Xizheng Ke – författare

This book introduces in detail the theory of adaptive optics and its correction technology for light wave distortion in wireless optical communication. It discusses the adaptive control algorithm of wavefront distortion, proportional+integral control algorithm and iterative control algorithm, and double fuzzy adaptive PID control algorithm. It also covers the SPGD algorithm of adaptive optics correction, deformable mirrors eigenmode method of wavefront aberration correction, vortex beam wavefront detecting wavefront aberration correction, liquid crystal spatial light modulator wavefront correction, different wavelengths of Gaussian beam transmission wavefront differences in the atmospheric turbulence and correction and with wavefront tilt correction adaptive optics wavefront aberration correction. Various distortion correction methods are verified by experiments and the experimental results are analyzed.

This book is suitable for engineering and technicalpersonnel engaged in wireless optical communication, college teachers, graduate students and senior undergraduate students.

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.

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.

This book presents some of the recent developments in the field of optical-wireless coherence communication. The factors affecting the coherence detection sensitivity are analyzed and the approach to approximate the coherence detection limit is discussed. The wavefront distortion caused by atmospheric turbulence is analyzed, and the influence of the wavefront distortion on the coherence detection performance is examined. A new concept of vortex-beam coherence-detection is proposed, and the problem of signal light decomposition into partially coherent light detection is analyzed. This book can benefit researchers, engineers, and graduate students in the field of telecommunications. It is suitable for engineering and technical personnel engaged in applied optics and communications engineering, university teachers, graduate students, and senior undergraduates.

The book focuses on optical wireless communication systems. It summarises the author''s work on optical wireless communication during the implementation of relevant scientific research plans. The main contents include the research status and progress of optical wireless communication, including the author''s own work in this field and the research progress of domestic and foreign scholars in related fields. The key technologies, key components, modulation and coding methods, influencing factors of coherent optical communication, underwater optical communication, visible light communication, and orbital angular momentum involved in wireless optical communication are analysed, and their research progress and development trends are presented. It is particularly suitable for readers interested in the field of wireless optical communications. This book can benefit researchers, engineers and graduate students in the field of telecommunications. Suitable for engineering and technical personnel involved in optical communications, university teachers, postgraduate students and advanced undergraduates.

This book is divided into 12 chapters, including introduction, multi-aperture transmit/receive technology in turbulent atmosphere, channel model and channel capacity, orthogonal space-time block coding, layered space-time coding, hybrid space-time coding, space-time trellis coding, differential space-time coding, unitary space-time coding, adaptive layered space-time coding, performance analysis of indoor MIMO-VLC system, and detection algorithm of MIMO technology. The key technologies of wireless optical MIMO systems are introduced, and the basic framework of space-time coding of wireless optical MIMO systems is proposed.

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.

The book focuses on noise models in optical-wireless communication systems. The main contents include noise classification in optical-wireless communication systems, as well as the current research progress at home and abroad, explores the noise mechanism in optical-wireless communication systems, as well as the establishment of a noise model and analysis methods to suppress the noise of optical-wireless communication systems. Combining theory with practice, systematic analysis of all kinds of noise in optical-wireless communication system, so that readers have a comprehensive understanding of the noise in optical-wireless communication system, which is an important feature of this book. The book can benefit senior college students in electronic information, communication engineering, and applied optical majors, as well as graduates, engineers, and technical personnel, etc.