RESONANCE EFFECTS IN SLOTTED SPHERICAL ANTENNAS COATED WITH HOMOGENEOUS MATERIALS.

Radiation from a perfectly conducting slotted sphere coated with a homogeneous material is investigated. It is found that for some values of the coating thickness certain modes become resonant, which greatly enhance the radiated power and affect the radiation field. The enhancement in the radiated power, however, depends on the loss tangent of the coating material and reduces rapidly as the loss tangent increases.