Confined plasma resonance antenna and plasma resonance antenna array
AssigneeThe United States of America as represented by the Secretary of the Navy
InventorTheodore R. Anderson
Life of this patent
Estimating the term…
Abstract
A plasma antenna includes a plasma column formed of an ionizable gas. A modulating carrier frequency produces Hertzian dipoles within the plasma that radiate RF energy at the modulating carrier. The antenna, which produces these dipoles, can be short and still produce significant gain when the modulating carrier frequency and the natural resonance frequency of the plasma are substantially equal. Other aspects of the invention include a method to produce such plasma antenna and a product by process embodiment of the plasma antenna.
Claims18
A method for producing a confined plasma column type antenna, comprising:
- providing an elongated pressure vessel made of nonconductive material which has a longitudinal axis;
- providing a pair of electrodes within said pressure vessel, which respectively are disposed at one and the other of opposite ends of the pressure vessel;
- introducing into and confining within said pressure vessel an ionizable gas which in its ionized state in said pressurized vessel has a predetermined pre-adjusted natural resonance frequency;
- to cause the ionizable gas to be in its ionized state concurrently applying a dc potential across the electrodes and an ac electric field to the column of gas within the elongated pressure vessel, said electric field being applied to said column of gas along the longitudinal axis, said ac electric field having a frequency essentially corresponding to said pre-adjusted tuned natural resonance frequency;
- and
- adjusting the potential applied across the electrodes to further tune the natural resonance frequency of the confined plasma column antenna to reduce the difference between said pre-adjusted natural resonance frequency and the frequency of said ac electric field applied to the antenna to tune said confined column of gas for increased gain as an antenna.
Confined plasma column antenna apparatus for radiating of energy comprising:
- an elongated pressure vessel made of non-conductive material having a longitudinal axis;
- a pair of electrodes disposed within said pressure vessel which respectively are disposed at opposite ends of the pressure vessel;
- an ionized gas confined within said pressure vessel having a predetermined characteristic pre-adjusted tuning natural resonance frequency;
- a gas ionization implementation dc source and a gas ionization implementation ac modulator, said dc source and said ac modulator cooperatively coacting to ionize the gas confined within said elongated pressure vessel to provide ionization of the gas in the pressure vessel;
- said ionization implementation dc source applying a dc potential across said electrodes;
- said gas ionization implementation ac modulator being operative to apply an ac electric field to the column of gas within the elongated pressure vessel, said ac electric field having a frequency essentially corresponding to said pre-adjusted natural resonance frequency, said electric field being applied to the column of gas along said longitudinal axis;
- said gas ionization implementation dc source further being of a type which enables selective adjustment of the dc potential across the electrodes;
- and
- said confined column plasma antenna being tuned for gain through an adjustment of the dc potential applied across said electrodes to reduce the difference between the pre-adjusted natural resonance frequency and the frequency of the ac electric field applied by the gas ionization implementation ac modulator.
Dependencies are inferred from the claim text.