A second fundamental distinguishing feature is that
after sending a pulse the plasma antenna can be deionized, eliminating
the ringing associated with traditional metal elements. Ringing
and the associated noise of a metal antenna can severely limit
capabilities in high frequency short pulse transmissions. In these
applications, metal antennas are often accompanied by sophisticated
computer signal processing. By reducing ringing and noise, we
believe our plasma antenna provides increased accuracy and reduces
computer signal processing requirements. These advantages are
important in cutting edge applications for impulse radar and high-speed
Based on the results of development to date, plasma
antenna technology has the following additional attributes:
No antenna ringing provides an improved signal to noise
ratio and reduces multipath signal distortion.
· Reduced radar cross section provides stealth due to the non-metallic
· Changes in the ion density can result in instantaneous changes
in bandwidth over wide dynamic ranges.
· After the gas is ionized, the plasma antenna has virtually no
· While in operation, a plasma antenna with a low ionization level
can be decoupled from an adjacent high-frequency transmitter.
· A circular scan can be performed electronically with no moving
parts at a higher speed than traditional mechanical antenna structures.
· It has been mathematically illustrated that by selecting the
gases and changing ion density that the electrical aperture (or
apparent footprint) of a plasma antenna can be made to perform
on par with a metal counterpart having a larger physical size.
· Our plasma antenna can transmit and receive from the same aperture
provided the frequencies are widely separated.
· Plasma resonance, impedance and electron charge density are
all dynamically reconfigurable. Ionized gas antenna elements can
be constructed and configured into an array that is dynamically
reconfigurable for frequency, beamwidth, power, gain, polarization
and directionality - on the fly.
· A single dynamic antenna structure can use time multiplexing
so that many RF subsystems can share one antenna resource reducing
the number and size of antenna structures.
To date, plasma antenna technology has been studied and characterized
by ASI Technology Corporation revealing favorable attributes in
connection with antenna applications. Government sponsored work
• ONR contract N66001-97-M-1153 May 1997 - The major
objective of this program was to determine the noise levels associated
with the use of gas plasma as a conductor for a transmitting and
receiving antenna. Both laboratory and field-test measurements
• ONR contract N00014-98-C-0045 November 1997 - The
major objective of this effort was to characterize the GP antenna
for conductivity, ionization breakdowns, upper frequency limits,
excitation and relaxation times, ignition mechanisms, temperatures
and thermionic noise emissions and compare these results to a
reference folded copper wire monopole. The measured radiation
patterns of the plasma antenna compared very well with copper
• MDA Phase I SBIR Contract DASG60-01-P-0063 May 2001
- This six month work (expanded for an additional three months
by MDA) focused on using plasma rather than solid metal as the
current medium for an antenna. We illustrated the use of controllable
apertures (open plasma windows) for far field antenna radiation.
Experiments verified our plasma windowing concept.
• MDA Phase II SBIR Contract DASG60-02-C-0055 April
2002 - This 24 month contract is focusing on developing a feasibility
prototype high power antenna based on our windowing concept and
to design and develop a high power phased array using plasma phase
shifters to steer the beam. Malibu Research Associates is our
subcontractor on this project.
• MDA Phase I SBIR Contract DASG60-02-P-0033 April
2002 - This 6 month contract focused on using plasma as a replacement
for metal in a frequency selective surface (FSS) used to filter
electromagnetic waves. A tunable FSS can absorb frequencies above
the resonant frequency and reflect those above to reduce radar
vulnerability to countermeasures. Plasma is an excellent shield
and filter for antenna systems.