Tho Le-Ngoc – författare

Learn about Ultra-wideband (UWB) transmission - the most talked about application in wireless communications. UWB wireless communication is a revolutionary technology for transmitting large amounts of digital data over a wide spectrum of frequency bands with very low power for a short distance. This exciting new text covers the fundamental aspects of UWB wireless communications systems for short-range communications. It also focuses on more advanced information about networks and applications. Chapters include: Radio Propagation and Large Scale Variations, Pulse Propagation and Channel Modelling, MIMO (Multiple Input, Multiple Output) RF Subsystems and Ad Hoc Networks. Focuses on UWB wireless communications rather than UWB radar, which has been covered before.Provides long and short-term academic and technological value.Teaches readers the fundamentals, challenges and up-to-date technical processes in this field.

"Coded-Modulation Techniques for Fading Channels" provides the reader with a sound background for the application of bandwidth-efficient coded-modulation techniques in fading channels. The book systematically presents recent developments in the field, which has grown rapidly in recent years, and provides a solid frame of reference for further research in this area. During the past decade there has been a proliferation of research in the area of bandwidth-efficient coded-modulation techniques. The primary advantage of these schemes over modulation schemes employing traditional error-correcting codes is their ability to improve the performance of the communicaton system without bandwidth expansion. This property makes them a suitable choice for channels which are limited in both power and bandwidth. A typical example of such channels is a mobile satellite channel, where it is desired to accommodate a large number of users in a given bandwidth with a power which is constrained by the physical size of the satellite and by the vehicle's antenna. The text should be a useful reference for researchers and practising engineers, and may be used as a text for advanced courses on the subject.

Coded-Modulation Techniques for Fading Channels provides the reader with a sound background for the application of bandwidth-efficient coded-modulation techniques in fading channels. The book systematically presents recent developments in the field, which has grown rapidly in recent years, and provides a solid frame of reference for further research in this area. During the past decade there has been a proliferation of research in the area of bandwidth-efficient coded-modulation techniques. The primary advantage of these schemes over modulation schemes employing traditional error correcting codes is their ability to improve the performance of the communication system without bandwidth expansion. This property makes them a suitable choice for channels which are limited in both power and bandwidth. A typical example of such channels is a mobile satellite channel, where it is desired to accommodate a large number of users in a given bandwidth with a power which is constrained by the physical size of the satellite and by the vehicle's antenna. Coded-Modulation Techniques for Fading Channels is an excellent reference for researchers and practicing engineers, and may be used as a text for advanced courses on the subject.

This book covers the design and optimization of hybrid RF-baseband precoding for massive multiple-input multiple-output (MIMO)-enabled cloud radio access networks (RANs), where use cases such as millimeter-wave wireless backhauling, fully-loaded cellular networks are of interest. The suitability and practical implementation of the proposed precoding solutions for the Cloud RAN architecture are also discussed.Novel techniques are examined for RF precoding optimization in combination with nonlinear precoding at baseband, and the superiority of joint RF-baseband design is verified. Moreover, the efficacy of hybrid RF-baseband precoding to combat intercell interference in a multi-cell environment with universal frequency reuse is investigated, which is concluded to be a promising enabler for the dense deployment of base stations.This book mainly targets researchers and engineers interested in the challenges, optimization, andimplementation of massive MIMO precoding in 5G Cloud RAN. Graduate students in electrical engineering and computer science interested in the application of mathematical optimization to model and solve precoding problems in massive MIMO cellular systems will also be interested in this book.

This book assists readers with understanding the key aspects, problems and solutions related to the design of proper Multiple Access Schemes for MTC (Machine-Type Communications) and IoT applications in 5G-and-beyond wireless networks.

This book assists readers with understanding the key aspects, problems and solutions related to the design of proper Multiple Access Schemes for MTC (Machine-Type Communications) and IoT applications in 5G-and-beyond wireless networks.

