This book presents a vision for the coming years, one that the editors of this book, active employees of Research In Motion (RIM) and AT&T Labs, and the collective chapter authors see ahead in terms of emerging fourth generation (4G) wireless technology trends and best practices. Each section explores the resulting challenges and technical opportunities that will arise in creating and delivering 4G networks for the emerging applications and services. The book also examines the fundamentals of advanced physical layer and radio resource management as the basis for cross layer and cross network optimization that will emerge for increased mobility and services in video, cloud computing virtualization, entertainment, education, health, and security.
The book editors have known each other for many years and they have worked together in various standards and university communities. They have organized this book especially for researchers, students, network engineers and designers and leaders of emerging companies, decision makers in standards, consumers, and product developers. Our goal is to provoke a discussion about the impact of orthogonal frequency division multiplexing (OFDM) technology trends in the coming years. This is essential in understanding a change, anticipating a change, even controlling a change, and ultimately making it work globally.
The fourth generation (4G) of cellular wireless is a successor to 3G and 2G standards. It is understood that 4G systems may upgrade existing communication networks and are expected to provide a comprehensive and secure IP based solutions where facilitate existing and emerging services such as voice, data, streamed multimedia, sensory, e-health, and social networking. It is expected that 4G will be provided to users on an "Anytime, Anywhere" basis and at much higher data rates compared to the previous generations. Moreover, the explosion of new applications over the mobile broadband networks (e.g., plethora of new BlackBerry and iPhone applications) has made it critical to have an efficient 4G network deployment to ensure widespread success of the emerging mobile broadband applications.
The springboard that we have organized for each section is a closer look at the dominant factors influencing the network topologies, their applications, and network practices in the next 2-5 years. These practices will transform the wireless evolution towards 4G world where seamless access to information will be the basic requirements in the emerging world.
The first part of this book is devoted to discuss future network architectures, deployments, and new technologies. This part deals with adoption issues and challenges of 4G systems. There are several advanced architectures that support efficient radio resource and mobility management for all-IP networking which is the ultimate goal of 4G wireless networks. These new designs provide possibilities for developing a next generation hybrid wireless network, which is discussed in detail in this part. This includes cross layer designs to provide quality of service, end-to-end delay reductions, seamless mobility, and IP-based transport provisioning. Several new technologies including cooperative services, services from high altitude platforms and radio over fiber are also considered as enabling techniques in hybrid networks. Moreover, some new business design models for 4G networks are introduced here, which they evaluate the market readiness for 4G and what requires supporting a next generation.
The second part of the book is devoted to radio access protocols, including; scheduling, quality of service, mobility, hand over issues, and cross layer designs. After a thorough review of radio access protocols, advanced multi-level scheduling techniques are introduced to control both radio access and the core network. An end-to-end quality of service control is considered for all-IP systems. Basic services such as VoIP, e-mail and web browsing are analyzed. Several challenges for streaming services are quantified, e.g. variations in inter-packet arrival time, or jitter, and the periodic loss and/or re-ordering of data. This part includes cross layer frameworks which incorporate several parameters distributed across network layers to optimize quality of service, mobility, and handover for different traffic types.
The third part of this book is devoted to advances in physical layer for 4G systems. Characteristics of OFDM along with a comparison between OFDM, code division multiple access (CDMA) and time division multiple access (TDMA) methods are the basis for this part. Several advanced multiple-access transmission schemes are introduced here, such as Block Spread OFDM or orthogonal frequency code division (OFCD). The OFCD is the combination of OFDM and CDMA which yields a significant improvement in 4G systems with the compensation of more sophisticated designs for transmitters and receivers. It is emphasized however that OFDM is the heart of wireless communication systems and CDMA can play a major role in 4G systems. The next generation of CDMA technology for 4G systems is also introduced based on a new complementary code design. Enhanced decoding techniques play a major role in the superior performance of an advanced physical layer. Reconfigurable and scalable turbo decoder architectures are presented here, which can be used in several standards with a common hardware module. In addition, new multiple antenna decoding techniques are introduced to enhance the joint iterative decoding in turbo decoding for 4G systems. Moreover, several new techniques are explored to enhance the radio system capacity such as interference measurement and cooperative communications by incorporating relays as part of physical layer enhances.
All these parts will lead to the emergence of what 4G will bring for us as the basis for a Virtual Society; a society in which everybody and everything will be virtually connected and linked to 4G mobile IP networks. Moreover, almost everyone and everything will be accessible from everywhere via the Internet using all sorts of devices.