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arXiv · 2511.15221

Theoretical and Empirical Study of Spatial Power Focusing Effect for Sparse Arrays at Terahertz Band

Yongchao He·Taihao Zhang·Cunhua Pan·Hong Ren·Xianzhe Chen·Tian Qiu·Bingchang Hua·Jiangzhou Wang
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Abstract

This work investigates the spatial power focusing effect for large-scale sparse arrays at terahertz (THz) band, combining theoretical analysis with experimental validation. Specifically, based on a Green's function channel model, we analyze the power distribution along the $z$-axis, deriving a closed-form expression to characterize the focusing effect. Furthermore, the factors influencing the focusing effect, including phase noise and positional deviations, are theoretically analyzed and numerically simulated. Finally, a 300 GHz measurement platform based on a vector network analyzer (VNA) is constructed for experimental validation. The measurement results demonstrate close consistence with theoretical simulation results, confirming the spatial power focusing effect for sparse arrays.

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Yongchao He, Taihao Zhang, Cunhua Pan, Hong Ren, Xianzhe Chen, Tian Qiu, Bingchang Hua, Jiangzhou Wang. 2025-11-19. Theoretical and Empirical Study of Spatial Power Focusing Effect for Sparse Arrays at Terahertz Band. https://arxiv.org/abs/2511.15221

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