Modeling of wideband radio frequency power amplifiers using Zernike polynomials

In this article, we suggest a new set of basis functions that are based on Zernike polynomials for the behavioral modeling of radio frequency power amplifiers (PAs). The modeling of highly nonlinear PAs exhibits numerical instability that degrades the accuracy of the model parameters and predistorter modeling efficiency. Simulation results show that the proposed polynomial model is more suitable to resolve the numerical instability problem and proves to have greater accuracy with reduced complexity. A Doherty PA driven by a multicarrier wideband code division multiple access signal was used for validation; and, the obtained results show that the new model exhibits superior numerical stability as the nonlinearity order and memory depth of the model increase. © 2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2012. © 2012 Wiley Periodicals, Inc.

[1]  James K. Cavers,et al.  Simulation and analysis of an adaptive predistorter utilizing a complex spectral convolution , 1992 .

[2]  Magnus Isaksson,et al.  Digital predistortion of radio frequency power amplifiers using Kautz-Volterra model , 2006 .

[3]  M. Schetzen.  The Volterra and Wiener Theories of Nonlinear Systems , 1980 .

[4]  F.M. Ghannouchi,et al.  Power Amplifiers' Model Assessment and Memory Effects Intensity Quantification Using Memoryless Post-Compensation Technique , 2008, IEEE Transactions on Microwave Theory and Techniques.

[5]  J. M. Miller,et al.  Representation of videokeratoscopic height data with Zernike polynomials. , 1995, Journal of the Optical Society of America. A, Optics, image science, and vision.

[6]  J. Stevenson Kenney,et al.  Predicting spectral regrowth of nonlinear power amplifiers , 2002, IEEE Trans. Commun..

[7]  Dennis R. Morgan,et al.  A robust digital baseband predistorter constructed using memory polynomials , 2004, IEEE Transactions on Communications.

[8]  Michael B. Steer,et al.  Characterization of spectral regrowth in microwave amplifiers based on the nonlinear transformation of a complex Gaussian process , 1999 .

[9]  A. Zhu,et al.  Dynamic Deviation Reduction-Based Volterra Behavioral Modeling of RF Power Amplifiers , 2006, IEEE Transactions on Microwave Theory and Techniques.

[10]  Mark R. Morelande,et al.  Modeling of corneal surfaces with radial polynomials , 2002, IEEE Transactions on Biomedical Engineering.

[11]  Shawn Patrick Stapleton,et al.  An adaptive predistorter for a power amplifier based on adjacent channel emissions (mobile communications) , 1992 .

[12]  J.S. Kenney,et al.  Spline-Based Model for Digital Predistortion of Wide-Band Signals for High Power Amplifier Linearization , 2007, 2007 IEEE/MTT-S International Microwave Symposium.

[13]  Mark R. Morelande,et al.  A refined bootstrap method for estimating the Zernike polynomial model order for corneal surfaces , 2004, IEEE Transactions on Biomedical Engineering.

[14]  Raviv Raich,et al.  On the modeling of memory nonlinear effects of power amplifiers for communication applications , 2002, Proceedings of 2002 IEEE 10th Digital Signal Processing Workshop, 2002 and the 2nd Signal Processing Education Workshop..

[15]  M. Isaksson,et al.  A comparative analysis of behavioral models for RF power amplifiers , 2006, IEEE Transactions on Microwave Theory and Techniques.

[16]  Miroslaw Pawlak,et al.  On the Accuracy of Zernike Moments for Image Analysis , 1998, IEEE Trans. Pattern Anal. Mach. Intell..

[17]  N.B. Carvalho,et al.  A Formal Procedure for Microwave Power Amplifier Behavioral Modeling , 2006, 2006 IEEE MTT-S International Microwave Symposium Digest.

[18]  Timo Rahkonen,et al.  Measurement technique for characterizing memory effects in RF power amplifiers , 2001 .

[19]  N.B. Carvalho,et al.  A new Volterra series based orthogonal behavioral model for power amplifiers , 2005, 2005 Asia-Pacific Microwave Conference Proceedings.