通过改变采样点数,理论优化了Hadamard变换离子迁移谱(Hadamard transform ion mobility spectrometry, HT-IMS)谱图的采样速率;通过增加模拟的白噪声,分析了 该方法提高谱图信噪比的效果和对分辨率的影响。 初步结果表明,在单次离子门门宽0.4 ms内,采集8个及以上数据点可以完整地反演IMS谱图; Hadamard变换方法得 到的谱图的信噪比是传统IMS谱图信噪比的15.8倍,是相同时间内多次传统IMS谱图平均后信噪比的4.6倍; 变换过程对IMS谱图分辨率无明显影响。Hadamard变换IMS的模拟不仅为采样速率等参数的选择和优化提供理论依据, 而且为下一步实验控制和反演奠定软件基础。

Theoretically, the sampling rate of Hadamard transform ion mobility spectrometry (HT-IMS) spectra was optimized by changing the sampling data points. By adding white noise of simulation, the effect of improving signal-to-noise ratio (SNR) of spectra of the proposed approach and its influence on the resolution were analyzed. Preliminary results show that it can retrieve the IMS spectra by sampling at least 8 data points within a single ion gate width of 0.4 ms. The SNR of the spectra using Hadamard transform approach is 15.8 times as large as that of conventional IMS spectra, as well is 4.6 times as large as that of the spectra acquired by averaging multiple conventional spectra with the same sampling time. The transformational process has no obvious influence on the resolution of the IMS spectra. The simulation of HT-IMS not only provides theoretical evidences to choose and optimize sampling rate and so on, but also establishs the software foundation for next experimental control and transformation.