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arXiv · 2312.04602

Low-Complexity Channel Estimation for Extremely Large-Scale MIMO in Near Field

Chun Huang·Jindan Xu·Wei Xu·Xiaohu You·Chau Yuen·Yijian Chen
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Abstract

The extremely large-scale massive multiple-input multiple-output (XL-MIMO) has the potential to achieve boosted spectral efficiency and refined spatial resolution for future wireless networks. However, channel estimation for XL-MIMO is challenging since the large number of antennas results in high computational complexity with the near-field effect. In this letter, we propose a low-complexity sequential angle-distance channel estimation (SADCE) method for near-field XL-MIMO systems equipped with uniformly planar arrays (UPA). Specifically, we first successfully decouple the angle and distance parameters, which allows us to devise a two-dimensional discrete Fourier transform (2D-DFT) method for angle parameters estimation. Then, a low-complexity distance estimation method is proposed with a closed-form solution. Compared with existing methods, the proposed method achieves significant performance gain with noticeably reduced computational complexity.Numerical results verify the superiority of the proposed near-field channel estimation algorithm.

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Chun Huang, Jindan Xu, Wei Xu, Xiaohu You, Chau Yuen, Yijian Chen. 2023-12-07. Low-Complexity Channel Estimation for Extremely Large-Scale MIMO in Near Field. https://arxiv.org/abs/2312.04602

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