Improvement of submillimeter spectrometric measurement via deconvolution

Abstract

Spectrometry at submillimeter wavelengths (terahertz frequency range) is a promising field of applications but one which presents significant difficulties. The sources at these domains have generally low power, the measurements are noisy and the resolution of the measured spectra is limited by diffraction. We propose a method to improve the spectral resolution in Hadamard spectroscopy for the submillimeter spectral region. The method involves oversampling the spectrum using multiple shifted acquisitions and deconvolution. In order to find the most appropriate deconvolution method, several known algorithms are evaluated. They are: the Lucy-Richardson algorithm, the Maximum Entropy Method (MEM) and the Wiener filter. MEM proved to be the best one. It outperforms the other tested methods by a percentage over 16%.