06-07-2012, 04:06 PM
ANTENNA ENGINEERING
[attachment=27004]
INTRODUCTION
Antenna or Aerial :
- is a transducer that transmits or receives
electromagnetic waves
- converts the voltage and current into the
electromagnetic radiation and vice-versa
- is a transitional structure between free-space and a
guiding structure
- The American Heritage Dictionary: A metallic
apparatus for sending and receiving electromagnetic
waves.
- Webster’s Dictionary: A usually metallic device (as a
rod or wire) for radiating or receiving radio waves
Wire antennas
seen virtually everywhere- on automobile,
building, ships, aircraft, and so on.
Shapes of wire antennas:
straight wire (dipole), loop (circular), and helix,
Loop antenna may take the shape of a rectangle ,
ellipse or any other shape configuration
Aperture-antenna
Aperture antennas derived from waveguide technology (circular, rectangular)
Can transfer high power (magnetrons, klystrons)
Microstrip antenna
consist of metallic patch on a grounded substrate
Examples: rectangular and circular shape
Applications: aircraft, spacecraft, satellite, missiles, cars etc
[attachment=27004]
INTRODUCTION
Antenna or Aerial :
- is a transducer that transmits or receives
electromagnetic waves
- converts the voltage and current into the
electromagnetic radiation and vice-versa
- is a transitional structure between free-space and a
guiding structure
- The American Heritage Dictionary: A metallic
apparatus for sending and receiving electromagnetic
waves.
- Webster’s Dictionary: A usually metallic device (as a
rod or wire) for radiating or receiving radio waves
Wire antennas
seen virtually everywhere- on automobile,
building, ships, aircraft, and so on.
Shapes of wire antennas:
straight wire (dipole), loop (circular), and helix,
Loop antenna may take the shape of a rectangle ,
ellipse or any other shape configuration
Aperture-antenna
Aperture antennas derived from waveguide technology (circular, rectangular)
Can transfer high power (magnetrons, klystrons)
Microstrip antenna
consist of metallic patch on a grounded substrate
Examples: rectangular and circular shape
Applications: aircraft, spacecraft, satellite, missiles, cars etc