Tunable Multiband Plasma Antenna Based on Toroidal Dipole

Abstract

The fractal antenna features space-filling and self-similarity properties to reduce the physical size. However, possible practical applications of these antennas have remained non-adjustable. Here, we realize the tunable multiband antenna with five operating windows facilitated by toroidal dipole, which is rarely observed in the antenna design. It consists of a half-wavelength antenna and eight plasma rings to excite the toroidal dipole, one of the counterparts of electromagnetic properties of matter, with current flowing in plasma to enhance the electromagnetic radiation of the whole antenna system, which is superior to conventional antenna with three or four working bands. We further confirm that the hybrid mode of toroidal dipole and multipole moments can be actively tuned to determine the return loss and the appearance of operating windows. Furthermore, the proposed antenna is stable in dusty plasma, making it suitable for solving the problem of “blackout” phenomena in aerospace communications, which exhibits the additional benefits of reduced cost and easier to manufacture.

Keywords: tunable multiband antenna, toroidal dipole, hybrid mode