Efficient Data Transmission With Compressed Channel Estimation in RIS-Assisted mmWave MIMO Systems

To improve wireless connectivity, reconfigurable intelligent surface (RIS) offers an energy-efficient solution in millimeter wave (mmWave) multi-input multi-output (MIMO) systems. However, the achievable spectrum efficiency (SE) has been limited by challenges associated with channel estimation (CE) and hybrid beamforming design. To address these issues, we propose an efficient data transmission (DT) scheme with two-stage compressed sensing (CS)-based CE by exploiting the sparse angular domain channel structure and pruning insignificant components. Simulation results demonstrate that the proposed method achieves reduction in pilot overhead and complexity of CE, and higher SE of DT via iterative optimization.