An algorithm for precisely estimating loop-delay in digital predistortion system

In digital predistortion (DPD) design, loop-delay estimation for synchronization is an important work. In this paper, an algorithm for precisely estimating loop-delay in DPD system is proposed. The whole algorithm consists of integer loop-delay estimation and fractional loop-delay estimation. Amplitude-difference correlation function is used to estimate the integer loop-delay estimation. The fractional loop-delay estimation gets the estimate through recursive least squares (RLS) algorithm based on interpolation filter structure. Finally, a series of simulations prove the validity of the algorithm and the effect on the DPD system.

[1]  Kok Lay Teo,et al.  Optimum Design of Discrete-Time Differentiators via Semi-Infinite Programming Approach , 2008, IEEE Transactions on Instrumentation and Measurement.

[2]  Adel A. M. Saleh,et al.  Frequency-Independent and Frequency-Dependent Nonlinear Models of TWT Amplifiers , 1981, IEEE Trans. Commun..

[3]  Floyd M. Gardner,et al.  Interpolation in digital modems. I. Fundamentals , 1993, IEEE Trans. Commun..

[4]  Mao-Ching Chiu,et al.  Predistorter Based on Frequency Domain Estimation for Compensation of Nonlinear Distortion in OFDM Systems , 2008, IEEE Transactions on Vehicular Technology.

[5]  Hugo Durney,et al.  Coarse time delay estimation for pre-correction of high power amplifiers in OFDM communications , 2002, Proceedings IEEE 56th Vehicular Technology Conference.

[6]  Dae Hyun Kwon,et al.  A Fast Digital Predistortion Algorithm for Radio-Frequency Power Amplifier Linearization With Loop Delay Compensation , 2009, IEEE Journal of Selected Topics in Signal Processing.

[7]  Lars Erup,et al.  Interpolation in digital modems. II. Implementation and performance , 1993, IEEE Trans. Commun..

[8]  Jonmei J. Yan,et al.  Open-Loop Digital Predistorter for RF Power Amplifiers Using Dynamic Deviation Reduction-Based Volterra Series , 2008, IEEE Transactions on Microwave Theory and Techniques.

[9]  Zhixing Yang,et al.  Loop Delay Correction for Adaptive Digital Linearization of Power Amplifiers , 2007, 2007 IEEE Wireless Communications and Networking Conference.

[10]  G. Montoro,et al.  A New Digital Predictive Predistorter for Behavioral Power Amplifier Linearization , 2007, IEEE Microwave and Wireless Components Letters.

[11]  Yannis Papananos,et al.  A new non-iterative, adaptive baseband predistortion method for high power rf amplifiers , 2003, Proceedings of the 2003 International Symposium on Circuits and Systems, 2003. ISCAS '03..

[12]  Y. Nagata,et al.  Linear amplification technique for digital mobile communications , 1989, IEEE 39th Vehicular Technology Conference.