ABSTRACT
This chapter presents an overview of intelligent reflecting surface (IRS)-empowered wireless communication systems. Conventional network optimization in wireless communication systems has been limited to transmission control at transceivers, with little attention has been paid to the wireless propagation environment. The chapter explores the integration of IRS with various advanced transmission technologies, such as millimeter wave/terahertz, non-orthogonal multiple access, mobile edge computing, and physical layer security. It discusses the effects of hardware impairments and imperfect channel state information on the IRS system performance. The chapter highlights several open issues to be addressed. Next-generation wireless communication systems will operate at higher frequencies to support applications that require sensing of the surrounding environment and accurate localization. Sensing and localization models in the near-field that exploit the information in the wavefront curvature needs to be developed. Accordingly, machine learning-empowered IRS systems are of practical interest.
