power level

https://doi.org/10.1351/goldbook.P04793
Logarithm of the ratio of a @[email protected] to a reference @[email protected] Levels are expressed in different ways: \(L_{P}=\frac{1}{2}\ \ln (\frac{P}{P_{0}})\ \mathrm{Np}\), where \(\mathrm{Np}\) is the symbol for the unit @[email protected] coherent with the SI, or \(L_{P}=10\ \log _{10}(\frac{P}{P_{0}})\ \mathrm{dB}\), where \(\mathrm{dB}\) is the symbol for the unit @[email protected]
Source:
Green Book, 2nd ed., p. 79 [Terms] [Book]