Exploring the Potential of Large Language Models for Massive MIMO CSI Feedback
Yiming Cui, Jiajia Guo, Chao-Kai Wen, Shi Jin, En Tong
TL;DR
This work addresses the overhead of downlink CSI feedback in massive MIMO by introducing a pre-trained large language model (LLM) framework for CSI reconstruction. It combines a four-module pipeline—pre-processing, embedding, a pre-trained GPT-2, and post-processing—tuned with minimal parameter updates to leverage language priors while bridging CSI data to textual representations. Empirical results show the LLM-based approach outperforms small DL baselines and TransNet in NMSE and GCS, with stronger gains at higher compression ratios and robust generalization with limited training data. The findings demonstrate a cost-efficient, scalable pathway to intelligent CSI feedback that exploits knowledge learned from natural language processing to enhance wireless system performance.
Abstract
Large language models (LLMs) have achieved remarkable success across a wide range of tasks, particularly in natural language processing and computer vision. This success naturally raises an intriguing yet unexplored question: Can LLMs be harnessed to tackle channel state information (CSI) compression and feedback in massive multiple-input multiple-output (MIMO) systems? Efficient CSI feedback is a critical challenge in next-generation wireless communication. In this paper, we pioneer the use of LLMs for CSI compression, introducing a novel framework that leverages the powerful denoising capabilities of LLMs -- capable of error correction in language tasks -- to enhance CSI reconstruction performance. To effectively adapt LLMs to CSI data, we design customized pre-processing, embedding, and post-processing modules tailored to the unique characteristics of wireless signals. Extensive numerical results demonstrate the promising potential of LLMs in CSI feedback, opening up possibilities for this research direction.
