A novel WMS algorithm and an example of methane measurement

Calibration-free wavelength modulation spectroscopy based on the height-width parameters of the 2nd harmonic

A calibration-free wavelength modulation spectral method based on the height-width characteristics of 2ndharmonic is proposed. Compared with the traditional harmonic waveform fitting method, this method only needs one filtering process and has lower requirements for computing resources. In addition, the proposed method is theoretically more suitable for measurements at complex gas compositions since it does not require the use of excessive spectral parameters from the HITRAN database.