Frequency, Moisture, and Density Dependence of the Dielectric Properties of Small Grains and Soybeans

ABSTRACT NEW data are presented on the dielectric properties of spring barley and oats, hardy and semihardy winter barley, soft red winter wheat, winter rye, and soybeans. Curves are shown for the dielectric constants and loss factors of each commodity at 24° C and frequencies of 20, 300, and 2450 MHz over moisture content ranges from about 8% to 25%, wet basis. In addition, mathematical models are summarized for these commodities and for shelled, yellow-dent field corn and hard red winter wheat, which estimate the dielectric constants as functions of moisture content, frequency, and bulk density of the grains and soybeans.