THEORETICAL INCREASE IN RADIATION EFFICIENCY OF A SMALL DIPOLE ANTENNA MADE WITH A HIGH-TEMPERATURE SUPERCONDUCTOR

An electrically small wire dipole antenna with a shunted stub matching network has been analyzed to determine the improvement in radiation efficiency that can be achieved by making the metallic components from high temperature superconducting (HTS) material. The analysis shows that significantly higher radiation efficiencies can be obtained with HTS material only if the dielectric losses are kept at very low values. A loss tangent of less than 10-4 is necessary for any dielectric materials in the transmission lines and support structures for the antenna; a loss tangent of at least 10-5 is desirable, particularly if the dipole length is 0.1 wavelength or less. © 1990 IEEE