Power-added efficiency (PAE) is a metric for rating the
efficiency
Efficiency is the often measurable ability to avoid making mistakes or wasting materials, energy, efforts, money, and time while performing a task. In a more general sense, it is the ability to do things well, successfully, and without waste.
...
of a
power amplifier
An audio power amplifier (or power amp) amplifies low-power electronic audio signals, such as the signal from a radio receiver or an electric guitar pickup, to a level that is high enough for driving loudspeakers or headphones. Audio power a ...
that takes into account the effect of the gain of the
amplifier
An amplifier, electronic amplifier or (informally) amp is an electronic device that can increase the magnitude of a signal (a time-varying voltage or current). It is a two-port electronic circuit that uses electric power from a power su ...
. It is calculated (in percent) as:
It differs from most power efficiency descriptions calculated (in percent) as:
PAE will be very similar to
efficiency
Efficiency is the often measurable ability to avoid making mistakes or wasting materials, energy, efforts, money, and time while performing a task. In a more general sense, it is the ability to do things well, successfully, and without waste.
...
when the gain of the RF power amplifier is sufficiently high such that a low RF input power causes the RF power amplifier output to reach a certain level. But if the RF power amplifier gain is relatively low then the amount of RF input power that is needed to drive the RF power amplifier output to the certain level should be considered in a metric that measures the efficiency of the said power amplifier.
References
* http://www.maxim-ic.com/glossary/index.cfm/Ac/V/ID/1010/Tm/power-added-efficiency-PAE
* https://www.microwaves101.com/encyclopedias/efficiency-of-microwave-devices
Electronic amplifiers