Intelligent Reflecting Surface

Intelligent reflecting surfaces (IRSs) are programmable arrays of metamaterials that dynamically reshape wireless signals, aiming to improve spectral and energy efficiency in communication systems. Current research heavily focuses on optimizing IRS deployment and control, often employing deep reinforcement learning (various architectures like DDPG, TD3, and Q-learning variants) and other machine learning techniques (e.g., extreme learning machines) for tasks such as channel estimation, resource allocation, and user association, particularly in conjunction with unmanned aerial vehicles (UAVs). This technology holds significant promise for enhancing the performance of next-generation wireless networks, especially in challenging environments and applications like mobile edge computing and the Internet of Things.