Power-added efficiency (PAE) is a measure of the power conversion efficiency of the power amplifier. It shows how much of the DC power is converted to RF power in the power amplifier. PAE measurement is used to evaluate the improvements of power efficiency and output signal performance after using envelope tracking. For a PA, envelope tracking and digital predistortion can be used together. In this example, only envelope tracking is applied to the PA under test.
The whole measurement process includes the following three parts.