Antennas

What is an antenna?
Related wiki page: Feedlines

Antennas are electrical circuits. What makes them different from most circuits is that they are designed to facilitate the release of electromagnetic radiation. This occurs because the dimensions of the antenna are significant compared to the wavelength of operation, whereas in a conventional circuit, the dimensions of the components are very small compared to the wavelength of operation. So, antennas are specifically designed to release as much electromagnetic radiation as possible, whereas most circuits are designed to emit as little as possible

In terms of their construction, antennas are LCR circuits in which the Resistance, Inductance and Capacitance are distributed along a conductor, rather than being concentrated in a particular component such as an inductance in an inductor.

Antenna Types
Simple Antennas:

Dipole

Omnidirectional

Random Wire

Vertical

Wire

Complex Antennas:

Beam

DDRR

Dish or Parabola

Log Periodic (LPDA)

Yagi

Specialized Antennas:

DF - Direction Finding

Mobile

Panel

Portable

Understanding Antennas
UNDERSTANDING ANTENNAS FOR THE NON-TECHNICAL HAM