Compression point

The compression point is a metric describing an aspect of electronic amplifiers.

For example, the 1-dB compression point (sometimes notated as P1dB[1][2]) is the output power of the amplifier (for the signal of interest) at which it differs from an ideal linear amplifier by more than 1 dB.

So a larger 1-dB compression point means that the amplifier can produce larger outputs (for the same amount of distortion).

[3] It will often be quoted by manufacturers of amplifiers[4]..[5] The compression point is sometimes used (interchangeably with the third-order intercept point) to define the upper limit of the dynamic range of an amplifier.

A rule of thumb that holds for many linear radio-frequency amplifiers is that the 1 dB compression point point falls approximately 10 dB below the third-order intercept point.