Flicker noise elimination in a double balanced mixer DC bias circuit

A wireless device comprising:

• an antenna configured to emit a transmission signal;
• and
• a transmitter in communication with the antenna, the transmitter comprising:
• a mixer;
• a transconductance stage connected to the mixer;
• and
• a bias circuit connected to the transconductance stage, the bias circuit comprising:
• a programmable current source configured to provide a reference current;
• a replica circuit connected between the programmable current source and the transconductance stage, the replica circuit configured to replicate a DC signal of the transconductance stage;
• and
• a bias transistor connected to the replica circuit and the transconductance stage, the bias transistor configured to level shift a bias signal obtained from a signal source based on the reference current and the DC signal of the transconductance stage.

A method of biasing in a transmitter, the method comprising:

• generating a reference current using a programmable current source;
• replicating a DC signal of a transconductance stage using a replica circuit connected between the programmable current source and the transconductance stage, the transconductance stage connected to a mixer;
• obtaining a bias signal from a signal source;
• and
• level shifting the bias signal based on the reference current and the DC signal using a bias transistor connected to the replica circuit and the transconductance stage.