Encyclopedia > Attenuation

  Article Content

Attenuation

1. In biology, attenuation is a mechanism in the regulation of gene expression

2. In ecology and geochemistry, attenuation is the ability to withhold contaminants in soils and groundwaters by various mechanisms like adsorption, dilution[?], dispersion or biological degradation, causing a lower toxicity compared to the total amount of the contaminant.

3. In telecommunication, attenuation is the decrease in intensity of a signal, beam, or wave as a result of absorption of energy and of scattering out of the path to the detector, but not including the reduction due to geometric spreading.

Note 1: Attenuation is usually expressed in dB.

Note 2: "Attenuation" is often used as a misnomer for "attenuation coefficient[?], " which is expressed in dB per kilometer.

Note 3: A distinction must be made as to whether the attenuation is that of signal power or signal electric field strength.

Source: from Federal Standard 1037C and adapted from the Department of Defense Dictionary of Military and Associated Terms



All Wikipedia text is available under the terms of the GNU Free Documentation License

 
  Search Encyclopedia

Search over one million articles, find something about almost anything!
 
 
  
  Featured Article
Monaco Grand Prix

... the narrow streets make it near-impossible to overtake on the track. However, its history and the spectacle of the event are likely to guarantee the event's future for ...

 
 
 
This page was created in 32.6 ms