Optical Communication Theory and Techniques


Book Description

Since the advent of optical communications, a greattechnological effort has been devoted to the exploitation of the huge bandwidth of optical fibers. Sta- ing from a few Mb/s single channel systems, a fast and constant technological development has led to the actual 10 Gb/s per channel dense wavelength - vision multiplexing (DWDM) systems, with dozens of channels on a single fiber. Transmitters and receivers are now ready for 40 Gb/s, whereas hundreds of channels can be simultaneously amplified by optical amplifiers. Nevertheless, despite such a pace in technological progress, optical c- munications are still in a primitive stage if compared, for instance, to radio communications: the widely spread on-off keying (OOK) modulation format is equivalent to the rough amplitude modulation (AM) format, whereas the DWDM technique is nothing more than the optical version of the frequency - vision multiplexing (FDM) technique. Moreover, adaptive equalization, ch- nel coding or maximum likelihood detection are still considered something “exotic” in the optical world. This is mainly due to the favourable char- teristics of the fiber optic channel (large bandwidth, low attenuation, channel stability, ...), which so far allowed us to use very simple transmission and detection techniques.




Coding for Optical Channels


Book Description

In order to adapt to the ever-increasing demands of telecommunication needs, today’s network operators are implementing 100 Gb/s per dense wavelength division multiplexing (DWDM) channel transmission. At those data rates, the performance of fiberoptic communication systems is degraded significantly due to intra- and inter-channel fiber nonlinearities, polarization-mode dispersion (PMD), and chromatic dispersion. In order to deal with those channel impairments, novel advanced techniques in modulation and detection, coding and signal processing are needed. This unique book represents a coherent and comprehensive introduction to the fundamentals of optical communications, signal processing and coding for optical channels. It is the first to integrate the fundamentals of coding theory with the fundamentals of optical communication.




Advanced Optical Communication Systems and Networks


Book Description

This resource provides the latest details on 5th generation photonic systems that can be readily applied to projects in the field. Moreover, the book provides valuable, time-saving tools for network simulation and modeling. It includes coverage of optical signal transmission systems and networks; a wide range of critical methods and techniques, such as MIMO (multiple-input and multiple-output) by employing spatial modes in few-mode and multicore optical fiber; OFDM (orthogonal frequency-division multiplexing) utilized to enhance the spectral efficiency and to enable elastic optical networking schemes; and advanced modulation and coding schemes to approach the Shannon's channel capacity limit. There are detailed discussions on the basic principles and applications of high-speed digital signal processing, as well as description of the most relevant post-detection compensation techniques




Optical Fiber Telecommunications VIB


Book Description

This chapter represents an overview of advanced coding techniques for optical communication. Topics include: codes on graphs, coded modulation, rate-adaptive coded modulation, and turbo equalization. The main objectives of this chapter are: (i) to describe different classes of codes on graphs of interest for optical communications, (ii) to describe how to combine multilevel modulation and channel coding, (iii) to describe how to perform equalization and soft-decoding jointly, and (iv) to demonstrate efficiency of joint de-modulation, decoding, and equalization in dealing with various channel impairments simultaneously. Codes on graphs of interest for next-generation FEC for high-speed optical transport include turbo codes, turbo-product codes and low-density parity-check (LDPC) codes. We describe both binary and nonbinary LDPC codes, their design and decoding algorithms. We also discuss an FPGA implementation of decoders for binary LDPC codes. We demonstrate that an LDPC-coded turbo equalizer is an excellent candidate to simultaneously mitigate uncompensated chromatic dispersion, PMD, fiber nonlinearities and I/Q-imbalance. For completeness of presentation, we also provide the information capacity study of optical channels with memory.




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







Wireless Optical Communication Systems


Book Description

This volume addresses the problem of designing efficient signalling and provides a link between the areas of communication theory and modem design for amplitude constrained linear optical intensity channel. It provides practical guidelines for the design of signalling sets for wireless optical intensity channels.







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.