Multifrequency emission of wheat: Modeling and applications

The microwave brightness temperatures of a wheat field were measured in 1993, during the whole growth cycle by the six-frequency PORTOS radiometer, at two polarizations and several angles. In this paper, the emissivities measured at L-, C-, X-, and K-band are compared with those simulated by a discrete multiple scattering model based on the radiative transfer theory. The agreement between experimental and simulated data is generally good at all frequencies, although a unique set of input parameters has been used. It is demonstrated that the model simulations lead to a reliable identification of the radiometric configurations most sensitive to ground variables. Moreover, they aid the development of a soil moisture inversion algorithm that performs well even with soils covered by developed vegetation.