Design of Compact UWB Planar Monopole Antennas for Cross-Hole Radar Application

Printed rectangular antennas with a relatively small width (less than 60 cm) have been specifically designed to serve in a cross-hole radar for soil characterization in the frequency band [0.5; 1.5] GHz. Antenna geometries, including coplanar waveguide or microstrip line feed lines, have been optimized to show a low
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11 when inserted in an air-filled borehole surrounded by a high dielectric soil supposed to be wet in a practical situation.