A Low‐Pilot‐Overhead Two‐Stage Channel Estimation Scheme for XL‐RIS‐Assisted Multi‐User Terahertz Systems
Accurate channel state information (CSI) is essential for exploiting terahertz communication and reconfigurable intelligent surfaces (RISs) in sixth‐generation (6G) wireless systems. However, CSI acquisition in RIS‐assisted terahertz systems requires prohibitive pilot overhead because the cascaded channel has high sp...