Channel Estimation for RIS-Empowered Wideband Wireless Systems

This chapter focuses on channel estimation for wideband wireless systems empowered by Reconfigurable Intelligent Surfaces (RISs). First, channel estimation schemes for RIS-aided orthogonal frequency division multiplexing (OFDM) communication systems are discussed, including an ON/OFF-based and a progressive method. A performance comparison is provided, supported by simulation results. Subsequently, channel estimation for RIS-aided cyclic-prefixed single-carrier (CPSC) communication systems are discussed, addressing both an one-step and a progressive method. A comparative analysis of those two single-carrier channel estimation methods is presented.