Feasibility of measurement of the dielectric properties for bulk density and moisture-content
determination in cereal grain and oilseed with inexpensive microstrip antennas in the near
field is discussed. Results obtained for wheat and soybeans with a pair of single-patch
microstrip antennas operating at 5.8GHz and 24C are compared to those taken in the
far field with a pair of focused-beam horn=lens antennas. The standard errors of calibration
calculated for bulk density and moisture-content prediction from measurement of the
dielectric properties in the near field are slightly higher than those corresponding to far-field
measurements but remain within an acceptable error range.
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