Ratio between two power quantities expressed in decibels
The decibel is a logarithmic unit used to express the ratio between two values of a physical quantity. The bel represents a ratio between two power quantities of 10:1, and a ratio between two field quantities of √10:1.
A power quantity is a power or a quantity directly proportional to power. (One decibel is one tenth of one bel).The base-10 logarithm of the ratio of the two power levels is the number of bels.
|The ratio (in dB) of a power value to another power value (dimensionless)
|Power of one quantity (same units with Po) (dimensionless)
|Power of the other quantity (same units with P1) (dimensionless)