Coherent Optical Wireless Communication Principle and Application


Book Description

This book presents the key technologies of coherent optical wireless communication, covers topics such as beam coupling, signal optical polarization control and distorted wavefront correction. It discusses the principle of coherent optical communication and heterodyne detection conditions. In this book, the array coupling receiving technology and large aperture coupling technology are introduced to realize the spatial optical fiber coupling; simulated annealing algorithm, particle swarm optimization algorithm and SPO algorithm are used to control the polarization state of the signal beam; and the correction of distorted wavefront of the signal beam by adaptive optics technology and wavefront sensorless adaptive optics technology are analyzed, and the influence of beam mode on coherent detection performance is elaborated. Both theoretical deduction and experimental results are included in this book, which can help readers further understand the theoretical knowledge.




Partially Coherent Optical Transmission Theory in Optical Wireless Communication


Book Description

This book introduces the theory and research methods of partially coherent optical, points out the significance of this study, analyzes the basic theories involved in partially coherent light, and explains the complete coherence of laser is not a necessary condition for good directivity, and partially spatially coherent optical sources can also produce the same far-field intensity distribution as lasers. This type of beam with good directivity but only partial spatial coherence is called a Gaussian Schell model beam, which can be used as a physical model to describe multimode lasers under certain conditions. This book is applicable to the large number of engineers and technicians involved in wireless optical communication and college teachers. It can also be used as a teaching material for graduate students and senior undergraduates in related fields.




Coherent Optical Fiber Communications


Book Description




Optical Wireless Communication


Book Description

The book gives a detailed description of optical wireless communication (OWC), including optical laser communication, visible light communication, ultraviolet communication, underwater optical communication and future communication technologies. To achieve an integration between theory and practice, the book avoids tedious mathematical deductions and includes theoretical materials as exercises. Most of the exercises are originated from published journal articles. These exercises will aid the readers in understanding the basic concept and methods and evaluating their knowledge acquisition in the field of OWC. The book is structured into Ten chapters that covers main aspects of OWC: - Optical wireless communication system - Coherent optical communication - Modulation, demodulation, and coding - Atmospheric channel, channel estimation, and channel equalization - White LED communication - Underwater laser communication - Ultraviolet communication - Acquisition, aiming, and tracking technology - Partially coherent optical transmission - Optical communication in the future The book is a suitable reference for undergraduate or postgraduate students majored in communication engineering, electronic information engineering or computer science, as well as the engineers and technicians in related fields.




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.




Short-Range Optical Wireless


Book Description

This book discusses the fundamental aspects of multiple-source Optical Wireless Applications, including Visible Light Communications (VLC). Moreover, the authors explore VLC performance in several conventional household layouts and investigate the impact of these layouts on VLC. Multiple sources increase multipath distortion. Multi-input- Multi-Output (MIMO) techniques will be included as they provide either reliability improvement or bandwidth efficiency increase. Based on these topics, the book further explores VLC performance in real applications, such as aircraft cabin wireless communications. In addition, the authors describe the Lambertian emitting pattern of LEDs and the diffused features in indoor environments. Based on the theory, they trace light pulses to establish a MIMO indoor wireless channel model on specific sources layout. Next, they generate test data to simulate BER distribution in a room and calculate the outage. Furthermore, addresses the performance improvement when MIMO techniques are applied. Lastly, the authors investigate VLC performance in specific applications, including for aircraft on-board wireless communications. Finally, the pitfalls of MIMO systems are discussed.




Optical Fiber Telecommunications VIB


Book Description

In this chapter, we present an overview of multicarrier transmission and its application to optical communication. Specifically, we first introduce the historical perspectives in the development of optical multicarrier technologies. We then present different variants of optical multicarrier transmission. We also highlight the problem of fiber nonlinearity in optical multicarrier transmission systems and present an analysis of fiber capacity under nonlinear impairments. Furthermore, we discuss applications of multicarrier techniques to long-haul systems, access networks, and free-space optical communication systems. Finally, we summarize with some possible research directions in implementing multicarrier technologies in optical transmission.




Digital Processing


Book Description

With coherent mixing in the optical domain and processing in the digital domain, advanced receiving techniques employing ultra-high speed sampling rates have progressed tremendously over the last few years. These advances have brought coherent reception systems for lightwave-carried information to the next stage, resulting in ultra-high capacity global internetworking. Digital Processing: Optical Transmission and Coherent Receiving Techniques describes modern coherent receiving techniques for optical transmission and aspects of modern digital optical communications in the most basic lines. The book includes simplified descriptions of modulation techniques for such digital transmission systems carried by light waves. It discusses the basic aspects of modern digital optical communications in the most basic lines. In addition, the book covers digital processing techniques and basic algorithms to compensate for impairments and carrier recovery, as well as noise models, analysis, and transmission system performance.




Optical Communications


Book Description

This book focuses on recent research and developments on optical communications. The chapters present different aspects of optical communication systems, comprising high capacity transmission over long distances, coherent and intensity modulated technologies, orthogonal frequency-division multiplexing, ultrafast switching techniques, and photonic integrated devices. Digital signal processing and error correction techniques are also addressed. The content is of interest to graduate students and researchers in optical communications.




Space-Division Multiplexing in Optical Communication Systems


Book Description

This book presents new frontiers in data communication. To transcend the physical limitations of current optical communication technologies, totally new multiplexing schemes beyond TDM/WDM, novel transmission optical fibers handling well above Pbit/s capacity, and next-generation optical submarine cable systems will need to be developed. The book offers researchers working at the forefront, as well as advanced Ph.D. students in the area of optical fiber communications systems and related fields, an essential guide to state-of-the-art optical transmission technologies. It explores promising new technologies for the exabit era; namely, the three “M technologies”: multi-level modulation, multi-core fiber, and multi-mode control.