  We have studied the behavior of a VLF, ELF and combined ELF/VLF antenna
immersed in a cold, magnetized plasma using a fully kinetic, three dimensional
Particle-in-Cell simulation code called Large Scale Plasma (LSP). All the
antennas are modeled as magnetic dipoles ($\rho_{ant}=0$) and are assigned a
time varying current density within a finite sized current loop. The VLF
antenna is driven at 10 Amps with a frequency ($\omega_{VLF}$) greater than the
lower hybrid frequency ($\omega_{LH}$), while the ELF antenna is driven at 3
Amps with a frequency ($\omega_{ELF}$) less than $\omega_{LH}$. The combined
ELF/VLF antenna (which we call a parametric antenna) includes both antennas
driven simultaneously in the same simulation domain. We show that the
parametric antenna non-linearly excites electromagnetic (EM) Whistler waves to
a greater extent than the VLF antenna alone. We also show that the parametric
excitation of EM Whistler waves leads to greater emitted EM power (measured in
Watts) compared with a VLF antenna alone.
