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arXiv · 2304.06141

Performance Analysis for Near-Field MIMO: Discrete and Continuous Aperture Antennas

Ziyi Xie·Yuanwei Liu·Jiaqi Xu·Xuanli Wu·Arumugam Nallanathan
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Abstract

Performance analysis is carried out in a near-field multiple-input multiple-output (MIMO) system for both discrete and continuous aperture antennas. The effective degrees of freedom (EDoF) is first derived. It is shown that near-field MIMO systems have a higher EDoF than free-space far-field ones. Additionally, the near-field EDoF further depends on the communication distance. Based on the derived EDoF, closed-form expressions of channel capacity with a fixed distance are obtained. As a further advance, with randomly deployed receivers, ergodic capacity is derived. Simulation results reveal that near-field MIMO has an enhanced multiplexing gain even under line-of-sight transmissions. In addition, the performance of discrete MIMO converges to that of continuous aperture MIMO.

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Ziyi Xie, Yuanwei Liu, Jiaqi Xu, Xuanli Wu, Arumugam Nallanathan. 2023-04-12. Performance Analysis for Near-Field MIMO: Discrete and Continuous Aperture Antennas. https://arxiv.org/abs/2304.06141

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