分析化学2018，Vol.46Issue(5)：723-728,6.DOI:10.11895/j.issn.0253-3820.171253
傅里叶变换微波光谱仪的信号采集与数据处理研究
Investigation on Signal Acquisition and Data Processing of A Fourier Transform Microwave Spectrometer
摘要
Abstract
As one of the most important laboratory tools for the research of quantum chemistry and astrochemistry, a microwave spectrometer can make accurate measurement of molecular spectra arising from rotational transitions. Fourier transform microwave (FTMW) spectrometers, in many cases, require down-conversion mixing plans by using mixers to bring the molecular signal down for A/D sampling, and multiple signal averaging to improve the signal/noise ratio as well. Two detection schemes, homodyne and heterodyne detection modes,were proposed in this project along with two data processing plans, averaging in the time domain and averaging in the frequency domain,to develop efficient,sensitive and accurate detection solutions for molecular rotational spectroscopy. With 0. 5% OCS gas in argon as standard sample, verification experiment was conducted with frequency difference between LO and cavity resonance at 200 MHz and 0.4 MHz. The experimental results indicate that, the heterodyne detection method can provide better sensitivity than the homodyne scheme, but with increased cost for more devices, while the time-domain averaging can obtain much better signal-to-noise ratio than frequency-domain averaging,but with stronger data processing capacity and more time required.关键词
微波光谱仪/分子转动光谱/傅里叶变换/零差式检测/外差式检测Key words
Microwave spectrometer/Rotational spectroscopy/Fourier transform/Homodyne detection/Heterodyne detection引用本文复制引用
唐辉,朱海奇,周卓辉,许孜,孙铭,李力,张玉珍,陈钱,康路..傅里叶变换微波光谱仪的信号采集与数据处理研究[J].分析化学,2018,46(5):723-728,6.基金项目
本文系国家自然科学基金项目(Nos.U1531107,61627802)、中央高校基本科研业务费专项资金(Nos.30915011316,30916011103)、江苏省"高层次创新创业人才引进计划"项目、南京理工大学本科生科研训练'百千万'计划项目(No.201610288030x)和江苏省光谱成像与智能感知重点实验室2018年开放基金资助 This work was supported by the National Natural Science Foundation of China(Nos.U1531107,61627802). （Nos.U1531107,61627802）
