Engineering Frontiers
Josh Ianacone
Overview
 Background
 How Antennas Work
 Characteristics
 Current Technology
 Introduction
 Plasma Antennas
 Advantages
 Plasma vs Traditional
 Experiments
 Applications
 Communications
 Military
 Conclusion
[11]
Background
 Since the discovery of radio frequency ("RF") transmission
 Antenna design is an important part of almost all
communication and radar applications
 Technology has advanced to provide unique antenna
designs
 Broadcast of radio frequency signals for public
 Complex weapon systems
 Antennas Defined:
 An electrical conductor of a specific length that radiate radio
waves generated by a transmitter and collect waves at the
receiver
How Antennas Work
Generate Waves
 Antennas generally made of metals
 Metals act like containers filled
with a liquid made of electrons
 Radio and TV waves
 Make electrons oscillate up and down
on an antenna
 Applying a variable voltage or
alternating current to the antenna
[12]
Characteristics
 The size and shape of an antenna depend:
 Frequency on which the antenna will transmit and receive
 Direction of the radiated electromagnetic wave
 Power with which the antenna must transmit
 The size of an antenna is inversely proportional to the
wavelength of the signal it is designed to transmit or receive.
 Lower frequency signals require larger antennas.
Wavelength (l) = C/f
 Where C= speed of light (3 x 108 m/s),f = frequency
 Antenna waves move at the speed of light so fast travel time
[5]
TX/RX
 All radios, whether transmitting or receiving, require
some sort of antenna
[13]
Current Technology
Traditional Antennas
 Generally employs solid metal wires as the conducting
element
 Experiences ringing and the associated noise of a
metal antenna
 Severely limits capabilities in high frequency short pulse
transmissions
 Metal antennas are often accompanied by
sophisticated computer signal processing
 To deal with these problems a new technology is being
developed
Plasma Antennas
Plasma
 Fourth state of matter
 Also most common form of matter
 Over 99% of the visible universe
 Identified by Sir William Crookes, an English
physicist, in 1879
 The word "PLASMA" was first applied to ionized gas
by Dr. Irving Langmuir, an American chemist and
physicist, in 1929.
 Plasmas carry electrical currents and generate
magnetic fields.
 Cold Plasma is used for antenna applications
Chemistry
 Plasma consists of a collection of free moving electrons
and ions (atoms that have lost electrons)
[13]
Plasma Antenna
 An RF antenna based on a plasma element instead of metal
conductor
 Plasma antenna technology employs ionized gas
enclosed in a tube (or other enclosure) as the
conducting element of an antenna
 When gas is electrically charged, or ionized to a
plasma state it becomes conductive
 Allowing radio frequency signals to be transmitted or received
 Ionized gas is an efficient conducting element with
several important advantages
Advantages
 Gas ionized only for the time of transmission or reception
 After sending a pulse the plasma antenna can be deionized
 “Ringing" and associated effects of solid wire antenna design are
eliminated.
 No antenna ringing means improved signal to noise ratio
 Antenna Design
 More efficient, lower in weight and smaller in size than traditional
solid wire antennas.
 Design allows for extremely short pulses
 Important to many forms of digital communication and radars
 Provides the opportunity to construct an antenna
 Compact and dynamically reconfigured
 Frequency, direction, bandwidth, and gain
Key Features
 Higher power - Increased power can be achieved in the





plasma antenna than in the corresponding metal
Enhanced bandwidth - By the use of electrodes or lasers
the plasma density can be controlled
Higher Efficiency - higher due to lower Ohmic losses in
the plasma
Lower Noise - The plasma antenna has a lower collision
rate among its charge carriers than a metal antenna and
this means less noise
Smaller in Size
Low in Weight
Applications
 Weapons System Division has been studying the concept of
using plasma columns for antennas
 The plasma antenna's advantages over conventional metal
elements are most obvious in military applications where
stealth and electronic warfare are primary concerns
 The antenna is only energized for a very short time as
communication takes place
 Other important military factors are weight, size and the
ability to reconfigure
 Shipboard/submarine antenna replacements
 Unmanned air vehicle sensor antennas
Experiment
 Rajneesh Kumar1 and D. Bora
 Institute for Plasma Research
 Gandhinagar, India
 Experiment performed
 Show usefulness/versatility
of plasma antenna for communication
 Plasma column different gases
 argon, air, nitrogen and oxygen
 plasma density and temperature relatively
the same
 Changed external operating parameters
 plasma column is transformed to finite
number of cylindrical striations
Plasma column
35 cm long
3 cm diameter
[1]
Experiment
 These states are visibly different
 Shown in image
 It was observed that each of these
structures of plasma column
perform as antenna
 The number and length of the elements can be
 controlled by Input power, frequency, working pressure
and length of glass tube
 Different type of antenna structures formed in a single
system
 Changing the external parameters allows for a versatile
plasma antenna
[1]
Development
 Antenna Prototype
 T. R. Anderson and I. Alexeff
 Presented at APS Division of Plasma
Physics meeting in Orlando
 Physicists presenting:
 Propose that an array of
 Small plasma elements
 Lead to a highly versatile antenna
 Could be reconfigured simply by turning on or off
various elements
[14]
Other Prototypes
 The plasma antenna R & D project has proceeded over
the last year at the Australian National University
[15]
Available
 Plasma Sonics Ltd. Co.
