Method and arrangement for the drift correction a discrete-time measurement signals based on a reference signal, in particular in the absorption-spectroscopy trace-gas analysis

摘要

The invention relates to a method and an arrangement for drift correction of temporally discrete measurement signals relative to a reference signal, in particular for application in absorption-spectroscopic trace-gas analysis. By means of the invention, it is intended to increase the accuracy of the measurement signals obtained over a multiplicity of spectra or scans. For this purpose, an on-line drift correction is provided, which can be used, in particular, in spectroscopy using semiconductor diode lasers, but also in all other measurement methods in which signal drifts may lead to deterioration of the measurement result. Since an on-line analysis and correction of the relative shift between measurement and calibration spectrum or the reference signal are first carried out before the respective data are compiled by averaging, the otherwise required storage of a large number of raw spectra for subsequent off-line analysis is obviated. The on-line drift correction method according to the invention can be implemented both purely using hardware or purely using software and in a combination of hardware and software. IMAGE