Название: Reconfigurable Intelligent Surface-Empowered 6G
Автор: Hongliang Zhang, Boya Di, Lingyang Song
Издательство: Springer
Год: 2021
Страниц: 260
Язык: английский
Формат: pdf (true), epub
Размер: 40.2 MB

This book presents novel RIS-Based Smart Radio techniques, targeting at achieving high-quality channel links in cellular communications via design and optimization of the RIS construction. Unlike traditional antenna arrays, three unique characteristics of the RIS will be revealed in this book. First, the built-in programmable configuration of the RIS enables analog beamforming inherently without extra hardware or signal processing. Second, the incident signals can be controlled to partly reflect and partly transmit through the RIS simultaneously, adding more flexibility to signal transmission. Third, the RIS has no digital processing capability to actively send signals nor any radio frequency (RF) components. As such, it is necessary to develop novel channel estimation and communication protocols, design joint digital and RIS-based analog beamforming schemes and perform interference control via mixed reflection and transmission. This book also investigates how to integrate the RIS to legacy communication systems.

Launching from fifth-generation communications, which provide a single platform enabling a variety of data services, evolution towards sixth-generation (6G) has been kicked off, envisioning future wireless networks to become distributed intelligent communications, sensing, and localization systems. Though such a demand has gained support from existing techniques such as massive MIMO and small cells, they heavily depend on the quality of the uncontrollable wireless environments. Differently, reconfigurable intelligent surface (RIS) as a new type of ultra-thin meta material inlaid with multiple sub-wavelength scatters can create favorable propagation conditions by controlling the phase shifts of the reflected waves at the surface such that the received signals are directly reflected towards the receivers without any extra cost of power sources or hardware. It provides a revolutionarily new approach to actively improve the link quality and coverage, which sheds light into the future 6G. Due to the coupling between radio propagation and discrete phase shifts of RIS, existing protocols and design methodologies cannot be directly applied any more. Therefore, it is essential to develop new communication and signal processing techniques and to explore various RIS-based applications such as intelligent sensing and localization.

This book targets researchers and graduate-level students focusing on communications and networks. Signal processing engineers, computer and information scientists, applied mathematicians and statisticians, who work in RIS research and development will also find this book useful.