Whip antenna
From Wikipedia, the free encyclopedia
 |
Please help improve this article or section by expanding it. Further information might be found on the talk page or at requests for expansion. |
A whip antenna is the most common example of a monopole antenna, an antenna with a single driven element and a ground plane.
The whip antenna is a stiff but flexible wire mounted, usually vertically, with one end adjacent to a ground plane. The whip antenna can also be called a half-dipole antenna, and as such, has a toroidal radiation pattern where the axis of the toroid centers about the whip. The length of the whip determines its wavelength, although it may be shortened with a loading coil anywhere along the antenna. Whips are generally a fraction of their actual operating wavelength, with half-wave and quarter-wave whips being very common. These antennas are widely used, especially for mobile applications and hand-held radios. They are usually attached to a vehicle and designed to be flexible, so that they don't break when struck; their name is derived from their whip-like motion when disturbed.
Being vertically mounted causes the whip antenna to have vertical polarization. Whips are thought of as omnidirectional, because they radiate equally in all directions in a horizontal plane, although they have a conical blind zone directly above them.
