New Directions in Wireless Communications Systems: From Mobile to 5G.
We are experiencing the dawn of what is called the digital age. The Internet and digital technologies are transforming our world. Wireless communication systems constitute a basic component of the current and the future information society. The fifth generation of communication systems, or 5G, will be, in the years to come, the most critical building block of what is referred to as a digital society. It is expected that 5G will be a truly converged network environment, because not only mobile communications systems but also other wireless systems and wired networks will coexist and use the same infrastructure.
The vision ahead is that 5G will provide virtually ubiquitous, ultra-fastbroadband, connectivity not only to millions of individual users but also to billions of connected objects. Therefore, 5G systems should have the capabilities to (a) serve the datahungry devices, for example, smartphones and tablets, providing rates of Gbps; (b) enable machine-to-machine (M2M) communications, for example, vehicle-tovehicle (V2V) networks; (c) allow for interconnectivity of massive devices, for example, sensors and e-health equipment; and (d) support a wide range of applications and sectors. All these expectations set a wide variety of technical requirements for the design of 5G systems, including higher peak and user data rates, extremely low latency and response times, enhanced indoor and outdoor coverage, significantly increased number of devices, reaching the astronomical number of 100 billion, seamless mobility, security and privacy, increased battery lifetime, and improved quality of service (QoS) while maintaining low operational costs.
All the predictions available in the literature lead to the conclusion that beyond 2020, wireless communication systems will be able to support more than 1000 times the traffic volume served today by the current telecommunication systems. This extremely high traffic load is one of the major issues faced by the 5G designers, manufacturers, and researchers, alike. It appears that this challenge will be addressed by a combination of parallel techniques that will use more spectrum more flexibly, realize higher spectral efficiency, and densify cells. Therefore, novel techniques and paradigms should be developed to support such challenges. In this context, this book addresses diverse key-point issues of the nextgeneration wireless communication systems and attempts to identify promising solutions. The core of the book deals with the techniques and methods belonging to what is generally referred to as radio access network. The increased needs and the users’ expectations from the next-generation systems have been based for long on enabling technologies provided by the physical layer. These technologies are mainly developed to combat signal degradations imposed by the wireless channel and to support increased user data rates and improved QoS.
The book addresses diverse key-point issues of next-generation wireless communications systems and identifies promising solutions. The book’s core is concentrated to techniques and methods belonging to what is generally called radio access network.