Plasma antennas are stealthy, versatile, and jam resistant

Published 14 November 2007

Soldiers in the field would soon benefit from a new antenna made of plasma — that is, a gas heated to the point at which the electrons are ripped free of atoms and molecules) works just like conventional metal antennas, except that it vanishes when you turn it off

What do soldiers on the battlefield want from their antennas? Simple: That it be kept out of site and that the enemy will not be able to jam it. Plasma antennas are the answer. They behave much as solid metal antennas do because electrons flow freely in the hot gas, just as they do in metal conductors. The difference is that plasmas only exist when the gasses they are made of are very hot. The moment the energy source heating a plasma antenna is shut off, the plasma turns back into a plain old — and non conductive — gas. This means that as far as radio signals and antenna detectors go, the antenna effectively disappears when the plasma cools down.

The antenna design is being presented this week at the 49th annual meeting of the American Physical Society’s (APS) Division of Plasma Physics meeting in Orlando, Florida. The design consists of gas-filled tubes reminiscent of neon bulbs. The physicists presenting the design propose that an array of many small plasma elements could lead to a versatile antenna that could be reconfigured simply by turning on or off various elements.