CST MICROWAVE STUDIO® (CST MWS) simulates this small dipole antenna in freespace finding the resonant frequency, drive-point impedance, radiation efficiency and total Q. Small antennas are defined by ka<0.5 which means the entire structure must fit inside a sphere with a radius less than 0.0796 wavelengths. In the case presented here, the entire antenna fits inside a sphere of radius 0.0415 wavelengths, ignoring wire diameter. (Model courtesy of Steven R. Best, Air Force Research Laboratory, Hanscom Air Force Base, USA)
The Perfect Boundary Approximation® (PBA) allows even curved surfaces to be simulated using a Cartesian grid. Sub-gridding enhances this feature by minimizing the number of mesh-cells needed for a structure that is made up entirely of 3-dimensional curves mirrored about the E-plane.
S. R. Best, "Low Q Electrically Small Linear and Elliptical Polarized Spherical Dipole Antennas," IEEE Transactions on Antennas and Propagation, Vol. 53, No. 3, pp. 1047-1053, March 2005.
S. R. Best, "The Radiation Properties of Electrically Small Folded Spherical Helix Antennas," IEEE Transactions on Antennas and Propagation, Vol. 52, No. 4, pp. 953-960, April 2004.