差分吸收光谱法测量大气污染的测量误差分析

Error Analysis in Differential Optical Absorption Spectroscopy

差分吸收光谱技术被广泛地应用于测量大气中微量元素的浓度 ,尽管该技术利用最小二乘法来反演待测气体的浓度 ,能够得到很高的测量精度。但是 ,由于仪器本身的噪声以及测量波段其它气体的干扰等 ,使得仪器的测量有一定的误差 ,而且上述因素还决定着仪器的测量下限。对差分吸收光谱方法的测量误差以及引起误差的原因作了详细的分析。

The differential optical absorption spectroscopy (DOAS) has become a widely used method to measure the concentration of trace gases in the atmosphere. By using the least squares fits of reference spectra to the measurement spectra, it usually has a high measurement precision. But in order to determine the detection limit, the error must be considered seriously. The measurement error in DOAS is analyzed, it is caused mainly by noise, selection of waveband and interferences of other trace gases. The relationship between error and those factors is discussed.