COMPARISON OF THE SOIL MOISTURE OBTAINED DIRECTLY FROM RADIOMETER AND THE ESTIMATED SOIL MOISTURE FROM MEASURED DIELECTRIC CONSTANT

The emissivity of dry and wet soil depends on dielectric constant, surface roughness, physical properties, polarization and the angle of incidence of microwaves. This study shows the comparison of emissivity obtained from ground-based radiometer with the estimated value from measured dielectric constant. The dielectric constant of dry and wet soil is measured using waveguide cell method at different physical temperatures and emissivity is estimated. A radiometer is used to obtain the emissivity from brightness temperature and physical temperature for variable angle of incidence and both polarization. This study will provide methodology for validation of sensor data with ground-based measurements