Title :
Measurements of leaf water content using terahertz radiation
Author :
Hadjiloucas, Sillas ; Karatzas, Lucas S. ; Bowen, John W.
Author_Institution :
Dept. of Cybern., Reading Univ., UK
fDate :
2/1/1999 12:00:00 AM
Abstract :
A novel technique for the noninvasive continuous measurement of leaf water content is presented. The technique is based on transmission measurements of terahertz radiation with a null-balance quasi-optical transmissometer operating at 94 GHz. A model for the propagation of terahertz radiation through leaves is presented. This, in conjunction with leaf thickness information determined separately, may be used to quantitatively relate transmittance measurements to leaf water content. Measurements using a dispersive Fourier transform spectrometer in the range of 100 GHz-500 GHz using Phormium tenax and Fatsia japonica leaves are also reported
Keywords :
Fourier transform spectroscopy; biological techniques; biological tissues; botany; electromagnetic wave transmission; millimetre wave measurement; millimetre wave spectroscopy; moisture measurement; osmosis; submillimetre wave measurement; submillimetre wave spectroscopy; 100 to 500 GHz; 94 GHz; Fatsia japonica leaves; IMPATT oscillator; Jones matrix analysis; Mach-Zehnder interferometer; Martin-Puplett interferometer; Phormium tenax leaves; dispersive Fourier transform spectrometer; hybrid interferometer; leaf osmotic potential; leaf thickness; leaf water content; noninvasive continuous measurement; null-balance quasi-optical transmissometer; pseudocoherence; terahertz radiation; transmission measurements; Dispersion; Electromagnetic measurements; Fourier transforms; Laboratories; Magnetic field measurement; Spectroscopy; Stress; Submillimeter wave measurements; Submillimeter wave propagation; Thickness measurement;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
