Attenuation Coefficient

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attenuation coefficient

[ə‚ten·yə′wā·shən ‚kō·ə′fish·ənt]
The space rate of attenuation of any transmitted electromagnetic radiation.

Attenuation Coefficient


(or extinction coefficient), a quantity inverse to the distance at which the radiation flux forming a parallel beam is attenuated as a result of the joint action of the absorption and scattering of light in a medium by a specified factor. When the factor is 10, the coefficient is called the decimal attenuation coefficient, and when the factor is e, it is called the natural attenuation coefficient. The attenuation coefficient is the sum of the absorption coefficient and the scattering coefficient of the medium. These coefficients depend on the set of frequencies v, or wavelengths λ, that characterize the initial flux. The value of the attenuation coefficient for the limiting case of a single frequency v is called the monochromatic attenuation coefficient. Like the absorption and scattering coefficients, the attenuation coefficient can be divided by the volume of the medium or by the mass of the attenuating substance; we shall call these two ratios the volume and mass attenuation coefficients, respectively.

References in periodicals archive ?
To obtain the power attenuation rate, the attenuation constant of the composite electrical field, E = [square root of [E.
The attenuation rate of the crystal silicon modules will not exceed 2% within two years nor exceed 20% within 25 years.
The goal of the investigation was to determine an upper attenuation rate, and it's clear that none of the simulated source configurations falls off faster than 20 dB/decade up to about [R.
Recently demonstrated in the United States and United Kingdom, RIM IV not only achieves a greater distance of TX and RX separation, but the new system incorporates measurements of signal phase shift, in addition to existing attenuation rate.
This attenuation rate is in contrast to the 6 dB per octave of distance associated with free-space propagation.