Presented by:
SUNEEL MADDHESHIA

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INTRODUCTION
Plasma Antenna is a special type of antenna in which the metal conducting elements of a conventional antenna are replaced by a plasma.
PLASMA
Fourth state of matter similar to gas.
Sir William Crookes, an English Physicist identified it in 1879.
According to Markland’s technology, plasmas are conductive assemblies of charged and neutral particles and fields that exhibit collective effects.
ANTENNA
It is defined as an electrical conductor of a specific length that radiate radiowaves generated by a transmitter and collect that waves at the receiver.
GENERATION OF ELECTRIC AND MAGNETIC FIELD
When voltage applied to an antenna,electric field produced.
Causes current to flow in antenna.
Due to current flow,magnetic field produced.
These two fields are emitted from an antenna and propagate through space over very long distances.
PLASMA ANTENNA TECHNOLOGY
It employs an ionized gas enclosed in a tube as the conducting element of an antenna.
When the gas is electrically charged or ionized to a plasma,it becomes conductive and allowing radio frequency signals to be transmitted or received.
When gas is not ionized,the antenna element ceases to exit.
IONIZED GAS PLASMA ANTENNA
FIGURE OF PLASMA TUBE ANTENNA
WORKING PRINCIPLE
When supply is given to the tube, the gas inside it gets ionised to plasma.
When plasma is highly energised, it behaves as a conductor.
Antenna generates a localised concentration of plasma to form a plasma mirror that deflects RF beam launched from a central feed located at focus of mirror.
WORKING PRINICIPLE FIGURE
PHYSICAL PROCESSES
A plasma jet has diameter ‘a’ is formed in the atmosphere and passes through a dielectric cylinder that has diameter ‘b’ and a conductive spiral is winded on the cylinder.
FIGURE OF PLASMA ANTENNA DESIGN:
OPERATION
When plasma jet enters into the spiral field, signals are emitted.
The spiral is a localised concentration of plasma.
These spirals behave as plasma mirrors which helps in transmission of RF signals.
APPLICATIONS
In highspeed digital communication and radar system.
In radio antenna.
Stealth for millitary application.
Used for transmission and modulation techniques(PM,AM,FM).
ADVANTAGES
Higher Power
Enhanced bandwidth
Higher efficiency
Lower noise
Perfect reflector
Low in weight
Smaller in size
Improved reliability
CONCLUSION
It is more advantageous than other antenna due to ionized gas.
Its action has many general with the dielectric antenna action.
It helps in pulse operation.