FPGA Implementation of a Hammerstein Based Digital Predistorter for Linearizing RF Power Amplifiers with Memory Effects

Document Type : Research Article


1 PhD. Student, Department of Electrical Engineering, Amirkabir University of Technology, Tehran, Iran

2 MSc. Student, Department of Electrical Engineering, Amirkabir University of Technology, Tehran, Iran

3 Assistant Professor, Department of Electrical Engineering, Amirkabir University of Technology, Tehran, Iran


Power amplifiers (PAs) are inherently nonlinear elements and digital predistortion is a highly cost-effective approach to linearize them. Although most existing architectures assume that the PA has a memoryless nonlinearity, memory effects of the PAs in many applications ,such as wideband code-division multiple access (WCDMA) or orthogonal frequency-division multiplexing (OFDM), can no longer be ignored and memoryless predistortion has limited effectiveness.
In this paper, a novel digital predistorter based on the Hammerstein structure has been proposed for linearization of radio frequency power amplifiers with memory effect. Designing the Hammerstein model based digital predistorter has been done using an accurate Wiener model of the power amplifier. The proposed digital predistorter has many advantages such as low computational complexity, low memory space and simple implementation. The elimination of nonlinear effects and constructing accurate behavioral model, which is the exact inverse of a power amplifier characteristic, have been demonstrated by simulating 64 QAM constellation diagram in Matlab. In order to validate the proposed predistorter, it is implemented in Kintex FPGA using Vivado HLS and acceptable results have been obtained.


[1]S. Afsardoost, T. Eriksson, and C. Fager, “Digital predistortion using a vector-switched model,” IEEE Trans. Microw. Theory Tech., vol. 60, no. 4, pp. 1166–1174, Apr. 2012.
[2]Behzad Razavi, RF Microelectronics, 2nd Edition, September 2011.
Chowdhury D, Hull CD, Degani OB, Wang Y, Niknejad AM. “A fully integrated dual-mode highly linear 2.4 GHz CMOS power amplifier for 4G WiMAX applications:. IEEE J Solid-State Circuits 2009; 44 (December (12)): 3393–402.
Nazim Ceylan, inearization of power amplifiers by means of digital predistortion, Phd Dissertation, University of Nurnberg, Germany, 2005.
H. Qian, H. Huang, and S. Yao, “A general adaptive digital predistortion architecture for stand-alone RF power amplifiers,” IEEE Trans. Broadcasting, vol. 59, no. 3, pp. 528–538, Sep. 2013.
Rahul Gupta, Saad Ahmad, Reinhold Ludwig and John Mcneil, “Adaptive Digital Baseband Predistortion for RF Power Amplifier Linearization,” High Frequency Electronics, September 2006, pp. 16-25.
Chao Yu, Michel Allegue-Martínez, Yan Guo and Anding Zhu, “Output-Controllable Partial Inverse Digital Predistortion for RF Power Amplifiers,” IEEE Transactions on Microwave Theory and Techniques, Vol. 62, no. 11, November 2014.
J. Kimand K. Konstantinou, “Digital predistortion of wideband signals based on power amplifier model with memory,” Electron. Lett., vol. 37,no. 23, pp. 1417–1418, Nov. 2001.
T.Liu, S.Boumaiza,and F.M.Ghannouchi, “Augmented Hammerstein predistorter for linearization of broadband wireless transmitters,”IEEE Trans. Microw. Theory Techn., vol. 54, no. 4, pp. 1340–1349, Jun. 2006.
F. M. Ghannouchi and O. Hammi, “Behavioral modeling and predistortion,” IEEE Microw. Mag., vol. 10, no. 7, pp. 52–64, Dec. 2009.
L. Ding, G. T. Zhou, D. R.Morgan, Z.Ma, J. S. Kenney, J. Kim, and C. R. Giardina, “A robust digital baseband predistorter constructed using memory polynomials,” IEEE Trans. Communications, vol. 52, no. 1,pp. 159–165, Jan. 2004.
M. Younes and F. M. Ghannouchi, “An accurate predistorter based on feedforward Hammerstein structure,” IEEE Trans. Broadcast., vol. 58, no. 3, pp. 454–461, Sep. 2012.
L.Xu,X.Wu,M. Zhang,G.Kang, and P. Zhang, “A stable recursive algorithm for memory polynomial predistorter,” in Proc.MILCOM2007,Orlando, Florida, pp. 29-31, Oct.2007.
H. Jiang, X. Yu, and P. A. Wilford, “Digital
predistortion using stochastic conjugate gradient method,” IEEE Trans. Broadcast., vol. 58,no. 1, pp. 114–124, Mar. 2012.
R. Raich, H. Qian, and G. T. Zhou, “Orthogonal polynomials for power amplifier modeling and predistorter design,” IEEE Trans. Veh. Tech.,vol. 53, no. 5, pp. 1468–1479, Sep. 2004.
Gilabert Pinal, Multi look-up table digital predistortion for RF power amplifier linearization. Phd Dissertation, Control Monitoring and Communications Group Department of Signal Theory and Communications, Universitat Politecnica de Catalunya, 2007.
L. Ding and G. T. Zhou, “Effects of even-order nonlinear terms on power amplifiermodeling and predistortion linearization,” IEEE Trans.Veh. Te chl., vol. 53, no. 1, pp. 156–162, Jan. 2004.
J. C. Pedro and S. Maas, “A comparative overview of microwave and wireless power-amplifier behavioral modeling approaches,” IEEE Trans.Microw. Theory Tech., vol. 53, no. 4, pp. 1150–1163, Apr. 2005.
C. J. Clark, G. Chrisikos, M. S. Muha, A. A. Moulthrop, and C. P.Silva, “Time-domain envelope measurement technique with application to wideband power amplifier modeling,” IEEE Trans. MicrowaveTheory and Techniques, vol. 46, no. 12, pp. 2531–2540, Dec. 1998.
L. Guan, and A. Zhu, “Low-cost FPGA implementation of Volterra series-based digital predistorter for RF power amplifiers,” IEEE Trans. Microw. Theory Tech, vol. 58, no. 4, pp. 866 - 872, Apr. 2010.
A. A. M. Saleh, “Frequency-independent and frequency-dependent nonlinear models of TWT amplifiers,” IEEE Trans. Communications,vol. COM-29, no. 11, pp. 1715–1720, Nov. 1981.
I. Teikari, “Digital Predistortion Linearization Methods for RF Power Amplifiers” PHD Thesis, Helsinki University of Technology, 2008.
F. Taringou, O. Hammi, B. Srinivasan, R. Malhame, and F.M.Ghannouchi, “Behavior modeling of wideband RF transmitters using Hammerstein–Wiener models,” IET Circuits, Devices Syst., vol. 4, no. 4,pp. 282–290, Jul. 2010.
Xilinx, Vivado Design Suite User Guide: High-Level Synthesis (UG902 (v2015.2)), PDF File, Xilinx, San Jose, California, June 2015.