The authors explore various Unmanned Aerial Vehicle (UAV)-assisted massive Multiple-Input and Multiple-Output (MIMO) relaying systems designed for 5G-and-Beyond wireless networks.  This book also addresses scenarios where a direct connection between a base station and users is blocked, and a UAV acts as a relay to ensure seamless connectivity. The goal is to maximize the total achievable rate by solving key optimization problems in UAV placement, power allocation, and beamforming design. To tackle these challenges, the authors present novel artificial intelligence (AI)-driven solutions that achieve near-optimal performance in complex environments.The first part introduces particle swarm optimization (PSO), a nature-inspired algorithm, for both single-user and multi-user massive MIMO settings, extending to multiple-UAV relay configurations. Our results demonstrate that PSO-based approaches can effectively enhance network capacity and coverage.  The second part focuses on reducing computational complexity, while maintaining high performance. The authors develop deep learning (DL)-based approaches, from supervised learning for UAV placement and power allocation to deep reinforcement learning for trajectory optimization in dynamic conditions. Numerical evaluations confirm that these DL-based methods achieve reduced runtime without sacrificing achievable rates.This book targets researchers, advanced-level students and engineers interested in the challenges and practical solutions for UAV-assisted MIMO communications in  wireless networks. Professionals working in wireless communications focused on this topic will also want to purchase this book.

This book presents an integrated study of metamaterial-based large-scale antenna arrays and beamforming optimization for both Half-Duplex (HD) and Full-Duplex (FD) massive MIMO (mMIMO) systems. As a cornerstone of future wireless communications, mMIMO provides substantial improvements in capacity and spectral efficiency, which this book illustrates. With strategically designed beamforming, these arrays can precisely direct energy toward intended users, while effectively suppressing interference. Metamaterial structures with tunable electromagnetic properties further enhance performance by enabling compact, high-isolation antenna elements and novel interference mitigation strategies. In addition, hybrid beamforming architectures are investigated to achieve an optimal balance between system performance and hardware complexity.The first part of this book focuses on HD MU-mMIMO. Various planar and non-planar array structures are studied through full-wave simulations and prototype measurements, considering user distributions and hardware non-idealities. Novel nulling beamforming algorithms are developed, targeting both Far-Field angular separation and Near-Field spatially separated users. Deep, precisely aligned nulls are created to effectively suppress multi-user interference to noise levels, while preserving desired signal strength.  The second part addresses FD mMIMO, where concurrent transmission and reception promise doubled spectral efficiency, but demand strong self-interference (SI) suppression. A multi-stage transmit–receive isolation framework is introduced, integrating antenna isolation, joint beamforming, and metamaterial absorber structures. By combining beam-level isolation with cancellation techniques, experimental measurements demonstrate that residual SI can be suppressed to the noise floor, thereby ensuring reliable FD mMIMO performance.This book is intended for researchers, engineers and advanced-level students focused on advanced wireless systems, antenna innovations, and 5G-and-beyond technology development.  It is especially valuable to R&D professionals in telecommunications companies, RF/microwave design firms, or labs working on next-generation wireless networks, antennas, and full-duplex solutions. The content provides both theoretical foundations and practical design considerations for mMIMO, full-duplex architectures, and metamaterial-based antennas. It also caters to specialists in electrical engineering, wireless communications, antenna/RF design, or signal processing who seek an in-depth exploration of cutting-edge multi-antenna technologies.

This SpringerBriefs is an overview of the emerging field of wireless access and mobile network virtualization. It provides a clear and relevant picture of the current virtualization trends in wireless technologies by summarizing and comparing different architectures, techniques and technologies applicable to a future virtualized wireless network infrastructure. The readers are exposed to a short walkthrough of the future Internet initiative and network virtualization technologies in order to understand the potential role of wireless virtualization in the broader context of next-generation ubiquitous networks. Three main wireless virtualization perspectives are explored, along with the potential challenges and requirements of a sustainable wireless virtualization framework. Finally, it presents an example of a multi-perspective wireless virtualization framework. The readers learn the latest concepts in the application of wireless virtualization as well as its relationship with cutting-edge wireless technologies such as software-defined radio (SDR) and cognitive radio.

