Power efficiency (PAE) is a characteristic value of RF power amplifiers and transistors. It is particularly interesting for battery-powered mobile devices
, since an increase in the power efficiency can increase the battery-powered operating time. Power efficiency is the ratio of power
output to power input. Specifically, power efficiency (PAE) is the difference between the output and input power relative to the power input.The output power is the power that the amplifier delivers to the antenna or other load, the input power is the power that the amplifier receives from the upstream preamplifier
, and the supplied power is the power that is drawn from the supply voltage.
If, for example, the output RF power is 2.5 W, the input power supplied is 0.4 W, and the power required from the DC voltage source is 5 W, then this results in a PAE efficiency of 42 %.