2.3. Antenna Types

2.3.1. Wire Antennas

Short Dipole

The simplest of all antennas. It is simply an open-circuited wire, fed at its center The words “short” or “small” imply “relative to a wavelength” size of the dipole antenna does not matter.



Two monopoles facing away from each other Used to greate a powerful signal in restricted space


Half-Wave Dipole

Special case of the dipole antenna Length of this dipole antenna is equal to a half-wavelength


Broadband (Wideband) Dipoles

Broadband by increasing the radius A of the dipole


Monopole (Whip)

Works best for narrow range and can be collapsible Used on small radios and vehicles


Folded Dipole

Folded dipole forms a closed loop



Works like a dipole and reach multiple frequencies. Commonly used for TV and RFID systems



Circularly polarized wire antenna, with a radiation pattern similar to a dipole antenna peak radiation direction broadside to the antenna. The antenna has nulls (very little radiation) in the axial direction


2.3.2. Log-Periodic Antennas

Bow Tie

Another type of dipole. Angles can be set to work well with different frequencies. Similar radiation pattern to the dipole antenna, and will have vertical polarization

Log-Periodic Tooth ../_images/at-LPtooth.gif
Log-Periodic Dipole Array (LPDA) ../_images/at-logperiodic.png

2.3.3. Aperture Antennas

Slot ../_images/at-slot.png
Cavity-Backed Slot ../_images/at-cavitybackedslot.png
Inverted-F ../_images/at-invertedf.png
Slotted Waveguide ../_images/at-slottedwaveguide.jpg
Horn ../_images/at-horn.png
Vivaldi ../_images/at-vivaldi.gif
Telescopes (Eye) ../_images/at-eye-antenna.gif

2.3.4. Travelling Wave Antennas

Helical ../_images/at-helical.jpg


Ideal for long distance directional applications Can reach multiple frequencies

Spiral ../_images/at-spiral.png

2.3.5. Reflector Antennas

Corner Reflector ../_images/at-corner.jpg
Parabolic Reflector (Dish) ../_images/at-dish.png

2.3.6. Microstrip Antennas

Rectangular Microstrip (Patch) ../_images/at-patch.png
Planar Inverted-F (PIFA) ../_images/at-printedinvertedf.png

2.3.7. Other Antennas

NFC ../_images/at-nfc.png
Fractal ../_images/at-fractal.png
Wearable ../_images/at-wearable.png