This Springer Brief presents the architectures of small-cell networks and recent advances in interference management. The key challenges and values of small cells are first introduced, followed by the reviews of various small-cell architectures and interference management techniques in both heterogeneous CDMA and heterogeneous OFDMA small-cell networks. New adaptive power control and dynamic spectrum access techniques are discussed to promote a harmonized coexistence of diverse network entities in both 3G and 4G small-cell networks. Analytically devised from optimization and game theories, autonomous solutions are shown to effectively manage the intra-tier and cross-tier interferences in small cells. Informative and practical, this Springer Brief is designed for researchers and professionals working in networking and resource management. The content is also valuable for advanced-level students interested in network communications and power allocation.

This SpringerBrief discusses the current research on coordinated multipoint transmission/reception (CoMP) in wireless multi-cell systems. This book analyzes the structure of the CoMP precoders and the message exchange mechanism in the CoMP system in order to reveal the advantage of CoMP. Topics include interference management in wireless cellular networks, joint signal processing, interference coordination, uplink and downlink precoding and system models. After an exploration of the motivations and concepts of CoMP, the authors present the architectures of a CoMP system. Practical implementation and operational challenges of CoMP are discussed in detail. Also included is a review of CoMP architectures and deployment scenarios in the LTE-Advanced standard. Readers are exposed to the latest multiuser precoding designs for the CoMP system under two operating modes, interference aware and interference coordination. Wireless Coordinated Multi cell Systems: Architectures and Precoding Designs is a concise and approachable tool for researchers, professionals and advanced-level students interested in wireless communications and networks.

This brief presents a comprehensive review of the network architecture and communication technologies of the smart grid communication network (SGCN). It then studies the strengths, weaknesses and applications of two promising wireless mesh routing protocols that could be used to implement the SGCN. Packet transmission reliability, latency and robustness of these two protocols are evaluated and compared by simulations in various practical SGCN scenarios. Finally, technical challenges and open research opportunities of the SGCN are addressed. Wireless Communications Networks for Smart Grid provides communication network architects and engineers with valuable proven suggestions to successfully implement the SGCN. Advanced-level students studying computer science or electrical engineering will also find the content helpful.

This SpringerBrief presents recent advances in the cognitive MAC designs for opportunistic spectrum access (OSA) networks. It covers the basic MAC functionalities and MAC enhancements of IEEE 802.11. Later chapters discuss the existing MAC protocols for OSA and classify them based on characteristic features.The authors provide new research in adaptive carrier sensing-based MAC designs tailored for OSA, which optimize spectrum utilization and ensure a peaceful coexistence of licensed and unlicensed systems. Analytically devised via optimization and game-theoretic approaches, these adaptive MAC designs are shown to effectively reduce collisions between both primary and secondary network users.Researchers and professionals working in wireless communications and networks will find this content valuable. This brief is also a useful study guide for advanced-level students in computer science and electrical engineering.

This SpringerBrief explores the advantage of relaying techniques in addressing the increasing demand for high data rates and reliable services over the air. It demonstrates how to design cost-effective relay systems that provide high spectral efficiency and fully exploit the diversity of the relay channel. The brief covers advances in achievable rates, power allocation schemes, and error performance for half-duplex (HD) and full-duplex (FD) amplify-and-forward (AF) single-relay systems. The authors discuss the capacity and respective optimal power allocation for a wide range of HD protocols over static and fading channels. Then, optimal amplification coefficients in terms of achievable rate are presented. Chapters also examine performance with finite constellations, including the error and diversity performance. The brief concludes with a capacity and error performance analysis of the FD relay mode of operation, where the residual self-interference due to FD transmission is explicitly taken into account. Amplify-and-Forward Relaying in Wireless Communications reveals the benefits and challenges of relaying techniques. It is designed for researchers and professionals in wireless communication. This material is also appropriate for advanced-level students in electrical engineering and computer science.

