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arXiv · 2606.03999

Airy Beam Dispersion in Near-Field Wideband Terahertz Communications

Yongchao Qu·Wanming Hao·Gangcan Sun
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Abstract

This letter investigates Airy beam dispersion in near-field wideband terahertz communications. Unlike conventional focusing beams, whose dispersion mainly appears as focal-point migration, Airy beams exhibit frequency-dependent shifts of both the reference focusing point and the self-bending main-lobe trajectory. Based on the Fresnel diffraction integral, a closed-form trajectory expression is derived to characterize the dispersion behavior across subcarriers. Furthermore, a true-time-delay (TTD)-assisted Airy beamforming structure is developed to actively control the trajectory dispersion. By properly designing the time delay parameters, the proposed scheme can either generate frequency-dependent curved trajectory clusters for sensing-oriented scanning or suppress trajectory drift for reliable communication.

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Yongchao Qu, Wanming Hao, Gangcan Sun. 2026-05-23. Airy Beam Dispersion in Near-Field Wideband Terahertz Communications. https://arxiv.org/abs/2606.03999

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