 Specifications
 Glass - Pyrex
 Tube Length > 30"
 Tube Diameter - 25mm
 Mount Dimensions 12.5 inches X21 inches 11 inches
 Price: $ 380
[10]
Current Status
 To date, plasma antenna technology has been studied and
characterized by ASI Technology Corporation
 SelectaBeam SC-750 Series
 Major objective of their program
 determine the noise levels associated with the use of gas
plasma as a conductor for a transmitting and receiving
antenna.
 Plasma Physics Laboratory at the University of Tennessee,
 An inflatable plasma antenna is being developed
 The idea of Plasma Silicon Antenna (PSiAN) is being
introduced
 Uses thousands of diodes on a silicon chip
 Diode generates a cloud of electrons
Review
 Technology Currently being development
 Could greatly impact future of communications
 Sensing, Defense, Space and Homeland security
 Effectively invisible to radar
 Resistant to electronic warfare
 Reconfigurable
 Replacing need for multiple antennas

Frequency, direction, bandwidth, gain
 Versatile
 Reduced size
 Better performance
Conclusion
 The gas plasma antenna conducts electron current like a
metal and hence can be made into an antenna but with
distinct advantages
 Fundamental change from traditional antenna
 Expect to see on the Market next 5 years
VS
References
Journals
[1]Kumar, Rajneesh; Bora, Dhiraj; , "A reconfigurable plasma antenna," Journal of Applied
Physics , vol.107, no.5, pp.053303-053303-9, Mar 2010
[2] Xue-Shi Li; Fan Luo; Bin-Jie Hu; , "FDTD Analysis of Radiation Performance of a Cylinder
Plasma Antenna," Antennas and Wireless Propagation Letters, IEEE , vol.8, no., pp.756758, 2009 doi: 10.1109/LAWP.2009.2022963
[3] Kumar, R. (2011). Communication capability of a reconfigurable plasma antenna. Journal
of applied physics, 109(6), 2011 063303-063303-9.doi:10.1063/1.3564937
Others
[ 4]Zhaoyang Dai; Shaobin Liu; Yu Chen; Nan Gao; , "Development and investigation of
reconfigurable plasma antennas," Microwave and Millimeter Wave Technology (ICMMT),
2010 International Conference on , vol., no., pp.1135-1137, 8-11 May 2010
[5]http://www.associatedcontent.com/article/7693306/gas_plasma_antennas_next_step_in
_high.html
[6]Cerri, G.; Russo, P.; Vecchioni, E.; , "Electromagnetic characterization of plasma
antennas," Antennas and Propagation, 2009. EuCAP 2009. 3rd European Conference on ,
vol., no., pp.3143-3146, 23-27 March 2009
[7 ]http://www.plasmas.org/what-are-plasmas.htm
[
References
 [8]http://www.essortment.com/plasma-fourth-state-matter-40444.html
 Images
 [9] http://intuitor.com/resonance/radioTVres.html
Images
 [10] http://www.plasmasonics.com/tube.html
 [11]http://www.explainthatstuff.com/antennas.html
 [12]http://www.armymars.net/ArmyMARS/Antennas/Resources/usmcantenna-hb.pdf
 [13] http://www.scribd.com/doc/26987365/Plasma-Antenna-New
 [14] http://www.physorg.com/news114098443.html