WATER CONTENT, SALINITY AND TEXTURE SENSOR OF POROUS MEDIA

摘要

A sensor for measuring water content, salinity and texture of a soil or any other porous medium by measuring the permittivity and conductivity of the soil in the frequency domain. A microprocessor-controlled oscillator generates a high frequency sinusoidal signal that is injected in a probe buried in the soil to be measured. The relationship between the permittivity and conductivity of a soil and the velocity and attenuation of a signal travelling in it being known, the invention discloses a novel way to measure the velocity of the signal by comparing the phase of the signal entering the probe with the phase of the signal exiting, and the attenuation by comparing their amplitudes.