Receiver IIP2 analog calibration

摘要

Techniques for performing analog calibration of a receiver to optimize a second-order input intercept point (IIP2). In an aspect, a signal generator modeling an interferer is coupled to an adjustable input of a receiver, e.g., a gate bias voltage of a mixer. For example, the signal generator output may be a single-tone on-off keying (OOK) modulated signal. The mixer mixes the signal down to baseband, wherein an analog correlator correlates the down-converted signal with the known sequence of bits used to perform the OOK modulation. The analog correlation output is then provided to drive the bias voltage in the mixer, e.g., one or more gate voltages of transistors in the differential mixer, to optimize the overall receiver IIP2. Further aspects of the disclosure provide for calibrating receivers having multiple LNA's, and also dual or diversity receivers having multiple receive paths.

主权项

1. An apparatus comprising:
a signal generator configured to generate a modulated input signal comprising modulation data; a receiver comprising a mixer configured to mix a signal derived from the modulated input signal with a local oscillator signal to generate a mixer output; an analog multiplier configured to multiply an input signal with the modulation data; and an analog integrator configured to integrate the output of the analog multiplier to generate an analog correlator output signal; wherein an adjustable input of the receiver is coupled to the analog correlator output signal.