On the Robustness of Digital Predistortion Function Synthesis and Average Power Tracking for Highly Nonlinear Power Amplifiers

@article{07-Hammi, abstract = {In this paper, a comprehensive study of the robustness of the digital predistortion function synthesis is presented. This study covers two aspects: the processing of the power amplifier (PA) input and output measured data intended for the extraction of the corresponding predistortion function, and the optimal setting of the predistorter's small-signal gain to adaptively track the average power variation between the input and output of the pre-distorter. First, the accuracy of the polynomial curve fitting and the lookup table's scheme in mimicking the measured AM/AM and AM/PM characteristics of the PA is investigated. To address the high dispersion of coefficients of the polynomial function, which limits the order that can be implemented and the fitting capabilities, a pre-processing technique is proposed. Second, the fitted PA curves are used to investigate the effects of the small-signal gain of the predistortion function on the linearization performance. An automated average power tracking technique is introduced in order to maintain a unit average gain of the predistorter. The measured spectra at the output of the amplifier show an additional 12-dBc improvement in the output spectrum regrowth.}, author = {Hammi, O. and Boumaiza, S. and Ghannouchi, F. M. }, booktitle = {Microwave Theory and Techniques, IEEE Transactions on}, citeulike-article-id = {2754938}, doi = {10.1109/TMTT.2007.895237}, journal = {Microwave Theory and Techniques, IEEE Transactions on}, keywords = {average, dpd, extraction, parameter, power, robustness, tracking}, number = {6}, pages = {1382--1389}, posted-at = {2008-05-05 03:58:47}, priority = {2}, title = {On the Robustness of Digital Predistortion Function Synthesis and Average Power Tracking for Highly Nonlinear Power Amplifiers}, url = {http://dx.doi.org/10.1109/TMTT.2007.895237}, volume = {55}, year = {2007} }

TY - JOUR ID - 07-Hammi L3 - citeulike-article-id:2754938 TI - On the Robustness of Digital Predistortion Function Synthesis and Average Power Tracking for Highly Nonlinear Power Amplifiers T2 - Microwave Theory and Techniques, IEEE Transactions on JF - Microwave Theory and Techniques, IEEE Transactions on VL - 55 IS - 6 SP - 1382 EP - 1389 N2 - In this paper, a comprehensive study of the robustness of the digital predistortion function synthesis is presented. This study covers two aspects: the processing of the power amplifier (PA) input and output measured data intended for the extraction of the corresponding predistortion function, and the optimal setting of the predistorter's small-signal gain to adaptively track the average power variation between the input and output of the pre-distorter. First, the accuracy of the polynomial curve fitting and the lookup table's scheme in mimicking the measured AM/AM and AM/PM characteristics of the PA is investigated. To address the high dispersion of coefficients of the polynomial function, which limits the order that can be implemented and the fitting capabilities, a pre-processing technique is proposed. Second, the fitted PA curves are used to investigate the effects of the small-signal gain of the predistortion function on the linearization performance. An automated average power tracking technique is introduced in order to maintain a unit average gain of the predistorter. The measured spectra at the output of the amplifier show an additional 12-dBc improvement in the output spectrum regrowth. KW - average KW - dpd KW - extraction KW - parameter KW - power KW - robustness KW - tracking AU - Hammi, O AU - Boumaiza, S AU - Ghannouchi, FM PY - 2007/// UR - http://dx.doi.org/10.1109/TMTT.2007.895237 ER -