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arXiv · 2408.04505

Feedback Design with VQ-VAE for Robust Precoding in Multi-User FDD Systems

Nurettin Turan·Michael Baur·Jianqing Li·Wolfgang Utschick
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Abstract

In this letter, we propose a vector quantized-variational autoencoder (VQ-VAE)-based feedback scheme for robust precoder design in multi-user frequency division duplex (FDD) systems. We demonstrate how the VQ-VAE can be tailored to specific propagation environments, focusing on systems with low pilot overhead, which is crucial in massive multiple-input multiple-output (MIMO). Extensive simulations with real-world measurement data show that our proposed feedback scheme outperforms state-of-the-art autoencoder (AE)-based compression schemes and conventional Discrete Fourier transform (DFT) codebook-based schemes. These improvements enable the deployment of systems with fewer feedback bits or pilots.

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Nurettin Turan, Michael Baur, Jianqing Li, Wolfgang Utschick. 2024-08-08. Feedback Design with VQ-VAE for Robust Precoding in Multi-User FDD Systems. https://arxiv.org/abs/2408.04505

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