Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7147710 | Sensors and Actuators B: Chemical | 2014 | 10 Pages |
Abstract
By introducing wavelet-denoising (WD) in the traditional tunable diode laser absorption spectroscopy (TDLAS), a novel CH4 detection device based on WD-assisted wavelength modulation technique was experimentally demonstrated. Formulation and detection procedure were presented, and experiments were carried out to prove the normal function on the extraction of 2f signal from severely polluted differential signal with WD algorithm. With the fabricated device, sensing characteristics were measured on CH4 concentration. The response time is less than 8Â s within the whole detection range of 0-50Â kppm. By virtue of the suppression on noises with WD, the minimum detection limit (MDL) is dropped from 4 to 1Â ppm, the maximum detection error is minimized from 6.2% to 3.8% over the concentration range of 4-50Â kppm, and the decreased Allan deviation (per an average observing time of 9Â min for 24Â h) from 0.13 to 0.08Â ppm suggests enhanced stability. The proposed device also exhibits improved performances compared with our previously reported sensors based on simple direct spectroscopy absorption (DSA) technique and wide-band incandescence wire-source.
Related Topics
Physical Sciences and Engineering
Chemistry
Analytical Chemistry
Authors
Chuan-Tao Zheng, Wei-Lin Ye, Jian-Qiang Huang, Tian-Shu Cao, Mo Lv, Jing-Min Dang, Yi-Ding Wang,