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arXiv · 2603.03851

Pearcey-Inspired Quartic Wavefront Shaping for Obstructed Near-Field Multi-User Communications

Yifeng Qin·Jing Chen·Zhi Hao Jiang
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Abstract

Radiative near-field (RNF) beamforming is vulnerable to blockages that disrupt Fresnel zones. This letter proposes an obstruction-unaware wavefront shaping strategy inspired by catastrophe optics. By superimposing a calibrated quartic phase, we generate a Pearcey-like wave packet that exhibits structural stability against perturbations. We establish a fair comparison protocol where the quartic beam is calibrated in free space to avoid exploiting obstruction knowledge. Numerical results demonstrate up to 8.5~dB SINR gain over conventional focusing for multi-user scenarios near the depth-of-focus limit. Crucially, this gain stems from improved channel conditioning under partial blockage, which mitigates the severe noise amplification inherent to zero-forcing precoding.

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Yifeng Qin, Jing Chen, Zhi Hao Jiang. 2026-03-04. Pearcey-Inspired Quartic Wavefront Shaping for Obstructed Near-Field Multi-User Communications. https://arxiv.org/abs/2603.03851

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