A Modified Open-Ended Probe as a Reliable Tool for Measurements of Soil Water Content

The work presents the test results of the performance of an open-ended probe with an antenna (OE-A) as an appropriate tool for the measurement of the water content in soil. The measurement volume of OE-A is larger compared to a classical coaxial open-ended (OE) probe, making the considered probe applicable in agrophysics. To correctly assess the reliability of the probe, both numerical simulations and measurements were done. Two types of the mineral soils with different moisture were analyzed in the frequency range 1 MHz - 6 GHz using vector network analyzer (VNA) one port (reflective) measurements.