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Encyclopedia > Driven element

In a mutually coupled antenna array (notably a Yagi-Uda antenna), the driven element is the single antenna that has an applied source feed. The other antenna elements are not excited (or driven). There are a few resons why one would only drive one element of the array. Doing this in the manner of a Yagi-Uda array allows for the field patterns to be directed in one direction with increased gain. The other elements are parasitic and take advantage of mutual coupling to aim the antenna. In biology, antenna (plural: antennae) refers to the sensing organs of several arthropods. ... A giant phased-array radar in Alaska In telecommunication, a phased array is a group of antennas in which the relative phases of the respective signals feeding the antennas are varied in such a way that the effective radiation pattern of the array is reinforced in a desired direction and... A yagi antenna A Yagi-Uda Antenna, commonly known simply as a Yagi antenna, is a antenna consisting of an array of a dipole and additional parasitic elements. ... A source is one of the components of communication and information processing. ... Electronics In electronics, gain is usually taken to meaning the ratio of the signal output of a system to the signal input of the system. ... An electric circuit, or electrical network, consists of electrical elements or components connected by conductors. ... Generally, coupling means a mechanical connection between two things. ...


In a log periodic dipole array (LPDA), only one of the many dipoles is driven at a time. The dipole that is driven depends on the frequency of the signal. The advantage of this over an antenna such as a Yagi, which is only designed for one frequency, is that the antenna can be made relatively broadband (nearly 2:1), by exciting differently sized elements that are resonant at different frequencies. Sources Federal Standard 1037C MIL-STD-188 Categories: Telecommunications stubs | Radio frequency antenna types ... This article is about the electromagnetic phenomenon. ... Sine waves of various frequencies; the lower waves have higher frequencies than those above. ... A signal may refer to: an abstract element of information, or, more exactly, usually a flow of information (in either one or several dimensions). ... Broadband in general refers to data transmission where multiple pieces of data are sent simultaneously to increase the effective rate of transmission. ... This article is about resonance in physics. ...


Notes

When a "driven element" is referred to in an antenna array, it is assumed that other elements are not driven (i.e. parasitic) and that the array is tightly coupled (spacing far below a wavelength). It is also possible to have multiple driven elements in an array. The wavelength is the distance between repeating units of a wave pattern. ...

  • For example, a two element array spaced a quarter wavelength apart has a distinct cardioid pattern when the second element is driven with a source -90 degrees out of phase relative to the source of the first element.
In geometry, the cardioid is an epicycloid which has one and only one cusp. ... Phase, from the Greek phasis, meaning appearance, has a number of related meanings in English. ...

  Results from FactBites:
 
Driven element - Wikipedia, the free encyclopedia (271 words)
In a mutually coupled antenna array (notably a Yagi-Uda antenna), the driven element is the single antenna that has an applied source feed.
The dipole that is driven depends on the frequency of the signal.
For example, a two element array spaced a quarter wavelength apart has a distinct cardioid radiation pattern when the second element is driven with a source -90 degrees out of phase relative to the source of the first element (see also phased array).
  More results at FactBites »

 
 

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