Mixer gain calibration method and apparatus

摘要

A gain calibration circuit comprises a generator that generates a constant overdrive voltage that biases a radio frequency (RF) mixer. A reference signal generator generates a reference signal. A comparator receives the reference signal and a second signal that is a function of a mixer bias current flowing through the RF mixer and that generates a difference signal. An adjustment circuit adjusts a transconductance gain of the RF mixer based on the difference signal.