Title: Corrective Re-gridding Techniques for Non-Uniform Sampling in Time Domain Terahertz Spectroscopy,
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.