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Optical waveguides take a prominent role in photonics because they are able to trap and to transport light efficiently between a point of excitation and a point of detection. Moreover, waveguides allow the management of many of the fundamental properties of light and allow highly controlled interaction with other optical systems. For this reason waveguides are ubiquitous in telecommunications, sensing, spectroscopy, light sources, and high power light delivery. Nanostructured and subwavelength waveguides have additional advantages; they are able to confine light at a length scale below the diffraction limit and enhance or suppress light-matter interaction, as well as manage fundamental properties of light such as speed and direction of energy and phase propagation. This book presents semi-analytical theory and practical applications of a large number of subwavelength and nanostructured optical waveguides and fibers operating in various regions of the electromagnetic spectrum including visible, near and mid-IR and THz. A large number of approximate, while highly precise analytical expressions are derived that describe various modal properties of the planar and circular isotropic, anisotropic, and metamaterial waveguides and fibers, as well as surface waves propagating on planar, and circular interfaces. A variety of naturally occurring and artificial materials are also considered such as dielectrics, metals, polar materials, anisotropic all-dielectric and metal-dielectric metamaterials. Contents are organized around four major themes: Guidance properties of subwavelength waveguides and fibers made of homogeneous, generally anisotropic materials Guidance properties of nanostructured waveguides and fibers using both exact geometry modelling and effective medium approximation Development of the effective medium approximations for various 1D and 2D nanostructured materials and extension of these approximations to shorter wavelengths Practical applications of subwavelength and nanostructured waveguides and fibers Nanostructured Subwavelengths and Waveguides is unique in that it collects in a single place an extensive range of analytical solutions which are derived in various limits for many practically important and popular waveguide and fiber geometries and materials.

Recent developments such as the invention of powerful turbo-decoding and irregular designs, together with the increase in the number of potential applications to multimedia signal compression, have increased the importance of variable length coding (VLC). Providing insights into the very latest research, the authors examine the design of diverse near-capacity VLC codes in the context of wireless telecommunications. The book commences with an introduction to Information Theory, followed by a discussion of Regular as well as Irregular Variable Length Coding and their applications in joint source and channel coding. Near-capacity designs are created using Extrinsic Information Transfer (EXIT) chart analysis. The latest techniques are discussed, outlining radical concepts such as Genetic Algorithm (GA) aided construction of diverse VLC codes. The book concludes with two chapters on VLC-based space-time transceivers as well as on frequency-hopping assisted schemes, followed by suggestions for future work on the topic. Surveys the historic evolution and development of VLCs Discusses the very latest research into VLC codes Introduces the novel concept of Irregular VLCs and their application in joint-source and channel coding

In this book, Optical Wavelength Division Multiplexing (WDM) is approached from a strictly practical and application-oriented point of view. Based on the characteristics and constraints of modern fiber-optic components, transport systems and fibers, the text provides relevant rules of thumb and practical hints for technology selection, WDM system and link dimensioning, and also for network-related aspects such as wavelength assignment and resilience mechanisms. Actual 10/40 Gb/s WDM systems are considered, and a preview of the upcoming 100 Gb/s systems and technologies for even higher bit rates is given as well. Key features: Considers WDM from ULH backbone (big picture view) down to PON access (micro view). Includes all major telecom and datacom applications. Provides the relevant background for state-of-the-art and next-gen systems. Offers practical guidelines for system / link engineering.

During the last thirty years or so it has been widely recognised in the research community that the key transmission medium seeming capable of serving both the ever-growing demand for bandwidth and the unceasing need for new services, is optical fibre. In this context, Wavelength Division Multiplexing (WDM) is the most popular technique for introducing concurrency among multiple user transmissions into the network and, thus, exploiting the huge amount of fibre bandwidth available under the severe limitations imposed by electronics speed on the maximum network access rate. This book extensively covers an important research area in optical networking, enabling readers to fully understand the concepts of optical LANs and learn details of architecture issues and control protocols. Through its careful focus on the local area, the book, covers the major architectural, topological and protocol issues regarding optical Local Area Networks (LANs) today. Considering that constant advances on optical component technology make all-optical WDM LANs all the more feasible for a wide commercial deployment, the book investigates thoroughly the crucial latter topic, i.e. the Media-Access Control (MAC) protocols that should be used. Besides introducing a noteworthy part of the vast literature on such protocols and providing some helpful distinguishing key protocol characteristics, the book is also innovative in focusing on a recent significant class of promising protocols whose operation is based on network feedback information. In this way, these adaptive protocols for optical LANs achieve an overall higher performance in comparison with many other non-adaptive schemes. Multiwavelength Optical LANs: Enables readers to understand the concepts of optical LANs and learn details of architecture issues and control protocols Focuses on the major architectural, topological and protocol issues regarding optical local area networks Presents the important class of adaptive protocols for optical LANs No Optical systems/network developers, or engineers and scientists working in optical networking should be without this book. The well considered approach also makes this recommended reading for undergraduate and graduate computer science, computer, electrical and telecommunications engineering students.