An adaptive digital predistorter with iterative noise cancelation

In this paper, we propose a linearization technique combined with an iterative noise cancelation. This method alleviate the effect of added noises which prevent a predistorter (PD) from estimating the exact characteristics of power amplifier (PA). To iteratively cancel the noise included in the feedback signal, the output signal of power amplifier without noise is reconstructed by applying the inverse characteristic of PD to the predistorted signals, then the noise can be revealed by subtracting the reconstructed signals from the feedback signals. Simulation results based on the mean-square error (MSE) and power spectral density (PSD) criteria to evaluate PD performance is presented. The results show that the iterative noise cancelation method significantly enhances the MSE performance, which leads to an improvement of the out-of-band power suppression.

[1]  James K. Cavers.  A linearizing predistorter with fast adaptation , 1990, 40th IEEE Conference on Vehicular Technology.

[2]  Tho Le-Ngoc,et al.  A fast adaptive polynomial predistorter for power amplifiers , 2001, GLOBECOM'01. IEEE Global Telecommunications Conference (Cat. No.01CH37270).

[3]  한재희,et al.  전력증폭기의 실시간 복소 전달함수 추정을 이용한 적응 사전왜곡기의 설계 및 제작 ( Adaptive Predistorter for Power Amplifier based on Real-Time Estimation of Envelope Transfer Characteristics ) , 2001 .

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

[5]  G. Baudoin,et al.  Applying Digital Predistortion To Power Amplifiers Used in Third Generation Systems , 2002 .

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

[7]  Michael Faulkner,et al.  Adaptive linearization using predistortion-experimental results , 1994 .

[8]  Mohamad Sawan,et al.  Adaptive digital predistorter for power amplifiers with real time modeling of memoryless complex gains , 1996, 1996 IEEE MTT-S International Microwave Symposium Digest.

[9]  J. Cavers,et al.  An adaptive direct conversion transmitter , 1992, [1992 Proceedings] Vehicular Technology Society 42nd VTS Conference - Frontiers of Technology.

[10]  Young-Woo Seo,et al.  On the condition of adaptive digital predistorter with real-time update , 2009, 2009 9th International Symposium on Communications and Information Technology.