Modulation and Coding Techniques in Wireless Communications


Book Description

The high level of technical detail included in standards specifications can make it difficult to find the correlation between the standard specifications and the theoretical results. This book aims to cover both of these elements to give accessible information and support to readers. It explains the current and future trends on communication theory and shows how these developments are implemented in contemporary wireless communication standards. Examining modulation, coding and multiple access techniques, the book is divided into two major sections to cover these functions. The two-stage approach first treats the basics of modulation and coding theory before highlighting how these concepts are defined and implemented in modern wireless communication systems. Part 1 is devoted to the presentation of main L1 procedures and methods including modulation, coding, channel equalization and multiple access techniques. In Part 2, the uses of these procedures and methods in the wide range of wireless communication standards including WLAN, WiMax, WCDMA, HSPA, LTE and cdma2000 are considered. An essential study of the implementation of modulation and coding techniques in modern standards of wireless communication Bridges the gap between the modulation coding theory and the wireless communications standards material Divided into two parts to systematically tackle the topic - the first part develops techniques which are then applied and tailored to real world systems in the second part Covers special aspects of coding theory and how these can be effectively applied to improve the performance of wireless communications systems




Modulation and Constrained Coding Techniques for Wireless Infrared Communication Channels


Book Description

Short-distance, point-to-point wireless infrared optical links provide a cost-effective means of high speed data transfer between portable devices. To investigate such links, a test-bench and circuits were constructed to determine the limitations of existing optoelectronics. The results of these measurements we used to formulate a signal-space channel model which is employed for the subsequent analysis of candidate bandwidth efficient modulation schemes. The modulation scheme Adaptively Biased QAM (AB-QAM) is developed based on the channel model. AB-QAM provides an asymptotic 3 dB optical SNR improvement over PAM while maintaining the same bandwidth efficiency. The use of constellation shaping is shown to further improve the average optical power efficiency of AB-QAM. This thesis proposes the use of constrained coding techniques to satisfy the non-negativity constraint of the optical channel. These coding techniques are illustrated through an example and contrasted to a baseline case. Constrained coding techniques allow greater flexibility in the choice of pulse shapes used in the channel, leading to possible optical power and bandwidth gains.







Modulation and Coding


Book Description

Preface. Abbreviations. 1. Introduction to modulation and coding. 2. Principles of linear modulation. 3. Modulation for non-linear systems. 4. Modem design. 5. Principles of FEC Coding. 6. Cyclic block codes. 7. Convolutionals codes. 8. Coded modulation. 9. Modulation and coding on multipath channels. 10. OFDM. 11. Turbo-codes. Appendix 1. Finite field theory. Appendix 2. The MAP algorithm.




Optical Code Division Multiple Access


Book Description

Code-division multiple access (CDMA) technology has been widely adopted in cell phones. Its astonishing success has led many to evaluate the promise of this technology for optical networks. This field has come to be known as Optical CDMA (OCDMA). Surveying the field from its infancy to the current state, Optical Code Division Multiple Access: Fundamentals and Applications offers the first comprehensive treatment of OCDMA from technology to systems. The book opens with a historical perspective, demonstrating the growth and development of the technologies that would eventually evolve into today's optical networks. Building on this background, the discussion moves to coherent and incoherent optical CDMA coding techniques and performance analysis of these codes in fiber optic transmission systems. Individual chapters provide detailed examinations of fiber Bragg grating (FBG) technology including theory, design, and applications; coherent OCDMA systems; and incoherent OCDMA systems. Turning to implementation, the book includes hybrid multiplexing techniques along with system examples and conversion techniques to connect networks that use different multiplexing platforms, state-of-the-art integration technologies, OCDMA network security issues, and OCDMA network architectures and applications, including a look at possible future directions. Featuring contributions from a team of international experts led by a pioneer in optical technology, Optical Code Division Multiple Access: Fundamentals and Applications places the concepts, techniques, and technologies in clear focus for anyone working to build next-generation optical networks.




Advanced Optical Wireless Communication Systems


Book Description

Combines theory with real-world case studies to give a comprehensive overview of modern optical wireless technology.




Low-Power Wireless Infrared Communications


Book Description

Today, wireless infrared transmission has entered our homes, offices, industry and health care, with applications in the field of remote control, telemetry, and local communication. This book is about the underlying technology. As it is an outgrowth of my Ph.D. thesis, the emphasis is on fundamental aspects rather than industrial aspects, like the standardization effort by the IrDA [7]. I guess that this is not a drawback, as, eventually, the laws of physics apply to all of us! As the applied radiation is not necessarily in the infrared, throughout the book we usually prefer the term optical transmission. As most equipment is battery-powered, the emphasis is on power optimiza tion of the optical transmission system. System parameters as well as environ mental parameters that determine the eventual transmission quality are iden tified, to facilitate well-reasoned system design. Many design rules, based on calculations, measurements and simulations are presented to help the designer push the performance close to the limits set by nature and the available tech nology. The first chapters introduce the subject and the present the scope of the book. Then, the basic transmission link is introduced in chapter 3, and strate gies to optimize its signal-to-noise ratio are discussed. Lighting flicker is identi fied as a possible source of interference. Then, receiver noise and bandwidth are discussed in chapter 4, mainly based on the material presented in [66], [67], [69].




Advanced Optical and Wireless Communications Systems


Book Description

The new edition of this popular textbook keeps its structure, introducing the advanced topics of: (i) wireless communications, (ii) free-space optical (FSO) communications, (iii) indoor optical wireless (IR) communications, and (iv) fiber-optics communications, but thoroughly updates the content for new technologies and practical applications. The author presents fundamental concepts, such as propagation principles, modulation formats, channel coding, diversity principles, MIMO signal processing, multicarrier modulation, equalization, adaptive modulation and coding, detection principles, and software defined transmission, first describing them and then following up with a detailed look at each particular system. The book is self-contained and structured to provide straightforward guidance to readers looking to capture fundamentals and gain theoretical and practical knowledge about wireless communications, free-space optical communications, and fiber-optics communications, all which can be readily applied in studies, research, and practical applications. The textbook is intended for an upper undergraduate or graduate level courses in fiber-optics communication, wireless communication, and free-space optical communication problems, an appendix with all background material needed, and homework problems. In the second edition, in addition to the existing chapters being updated and problems being inserted, one new chapter has been added, related to the physical-layer security thus covering both security and reliability issues. New material on 5G and 6G technologies has been added in corresponding chapters.