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arXiv · 2508.04169

Subspace Fitting Approach for Wideband Near-Field Localization

Ruiyun Zhang·Zhaolin Wang·Zhiqing Wei·Yuanwei Liu·Zehui Xiong·Zhiyong Feng
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Abstract

Two subspace fitting approaches are proposed for wideband near-field localization. Unlike in conventional far-field systems, where distance and angle can be estimated separately, spherical wave propagation in near-field systems couples these parameters. We therefore derive a frequency-domain near-field signal model for multi-target wideband systems and develop a subspace fitting-based MUSIC method that jointly estimates distance and angle. To reduce complexity, a Fresnel approximation MUSIC algorithm is further introduced to decouple the distance and angle parameters. Numerical results verify the effectiveness of both proposed approaches.

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Ruiyun Zhang, Zhaolin Wang, Zhiqing Wei, Yuanwei Liu, Zehui Xiong, Zhiyong Feng. 2025-08-06. Subspace Fitting Approach for Wideband Near-Field Localization. https://arxiv.org/abs/2508.04169

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