Electronic device with a distortion correction circuit for a power amplifier, and associated methods

A distortion correction circuit to be coupled between a signal source and a power amplifier of a radio frequency (RF) transmitter, the distortion correction circuit comprising:

• a variable gain amplifier to be coupled between the signal source and the power amplifier;
• and
• an amplitude correction control loop comprising
• a first logarithmic converter having an input to be coupled to the signal source,
• a second logarithmic converter having an input to be coupled to an output of the power amplifier, and
• a difference circuit coupled to outputs of said first and second logarithmic converters for controlling the gain of said variable gain amplifier for correcting distortion in an output signal from the power amplifier.

A method for correcting distortion in an output signal from a power amplifier of a radio frequency (RF) transmitter using a distortion correction circuit, the distortion correction circuit comprising a variable gain amplifier coupled between a signal source and the power amplifier, and an amplitude correction control loop comprising a first logarithmic converter having an input coupled to the signal source, a second logarithmic converter having an input coupled to an output of the power amplifier and a difference circuit coupled to outputs of the first and second logarithmic converters, the method comprising:

• using the first logarithmic converter for converting a signal from the signal source to a first logarithmic signal;
• using the second logarithmic converter for converting the output signal from the power amplifier to a second logarithmic signal;
• and
• using the difference circuit for determining a difference between the first and second logarithmic signals for controlling the gain of the variable gain amplifier for correcting the distortion in the output signal from the power amplifier.