This book discusses the problems of  Physical Layer Security (PLS) in Intelligent Reflecting Surface (IRS)-assisted wireless networks. It also discusses the corresponding methods to solve these problems in a comprehensive style.  Furthermore, some potential challenges are well analyzed. This book is divided into 11 chapters.  Chapter 1 introduces the propagation characteristics of IRS-aided PLS communications. From Chapter 2 to Chapter 10, The authors mainly provide deep investigations of different PLS problems of  IRS-aided wireless networks, namely, directional modulation (DM) networks. Chapter 11 draws a conclusion and includes the future research directions. Researchers working in wireless communications, or advanced-level computer science or electrical engineering students, can learn about secure communication in the physical layer through our book. Professionals or engineers working in this field will also benefit from this book.

Distributed MIMO and cell-free mobile communication are emerging technologies of wireless communication. This book introduces the fundamental theory, key technology and the prototype system of distributed MIMO and cellular free mobile communication system, including the unified system model, capacity and spectral efficiency analysis under imperfect channel information, cell edge effect, optimal power allocation and energy efficiency optimization, cache optimization, low complexity wireless transmission technology and new network assisted full duplex technology. In addition, the implementation of software and hardware and test results of distributed MIMO and cell free system based on cloud architecture are introduced in detail.This book will benefit senior undergraduates, postgraduates, scholars and engineers who are engaged in wireless mobile communication research. It can also be used as a reference book for postgraduates and researchers in the field of electronic and information engineering.

Distributed MIMO and cell-free mobile communication are emerging technologies of wireless communication. This book introduces the fundamental theory, key technology and the prototype system of distributed MIMO and cellular free mobile communication system, including the unified system model, capacity and spectral efficiency analysis under imperfect channel information, cell edge effect, optimal power allocation and energy efficiency optimization, cache optimization, low complexity wireless transmission technology and new network assisted full duplex technology. In addition, the implementation of software and hardware and test results of distributed MIMO and cell free system based on cloud architecture are introduced in detail.This book will benefit senior undergraduates, postgraduates, scholars and engineers who are engaged in wireless mobile communication research. It can also be used as a reference book for postgraduates and researchers in the field of electronic and information engineering.

The broadband wireless communications field is growing at an explosive rate, stimulated by a host of important emerging applications ranging from 3G, 4G and wireless LAN. Wideband CDMA and CDMA2000 will be used for 3G. OFDM+CDMA might be a good choice for 4G, CDMA overlay will possibly be used for new-generation broadband wireless LAN. For system planners and designers, the projections of rapidly escalating demand for such wireless services present major challenges and meeting these challenges will require sustained technical innovation on many fronts. The text of this book has been developed through years of research by the author and his graduate students at the University of Hong Kong. The aim of this book is to provide a R&D perspective on the field of broadband wireless communications by describing the recent research developments in this area and also by identifying key directions in which further research is needed. As a background, I presume that the reader has a thorough understanding of digital communications and spread spectrum/CDMA. The book is arranged into 13 chapters. In chapter 1, some key specifications of 3G WCDMA are described and discussed. These techniques include channel coding, rate matching, modulation and spreading, power control, cell search, transmit diversity, soft-handoff, and so son. In Chapter 2, the coherent RAKE reception of Wideband CDMA signals with complex spreading is considered. A dedicated pilot channel, which is separate from data channels, is used for the purpose of channel estimation.

The broadband wireless communications field is growing at an explosive rate, stimulated by a host of important emerging applications ranging from 3G, 4G and wireless LAN. Wideband CDMA and CDMA2000 will be used for 3G. OFDM+CDMA might be a good choice for 4G, CDMA overlay will possibly be used for new-generation broadband wireless LAN. For system planners and designers, the projections of rapidly escalating demand for such wireless services present major challenges and meeting these challenges will require sustained technical innovation on many fronts. The text of this book has been developed through years of research by the author and his graduate students at the University of Hong Kong. The aim of this book is to provide a R&D perspective on the field of broadband wireless communications by describing the recent research developments in this area and also by identifying key directions in which further research is needed. As a background, I presume that the reader has a thorough understanding of digital communications and spread spectrum/CDMA. The book is arranged into 13 chapters. In chapter 1, some key specifications of 3G WCDMA are described and discussed. These techniques include channel coding, rate matching, modulation and spreading, power control, cell search, transmit diversity, soft-handoff, and so son. In Chapter 2, the coherent RAKE reception of Wideband CDMA signals with complex spreading is considered. A dedicated pilot channel, which is separate from data channels, is used for the purpose of channel estimation.

Analysing and designing reliable and fast wireless networks requires an understanding of the theory underpinning these systems and the engineering complexities of their implementation. This text describes the underlying principles and major applications of high-speed wireless technologies, with emphasis on ultra-wideband (UWB) wireless systems, 3G long term evolution, and 4G mobile networks. Key topics such as cross-layer optimization are discussed in detail and various forms of UWB, including multi-band OFDM UWB, are covered. Recent research developments are described before identifying the scope and direction for future research. The overlay problem (interference problem) in UWB is discussed, and the author aims to illustrate that OFDM is not the best wireless access technique for high speed transmission. Covering the latest technologies in the area, this book will be a valuable resource for graduate students of electrical and computer engineering as well as practitioners in the wireless communications industry.