This SpringerBrief focuses on the coexistence concerns emerging in LTE networks using unlicensed frequency bands. It provides a comprehensive review on LTE networks and their unavoidable need for enhanced capacity to meet the demands for future applications, including a need for low-cost options.LTE using unlicensed frequency (U-LTE) is then introduced as the most promising solution, and discussed from various perspectives to unveil its benefits, challenges, and requirements for coexistence with the widely-deployed IEEE 802.11/Wi-Fi technology. Meeting these coexistence requirements is the most important factor for the acceptance of U-LTE, and the majority of this brief explores the big picture concerns and existing solutions related to coexistence-aware medium access protocols for background knowledge. A proposed network-aware adaptive listen-before-talk protocol is presented and evaluated.Finally, the authors identify a numberof open technical questions and potential research issues in U-LTE. This SpringerBrief is suitable for telecom engineers, researchers, and academic professionals with valuable knowledge and potential working or research directions when designing and developing medium access protocols for next generation wireless access networks.

There have been recent advancements in wireless network technologies such as wireless virtualization to accommodate the exponential growth in demand, as well as to increase energy and infrastructure efficiencies. This SpringerBrief discusses the user-association and resource-allocation aspects in Virtualized Wireless Networks (VWNs) and highlights key technology innovations to meet their requirements. Various issues in practical implementation of VWNs are discussed along with potential techniques such as Massive MIMO, Cloud-Radio Access Network (C-RAN), and non-orthogonal multiple access (NOMA).  This SpringerBrief will target researchers and professionals working on current and next-generation wireless networks. The content is also valuable for advanced-level students interested in wireless communications and signal processing for communications.

This book introduces the development of self-interference (SI)-cancellation techniques for full-duplex wireless communication systems. The authors rely on estimation theory and signal processing to develop SI-cancellation algorithms by generating an estimate of the received SI and subtracting it from the received signal.The authors also cover two new SI-cancellation methods using the new concept of active signal injection (ASI) for full-duplex MIMO-OFDM systems. The ASI approach adds an appropriate cancelling signal to each transmitted signal such that the combined signals from transmit antennas attenuate the SI at the receive antennas. The authors illustrate that the SI-pre-cancelling signal does not affect the data-bearing signal.This book is for researchers and professionals working in wireless communications and engineers willing to understand the challenges of deploying full-duplex and practical solutions to implement a full-duplex system. Advanced-level studentsin electrical engineering and computer science studying wireless communications will also find this book useful as a secondary textbook.

This SpringerBrief presents radio resource allocation schemes for buffer-aided communications systems over fading channels under statistical delay constraints in terms of upper-bounded average delay or delay-outage probability.This Brief starts by considering a source-destination communications link with data arriving at the source transmission buffer.  The first scenario, the joint optimal data admission control and power allocation problem for throughput maximization is considered, where the source is assumed to have a maximum power and an average delay constraints. The second scenario, optimal power allocation problems for energy harvesting (EH) communications systems under average delay or delay-outage constraints are explored, where the EH source harvests random amounts of energy from renewable energy sources, and stores the harvested energy in a battery during data transmission. Online resource allocation algorithms are developed when the statistical knowledge ofthe random channel fading, data arrivals, EH processes governing the system dynamics is unknown a-priori. This Brief continues with a source-relay-destination communications link with buffers available at both source and relay, as part of a multi-hop network. Optimal resource allocation schemes for this 3-node relaying system to maximize its effective capacity under a delay-outage constraint are proposed, with special emphasis on relay roles: Half-duplex (HD) or full-duplex (FD) relay operation. With HD relay, the adaptive link selection relaying problem jointly with both fixed and adaptive power allocation schemes is investigated. Within each transmission frame, either the source-relay link or the relay-destination link is selected to be active depending on the channel conditions. With FD relay under the presence of non-zero residual self-interference (SI).This Brief also presents source and relay power allocation schemes for both cases of available knowledge of thechannel state information at transmitter (CSIT): instantaneous or statistical. Professional and researchers working in this related field and advanced-level students in electrical or computer engineering will find the content valuable as a reference.