Analytical and Numerical Study of a Gaseous Plasma Dipole in the UHF Frequency Band

Gaseous plasma antennas are appealing in applications in which reconfigurability is desired, because the radiation properties can be changed by tuning the plasma parameters. In this paper, an analytical and numerical analysis of a gaseous plasma dipole that works in the 0.3-3 GHz frequency range is presented; the plasma dipole is comprised of two discharges that are arranged similar to the arms of a center-fed metallic dipole. The analytical approach can provide the short- and open-circuit resonance frequencies of the plasma dipole, which have been proven reconfigurable by adjusting the discharge length and by adjusting the density of the plasma therein. Thanks to the numerical approach, the role of the type and pressure of the neutral gas species, and the magneto-static field on the reflection coefficient, and the gain function has been investigated. Finally, a feasibility study of an actual plasma dipole is presented; specifically, the choice of coupling the signal to be radiated by means of electrodes immersed in the plasma is a key to achieve radiation efficiency close to 90%.