论文信息 - Chemical recognition of gases and gas mixtures with terahertz waves.

Chemical recognition of gases and gas mixtures with terahertz waves.

A time-domain chemical-recognition system for classifying gases and analyzing gas mixtures is presented. We analyze the free induction decay exhibited by gases excited by far-infrared (terahertz) pulses in the time domain, using digital signal-processing techniques. A simple geometric picture is used for the classif ication of the waveforms measured for unknown gas species. We demonstrate how the recognition system can be used to determine the partial pressures of an ammonia-water gas mixture.

[1] Daniel R. Grischkowsky,et al. Characterization of an optoelectronic terahertz beam system , 1990 .

[2] Richard G. Brewer,et al. Optical Free Induction Decay , 1972 .

[3] H. Müller,et al. Submillimeter, millimeter, and microwave spectral line catalog. , 1985, Applied optics.

[4] D. Grischkowsky,et al. Far-infrared terahertz time-domain spectroscopy of flames. , 1995, Optics letters.

[5] I. Brener,et al. Terahertz emission from electric field singularities in biased semiconductors , 1996, Summaries of papers presented at the Conference on Lasers and Electro-Optics.

[6] Grischkowsky,et al. THz commensurate echoes: Periodic rephasing of molecular transitions in free-induction decay. , 1991, Physical review letters.

[7] M. Nuss,et al. Subpicosecond photoconducting dipole antennas , 1988 .

[8] Biing-Hwang Juang,et al. Fundamentals of speech recognition , 1993, Prentice Hall signal processing series.

[9] J. Makhoul,et al. Linear prediction: A tutorial review , 1975, Proceedings of the IEEE.

[10] John G. Proakis,et al. Digital Signal Processing: Principles, Algorithms, and Applications , 1992 .

[11] D. Grischkowsky,et al. Terahertz time-domain spectroscopy of water vapor. , 1989, Optics letters.