Integration of a GNN and U-Net for Hybrid Beamforming in mm-Wave m-MIMO Systems
摘要
Massive Multiple-Input Multiple-Output (m-MIMO) systems with Millimeter-Wave (mm-Wave) promise high data rates and high spectral efficiency (SE) in beyond fifth-generation (B5G) wireless networks. This paper proposes a novel deep learning approach that synergizes Graph Neural Networks (GNNs) and U-Net architectures to efficiently learn optimal hybrid beamforming strategies from channel state information (CSI). The GNN is used to capture the spatial and topological relationships between antennas and users for generalizing the system in various configurations and distributions. Simultaneously, the U-Net is used to process the structured CSI representations for extracting spatial features for enhanced precoder rebuilding. The proposed approach is trained using a loss function for optimizing SE and Bit Error Rate (BER). Simulation results show that the integrated GNN and U-Net approach achieves superior performance to conventional methods, with significantly reduced computational overhead during inference. Across SNR values from − 18 dB to 6 dB, the method yields 9% to 54% SE improvement over state-of-the-art hybrid beamforming techniques while maintaining lower BER.