Application of Microwave Nonstationary Spectroscopy for Noninvasive Medical Diagnostics

We consider an application of the method of microwave nonstationary gas spectroscopy for analytical studies of multicomponent gas mixtures using exhaled air as an example. The methods used for studying multicomponent gas mixtures are reviewed. We describe subterahertz and terahertz nonstationary gas spectrometers based on the effect of freely damped polarization. The results of test measurements of nitric oxide (NO) in the 2-mm wavelength range are presented. Methods for studying the response dynamics are developed. The prospects of using the method of microwave nonstationary gas spectroscopy in the subteraherz and teraherz ranges are shown. __________ Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 51, No. 6, pp. 545–551, June 2008.