Apple Inc.
Method and Apparatus for IIP2 Calibration

Abstract:

Aspects include an apparatus and a method for performing Second Order Input Intercept Point (IIP2) calibration of a Digital-to-Analog (DAC) during a full-duplex mode receive operation. In some aspects, a plurality of correlation values are obtained, indicating an amount of IMD energy of an RF signal, wherein the correlation values are associated with IIP2DAC values of a DAC. In some aspects, the apparatus can calculate a mixer bias value, based on the correlation values, and adjust a bias value of a mixer according to the determined bias value. The apparatus can obtain the correlation values, calculate the bias value, and adjust the bias value of the mixer during the full-duplex mode receive operation. In some aspects, the apparatus can thus improve IIP2 of the mixer and reduce IMD energy in a receive signal, during the receive operation, without the need of standby or factory calibration.