Linearizer

In signal processing, linearizers are electronic circuits which improve the non-linear behaviour of amplifiers to increase efficiency and maximum output power.

This increases linear operating range up to the saturation (maximum output power) of the amplifier.

[1] Non-linearities occur in amplifiers due to decreasing amplification and changing phase when operated near saturation.

The point where the gain of the total system is starting to drop off is pushed to a higher power level thereby increasing the linear operating range.

In practice, the linear output power level of an amplifier increases significantly (up to four times).

The chart shows the relationship between input and output power of an amplifier with and without pre-distortion linearizer.

Pre-distortion linearizers operate in the small signal area and increase the DC power consumption of the system only marginally.

Fig. 1: Gain plotted against input power
Fig. 2: Output Power contingent upon input power