Identification and Mitigation of Intermodulation Products Using a Baseband Polynomial Distortion Model with Instantaneous Frequency Dependence

Abstract

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.

ADC low-complexity modelling identification and mitigation of baseband intermodulation distortion with instantaneous frequency dependence

“…A measurement bench is then presented, allowing the calibration of our ADC, and finally results of identification and linearization by compensation are shown. This paper is an extended version of [21].…”