The linearization of active electronic components such as the PA or the ADC, is a vast subject. Many issues come into play, including behavioral modeling with the selection of a relevant model in terms of accuracy and complexity, the identification of this model, and the correction of defects by compensation. In this article, we propose a baseband model of nonlinearity defects observed at the digitization output and after IQ demodulation, with a focus on order 3 intermodulation. We then introduce a refinement of this model by adding a dependence on the variation of the instantaneous frequency of the signal. We describe a method suitable for calibration of the model, by identification on a two-tone signal. We finally present a measurement bench adapted to the calibration of the coefficients of the model, followed by some results of linearization.