🤖 AI Summary
Traditional channel knowledge maps (CKMs) in MIMO systems suffer from insufficient accuracy for beamforming and precoder selection, coupled with high modeling complexity. To address this, we propose a codebook-aware CKM construction method. Our approach explicitly incorporates DFT-based precoding vectors into the CKM generation framework and introduces TransUNet—a hybrid architecture that synergistically combines UNet’s multi-scale local feature extraction with Transformer’s global linear modeling capability—enabling electromagnetic-environment-driven end-to-end CKM regression. Experimental results demonstrate a 17% reduction in root-mean-square error (RMSE) over the state-of-the-art RadioWNet. The method supports real-time CKM generation and is publicly available as open-source code.
📝 Abstract
Channel knowledge map (CKM) has emerged as a crucial technology for next-generation communication, enabling the construction of high-fidelity mappings between spatial environments and channel parameters via electromagnetic information analysis. Traditional CKM construction methods like ray tracing are computationally intensive. Recent studies utilizing neural networks (NNs) have achieved efficient CKM generation with reduced computational complexity and real-time processing capabilities. Nevertheless, existing research predominantly focuses on single-antenna systems, failing to address the beamforming requirements inherent to MIMO configurations. Given that appropriate precoding vector selection in MIMO systems can substantially enhance user communication rates, this paper presents a TransUNet-based framework for constructing CKM, which effectively incorporates discrete Fourier transform (DFT) precoding vectors. The proposed architecture combines a UNet backbone for multiscale feature extraction with a Transformer module to capture global dependencies among encoded linear vectors. Experimental results demonstrate that the proposed method outperforms state-of-the-art (SOTA) deep learning (DL) approaches, yielding a 17% improvement in RMSE compared to RadioWNet. The code is publicly accessible at https://github.com/github-whh/TransUNet.