High performance wideband digital predistortion platform for 3G+ applications with better than 55dBc over 40 MHz bandwidth

In this paper, a hardware-software system is proposed for the wideband characterization and linearization of power amplifiers exhibiting memory effects. The designed prototype includes a signal generation and a feedback paths for applications in the 1GHz to 2.5GHz frequency band and supports instantaneous bandwidths of up to 60MHz. The hardware platform is coupled with a software interface that implements the required data processing algorithms for the synthesis of the digital predistortion function. Experimental validation is carried out on a 3G power amplifier driven by an eight-carrier WCDMA signal. The digital predistortion is implemented using the twin-nonlinear two-box model with only 30 parameters and leads to a better than 55dBc ACLR for an input signal having 40MHz instantaneous bandwidth. To the best of the authors' knowledge this represents the best digital predistortion performances in terms of bandwidth and complexity.

[1]  W.H. Doherty,et al.  A New High Efficiency Power Amplifier for Modulated Waves , 1936, Proceedings of the Institute of Radio Engineers.

[2]  Hamid Jafarkhani,et al.  On the computation and reduction of the peak-to-average power ratio in multicarrier communications , 2000, IEEE Trans. Commun..

[3]  F. Raab,et al.  Power amplifiers and transmitters for RF and microwave , 2002 .

[4]  F.M. Ghannouchi,et al.  Twin Nonlinear Two-Box Models for Power Amplifiers and Transmitters Exhibiting Memory Effects With Application to Digital Predistortion , 2009, IEEE Microwave and Wireless Components Letters.

[5]  Holger Arthaber,et al.  RF Power Amplifier Design , 2001 .

[6]  Jangheon Kim,et al.  Analysis of a Fully Matched Saturated Doherty Amplifier With Excellent Efficiency , 2008, IEEE Transactions on Microwave Theory and Techniques.

[7]  F.M. Ghannouchi,et al.  Design Optimization and DPD Linearization of GaN-Based Unsymmetrical Doherty Power Amplifiers for 3G Multicarrier Applications , 2009, IEEE Transactions on Microwave Theory and Techniques.

[8]  Frederick Raab,et al.  Efficiency of Doherty RF Power-Amplifier Systems , 1987, IEEE Transactions on Broadcasting.

[9]  Slim Boumaiza,et al.  Complexity reduced odd-order memory polynomial pre-distorter for 400-watt multi-carrier Doherty amplifier linearization , 2008, 2008 IEEE MTT-S International Microwave Symposium Digest.

[10]  Jangheon Kim,et al.  A New Wideband Adaptive Digital Predistortion Technique Employing Feedback Linearization , 2008, IEEE Transactions on Microwave Theory and Techniques.