Directional antenna - Citizendia

Log-periodic dipole array

A directional antenna or beam antenna is an antenna which radiates greater power in one or more directions allowing for increased performance on transmit and receive and reduced interference from unwanted sources. An antenna is a Transducer designed to transmit or Receive electromagnetic waves In other words antennas convert electromagnetic waves into Directional antennas like yagi antennas provide increased performance over dipole antennas when a greater concentration of radiation in a certain direction is desired. A Yagi-Uda Antenna, commonly known simply as a Yagi antenna or Yagi, is a Directional antenna system consisting of an array of a dipole A dipole antenna, developed by Heinrich Rudolph Hertz around 1886, is an antenna with a center- fed Driven element for transmitting

All practical antennas are at least somewhat directional, although usually only the direction in the plane parallel to the earth is considered, and practical antennas can easily be omnidirectional in one plane. An omnidirectional antenna is an antenna system which radiates power uniformly in one plane with a directive pattern shape in a perpendicular plane

The most common types are the yagi antenna, the log-periodic antenna, and the corner reflector, which are frequently combined and commercially sold as residential TV antennas. A Yagi-Uda Antenna, commonly known simply as a Yagi antenna or Yagi, is a Directional antenna system consisting of an array of a dipole In Telecommunication, a log-periodic antenna ( LP, also known as a log-periodic array) is a Broadband, multielement A corner reflector is a Retroreflector consisting of three mutually perpendicular intersecting flat surfaces which reflects Electromagnetic waves back towards the Cellular repeaters often make use of external directional antennas to give a far greater signal than can be obtained on a standard cell phone. A cellular repeater, cell phone repeater, or wireless cellular signal booster, a type of bi-directional amplifier (BDA as commonly munications industry

For long and medium wavelength frequencies, tower arrays are used in most cases as directional antennas. A tower array is an arrangement of multiple Radio towers which are Mast radiators in a Phased array.

In Telecommunications and Radar, a Cassegrain antenna is an antenna in which the feed radiator is mounted at or near the surface of a concave The Cassegrain reflector is a combination of two coaxial reflectors used in Cassegrain telescopes and radio antennas First developed in 1672 by Laurent Cassegrain The high-gain antenna (HGA is an antenna with a focused narrow radiowave beam width A loop antenna has a continuous conducting path leading from one conductor of a two-wire transmission line to the other conductor The parabolic antenna is a high-gain reflector antenna used for radio television and data communications and also for radiolocation ( RADAR) on the UHF and An omnidirectional antenna is an antenna system which radiates power uniformly in one plane with a directive pattern shape in a perpendicular plane In Telecommunications the term directive gain has the following meanings 1 A "cantenna" is also a brand name for a Dummy load. A cantenna is a directional Waveguide antenna for long-range Cardioid is Closed curve with one Cusp. Definition In Geometry, the cardioid is an Epicycloid with one Cusp.

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