Proceedings of the IEEK Conference (대한전자공학회:학술대회논문집)
- 2000.09a
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- Pages.553-556
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- 2000
On the Linearization of Volterra Nonlinear Systems using DWT and a Predistorter
DWT 및 전치 왜곡기를 이용한 볼테라 시스템 선형화
Abstract
This paper proposes an adaptive linearization method of Volterra nonlinear systems using DWT(Discrete Wavelet Transform)and an LMS-type predistorter. In particular, the proposed wavelet transform-domain lineatization method leads to diagonalization of the input vector auto-correlation matrix which yields improvement of the convergence rate of the corresponding transform-domain LMS algorithm. Furthermore, the adaptive Volterra predistorter followed by a corresponding weakly Volterra nonlinear system(here. a TWT amplifier model in a satellite communication system) is utilized to compensate for the distortion in the output. Also,12-PSK and 4-QAM are applied as the input to the nonlinear system to be tested. Some simulation results show that the proposed linearization approach has better performance than DCT-based or conventional normalized LMS algorithms do.
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