مرکز منطقه ای اطلاع رساني علوم و فناوري

Abstract :

Results of an experiment to determine the feasibility of monitoring corn growth with radar are reported. Radar backscattering data were acquired with a ground based 8-18 GHz radar spectrometer during the summer of 1974. Supporting ground truth data were also collected. During the month of July the crop suffered from a water deficit, although by no means was the crop destroyed by this lack of moisture. At angles of incidence of $40\\deg$ or greater, the results of the data analysis indicate a strong correlation between the radar backscattering coefficient $\\sigma \\deg$ and the "normalized plant water content" $W_{pn}$ , where $W_{pn}$ is the mass of water in the corn plant divided by its height. The correlation coefficient between $\\sigma \\deg$ and $W_{pn}$ , which was calculated for each of 176 different combinations of the radar parameters (signal frequency, angle of incidence and polarization), was highest (0.96) at 17.0 GHz, $50\\deg$ VV polarization. Considering the fact that the data used covered a period of four months during which the corn plants underwent considerable change in geometry and dielectric properties, the high correlation of 0.96 between $\\sigma \\deg$ and $W_{pn}$ points to a promising future for radar as a tool for monitoring corn development.