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arXiv · 2610.34224

Fading Suppression in Distributed Acoustic Sensing Using Frequency-Domain Replica Reconstruction and Noise-Whitened Principal Component Combining

Ziang Chen·Zhiyang Xue·Huan Huang·Yuhan Jiang·Dongdong Zou·Gangxiang Shen·Yi Cai
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Abstract

Frequency-selective Rayleigh fading in distributed acoustic sensing (DAS) based on phase-sensitive optical time-domain reflectometry (phi-OTDR) calls for effective diversity, but existing rotated-vector-sum (RVS) combining of nonoverlapping subbands incurs a spatial-resolution penalty. In this letter, we propose frequency-domain replica reconstruction and noise-whitened principal component combining (PCC) that combines a full-band replica and overlapping subbands using fixed weights estimated across probing periods after whitening correlated replica noise. This approach retains wider subbands and reduces reliance on noisy first-period alignment, balancing diversity with nominal spatial resolution. Experiments over approximately 7.1 km of fiber with 16-microsecond linear frequency-modulated (LFM) pulses recover 500-Hz vibrations with reduced background phase excursions and a 2.46-2.76-dB improvement in the vibration-to-background ratio (VBR) over the first-period RVS.

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Ziang Chen, Zhiyang Xue, Huan Huang, Yuhan Jiang, Dongdong Zou, Gangxiang Shen, Yi Cai. 2026-10-25. Fading Suppression in Distributed Acoustic Sensing Using Frequency-Domain Replica Reconstruction and Noise-Whitened Principal Component Combining. https://arxiv.org/abs/2610.34224

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