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arXiv · 2505.02611

Multi-dimensional Parameter Estimation in RIS-aided MU-MIMO-OFDM Channels

Linlin Mo·Yi Song·Fabio Saggese·Xinhua Lu·Zhongyong Wang·Petar Popovski
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Abstract

We address the channel estimation (CE) problem in reconfigurable intelligent surface (RIS) aided orthogonal frequency-division multiplexing (OFDM) systems by proposing a dual-structure and multi-dimensional transformations (DS-MDT) algorithm.The proposed approach leverages the dual-structure features of the channel parameters to assist users experiencing weaker channel conditions, thereby enhancing CE performance. Moreover, given that the channel parameters are distributed across multiple dimensions of the received tensor, the proposed algorithm employs multi-dimensional transformations to isolate and extract distinct parameters. The numerical results demonstrate the proposed algorithm reduces the normalized mean square error (NMSE) by up to 10 dB while maintaining lower complexity compared to state-of-the-art methods.

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Linlin Mo, Yi Song, Fabio Saggese, Xinhua Lu, Zhongyong Wang, Petar Popovski. 2025-05-05. Multi-dimensional Parameter Estimation in RIS-aided MU-MIMO-OFDM Channels. https://arxiv.org/abs/2505.02611

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