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arXiv · 1712.06669

Corrective Re-gridding Techniques for Non-Uniform Sampling in Time Domain Terahertz Spectroscopy

A. M. Potts·T. T. Mai·M. T. Warren·R. Valdés Aguilar
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Abstract

Time domain terahertz spectroscopy typically uses mechanical delay stages that inherently suffer from non-uniform sampling positions. We review, simulate, and experimentally test the ability of corrective cubic spline and Shannon re-gridding algorithms to mitigate the inherent sampling position noise. We present simulations and experimental results that show re-gridding algorithms can increase the signal to noise ratio within the frequency range of 100 GHz to 2 THz. We also predict that re-gridding corrections will become increasingly important to both spectroscopy and imaging as THz technology continues to improve and higher frequencies become experimentally accessible.

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A. M. Potts, T. T. Mai, M. T. Warren, R. Valdés Aguilar. 2017-12-18. Corrective Re-gridding Techniques for Non-Uniform Sampling in Time Domain Terahertz Spectroscopy. https://doi.org/10.1364/josab.36.001037

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