Linearization of differential RF power amplifier by bias control using cross-coupling components

A multi-stage amplifier comprising:

• two or more amplifier stages, wherein at least one of the two or more amplifier stages comprises:
• a first input terminal configured to receive a first input signal;
• a second input terminal configured to receive a second input signal;
• a differential amplifier providing differential amplification of the first and second input signals, wherein the differential amplifier comprises:
• a first differential amplifier stage including one or more transistors and configured to receive the first input signal;
• and
• a second differential amplifier stage including one or more transistors and configured to receive the second input signal;
• a first bias circuit including a first buffer to bias the first differential amplifier stage, wherein the first bias circuit is connected to the second input terminal to provide anti-phase bias control of the first differential amplifier stage;
• and
• a second bias circuit including a second buffer to bias the second differential amplifier stage, wherein the second bias circuit is connected to the first input terminal to provide anti-phase bias control of the second differential amplifier stage.

A communications device comprising:

• a transmitter to generate an input transmission signal;
• one or more amplifiers configured to receive the input transmission signal, wherein at least one of the one or more amplifiers comprises:
• an input transformer to receive the input transmission signal and generate a first input signal and a second input signal;
• a first input terminal configured to receive the first input signal;
• a second input terminal configured to receive the second input signal;
• a differential amplifier providing differential amplification of the first and second input signals, wherein the differential amplifier comprises:
• a first differential amplifier stage including one or more transistors and configured to receive the first input signal;
• and
• a second differential amplifier stage including one or more transistors and configured to receive the second input signal;
• a first bias circuit including a first buffer to bias the first differential amplifier stage, wherein the first bias circuit is connected to the second input terminal to provide anti-phase bias control of the first differential amplifier stage;
• and
• a second bias circuit including a second buffer to bias the second differential amplifier stage, wherein the second bias circuit is connected to the first input terminal to provide anti-phase bias control of the second differential amplifier stage, wherein the first and second differential amplifier stages provide first and second amplified output signals;
• an output transformer configured to receive the first and second amplified output signals and generate an amplified transmission signal;
• and
• an antenna configured to broadcast the amplified transmission signal.