#LOGARITHMIC DECIBEL SCALE FULL#

5.2.5 Radio power, energy, and field strength.5.1 'Absolute' and 'relative' decibel measurements.5 Common reference levels and corresponding units.For a similar unit using natural logarithms to base e, see neper. The definitions of the decibel and bel use base-10 logarithms. The practice of attaching a suffix in this way, though not permitted by SI, is widely followed. For example, 'dBm' indicates that the reference quantity is one milliwatt, while 'dBu' is referenced to 0.775 volts. The decibel symbol is often qualified with a suffix, which indicates which reference quantity or frequency weighting function has been used.

#LOGARITHMIC DECIBEL SCALE FULL#

The full name decibel follows the usual English capitalization rules for a common noun. However, following the SI convention, the d is lowercase, as it represents the SI prefix deci-, and the B is capitalized, as it is an abbreviation of a name-derived unit (the bel). It confers a number of advantages, such as the ability to conveniently represent very large or small numbers, a logarithmic scaling that roughly corresponds to the human perception of, for example, sound and light, and the ability to carry out multiplication of ratios by simple addition and subtraction.

The decibel is useful for a wide variety of measurements in science and engineering (e.g., acoustics and electronics) and other disciplines. Since it expresses a ratio of two (same unit) quantities, it is a dimensionless unit. The decibel ( dB) is a logarithmic unit of measurement that expresses the magnitude of a physical quantity (usually power or intensity) relative to a specified or implied reference level. For other uses, see Decibel (disambiguation).

Logarithmic decibel scale