Many baseline correction approaches have been developed to address baseline artifacts observed in measured infrared (IR) absorption spectra during post-processing. These approaches offer distinct advantages and disadvantages, and the choice of which one to employ depends on the complexity of baseline artifacts present in a particular application. In this paper, we compare the performance of two baseline correction approaches: a frequency-domain polynomial fitting approach and a time-domain modified free induction decay approach, under various baseline scenarios, spectral resolutions, and noise levels for mixtures containing up to 464 species. Our results showed that the frequency-domain approach outperformed the time-domain approach by a factor of up to 16 when the baseline was represented by a sine wave with fewer than two cycles over the full spectral range. On the other hand, the time-domain approach performed up to 12 times better when the baseline featured two cycles of a sine wave. Additionally, we observed that the time-domain approach exhibited higher sensitivity to spectral resolution and underperformed when the noise level was high. The findings of this study emphasize the importance of numerically testing a few candidate approaches for a given application, taking into consideration baseline characteristics, as well as the spectral resolution and noise constraints of the application.

中文翻译：

---

含有多达 464 种成分的混合物的红外吸收光谱频域和时域基线校正方法的比较

人们已经开发了许多基线校正方法来解决在后处理期间测量的红外 (IR) 吸收光谱中观察到的基线伪影。这些方法具有明显的优点和缺点，选择使用哪一种方法取决于特定应用中存在的基线工件的复杂性。在本文中，我们比较了两种基线校正方法的性能：频域多项式拟合方法和时域改进的自由感应衰减方法，在各种基线场景、光谱分辨率和包含多达 464 种物质的混合物的噪声水平下的性能。我们的结果表明，当基线由整个光谱范围内周期少于两个的正弦波表示时，频域方法的性能比时域方法高出 16 倍。另一方面，当基线具有两个正弦波周期时，时域方法的性能提高了 12 倍。此外，我们观察到时域方法对光谱分辨率表现出更高的敏感性，并且在噪声水平较高时表现不佳。这项研究的结果强调了对给定应用的一些候选方法进行数值测试的重要性，同时考虑基线特征以及应用的光谱分辨率和噪声限制。