIGITAL communication. As the title indicates, this book stresses principles rather than specific current or planned systems, which are described in manyotherbooks.My goal in this bookis to providea concisebut lucidexplanation of the fundamentals of spread-spectrum systems with an emphasis on theoretical principles.
标签： Spread-Spectrum Communication Systems 2nd
上传时间： 2020-06-01
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In Helsinki during a visiting lecture, an internationally well-known professor in communica- tionssaid,‘Inthecommunicationssocietywehavemanagedtoconvertourproposalsandideas to real products, not like in the control engineering society. They have very nice papers and strong mathematics but most of the real systems still use the old PID controllers!’. As our background is mainly in control as well as communications engineering, we know that this thought is not very accurate. We agree that most of the practical controllers are analog and DIGITAL PID controllers, simply because they are very reliable and able to achieve the required control goals successfully. Most of the controllers can be explained in terms of PID. The reasons behind this impressive performance of PID will be explained in Chapter 2.
标签： Communications Engineering Wireless Systems in
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Intensive development of DIGITAL technologies coincided in time with the beginning of the new era in telecommunications. It made possible to formalize many proce- dures of data exchange and to atomize some operations which made providing of serviceandmakeworkofmanytelecommunicationworkersmucheasier. Somenew telecommunication technologies were born out of the necessity for use of specific configurations of network elements and networks, as well as for a possibility of providing maximum characteristics of efficiency combined with high requirements to the stability of operation, the overcoming of different catastrophic situations and deadlockconditions,such as failuresand ”pending”of the networkandthe like. The thresholdbetweeninformationsystems andtelecommunicationsystems has become practically invisible. It resulted in such a new term as ”infocommunication”
上传时间： 2020-06-01
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Rapid progress in information and communications technology (ICT) induces improved and new telecommunications services and contributes greatly to society in general and to vendors and network and service providers. In addition to existing services such as telephony or leased line services, spread of the Internet, the Internet Protocol (IP) phone, and new communications services like IPTV are making great progress with the development of DIGITAL subscriber lines (DSL) and high - speed communications technologies like fi ber to the home (FTTH).
标签： Telecommunications Networks
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Wireless communication has become increasingly important not only for professional appli- cations but also for many fields in our daily routine and in consumer electronics. In 1990, a mobile telephone was still quite expensive, whereas today most teenagers have one, and they use it not only for calls but also for data transmission. More and more computers use wireless local area networks (WLANs), and audio and television broadcasting has become DIGITAL.
标签： Applications and Theory OFDM CDMA of
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Wireless communications has become a field of enormous scientific and economic interest. Recent success stories include 2G and 3G cellular voice and data services (e.g., GSM and UMTS), wireless local area networks (WiFi/IEEE 802.11x), wireless broadband access (WiMAX/IEEE 802.16x), and DIGITAL broadcast systems (DVB, DAB, DRM). On the physical layer side, traditional designs typically assume that the radio channel remains constant for the duration of a data block. However, researchers and system designers are increasingly shifting their attention to channels that may vary within a block. In addition to time dispersion caused by multipath propagation, these rapidly time-varying channels feature frequency dispersion resulting from the Doppler effect. They are, thus, often referred to as being “doubly dispersive.”
标签： Time-Varying Channels
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T his book covers basic communications theory and practical imple- mentation of transmitters and receivers. In so doing, I focus on dig- ital modulation, demodulation methods, probabilities, detection of DIGITAL signals, and spread spectrum system design and analysis. This book was written for those who want a good understanding of the basic prin- ciples of DIGITAL wireless communication systems, including spread spec- trum techniques. This book also provides a good intuitive and practical approach to DIGITAL communications. Therefore it is a valuable resource for anyoneinvolvedinwirelesscommunicationsandtransceiverdesignfordig- ital communications. The reader will gain a broad understanding of basic communication principles for transceiver design, DIGITAL communications, and spread spectrum, along with examples of many types of commercial and military data link systems.
标签： Transceiver System Design
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Wireless networking is undergoing a transformation from what has been primarily a medium for supporting voice traffic between telephones, into what is increasingly becoming a medium for supporting traffic among a variety of DIGITAL devices transmitting media of many types (voice, data, images, video. etc.) Wireline networking underwent a similar transformation in the 1990s, which led to an enormous build-up in the capacity of such networks, primarily through the addition of new optical fiber, switches and other infrastructure.
标签： Multiusers Detection Wireless Networks
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DIGITAL radios have undergone an astonishing evolution in the last century. Born as a set of simple and power-hungry electrical and electromechanical devices for low data rate transmission of telegraph data in the Marconi age, they have transformed, thanks to substantial advances in electronic technology, into a set of small, reliable and sophisticated integrated devices supporting broadband multimedia communications. This, however, would not have been possible unless significant progress had been made in recent decades in the field of signal processing algorithms for baseband and passband signals. In fact, the core of any modern DIGITAL radio consists of a set of algorithms running over programmable electronic hardware. This book stems from the research and teaching activities of its co-authors in the field of algorithmic techniques for wireless communications. A huge body of technical literature has accumulated in the last four decades in this area, and an extensive coverage of all its important aspects in a single textbook is impossible. For this reason, we have selected a few important topics and, for ease of reading, organized them into two parts.
标签： Communications Algorithmic Techniques Wireless
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It has been said that the move from narrowband to broadband access is the second revolution for the Internet — ‘broadband is more bandwidth than you can use’. Once users have experienced broadband access there is no turning back. A whole new world of applications and services becomes possible. No longer is it the ‘world- wide wait’. The speed of response and visual quality enabled by broadband finally allows the Internet to reach its true potential.
上传时间： 2020-06-06
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