From Wikipedia, the free encyclopedia.
A whip antenna is an antenna (electronics) with a single driven element and a ground plane. These antennas are very common, especially for mobile applications. These antennas are usually attached to a vehicle and designed to be flexible, so that they don't break when struck. These antennas derive their name from the whip-like motion they exibit during transit.
A whip antenna is a stiff, yet flexible, wire (almost always) mounted vertically, and attached at one end 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. Whips are generally a fraction of their actual operating wavelength, half-wave, and quarter-wave whips are very common.
Being vertically mounted causes the whip antenna to have vertical polarization. Whips are thought of as omni-directional, because they radiate equally in all directions when viewed from above, however whips are less receptive to signals directly above them.
Related concepts: Antenna theory
