Algorithm for Determination of Cutoff Frequency of Noise Floor Level for Terahertz Time-Domain Signals

Abstract

The frequency-dependent signal-to-noise ratio of terahertz time-domain signals is a relevant source of uncertainty for parameters measured with it. It also limits the total usable bandwidth of such signals. In the great majority of cases, the processes to establish the limits of this usable bandwidth are determined based on the experience of the user. Therefore, it is desirable to develop a procedure to automate this calculation. In this work, a method to estimate the bandwidth of terahertz time-domain signals is presented. Different spectra were analyzed, showing the potential of the algorithm in the calculation of cutoff frequencies which delimits the usable bandwidth.