Horn
A horn is a pointed projection of the skin of various animals. In ruminant artiodactyls, the horns are paired and take various forms depending on the family:- Tragulidae: No horns.
- Antilocapridae: The horn has a prong.
- Giraffidae: There are bony bumps which look like they ought to have horns on them, but don't.
- Cervidae: Deer have antlers, which are made of bone and shed each year.
- Moschidae: ?
- Bovidae: The horns are made of horn (i.e. keratin) and are cones bent into spiral shapes.
In telecommunication, the term horn has the following meanings:
1. In radio transmission, an open-ended waveguide, of increasing cross-sectional area, which radiates directly in a desired direction or feeds a reflector that forms a desired beam.
Note 1: Horns may have one or more expansion curves, i.e. , longitudinal cross sections, such as elliptical, conical, hyperbolic, or parabolic curves, and not necessarily the same expansion curve in each (E-plane and H-plane) cross section.
Note 2: A very wide range of beam patterns may be formed by controlling horn dimensions and shapes, placement of the reflector, and reflector shape and dimensions.
2. A portion of a waveguide in which the cross section is smoothly increased along the axial direction.
3. In audio systems, a tube, usually having a rectangular transverse cross section and a linearly or exponentially increasing cross-sectional area, used for radiating or receiving acoustic waves.
Source: from Federal Standard 1037C and from MIL-STD-188
