As a method to compensate for the nonlinear distortion of a power amplifier, the adaptive predistorter and the negative feed-back system are known. Although the feed-back method is a simple technique, its instability becomes a problem for a high feedback gain to achieve a high compensation effect. On the other hand, the predistorter needs long time to calculate the suitable parameters. In this paper, we propose a nonlinear distortion compensation method for a narrow-band signal. In this method, adaptive predistorter and negative feedback are combined. In addition, to shorten the convergence time to minimize non-linear distortion, a variable step-size (VS) method is also applied to the algorithm to find the parameters of adaptive predistorter. With computer simulations, we show that the proposed scheme achieves both five times faster convergence speed than that of the predistorter and three times higher permissible delay time in the feed-back amplifier than that of a negative feed-back only amplifier, even when the VS algorithm is employed in both the conventional and the proposed systems.
|Number of pages||6|
|Publication status||Published - Oct 30 2006|
|Event||GMC'2006: 2006 Global Mobile Congress - Beijing, China|
Duration: Oct 9 2006 → Oct 11 2006
|Other||GMC'2006: 2006 Global Mobile Congress|
|Period||10/9/06 → 10/11/06|
All Science Journal Classification (ASJC) codes