A new predistorter design for nonlinear power amplifiers using the minimum distortion power polynomial model (MDP-PM)

A new polynomial model for nonlinear power amplifiers (PA) was proposed by Lai and Bar-Ness (see IEEE Vehicular Technol. Conf., Amsterdam, the Netherlands, Sept. 1999) in their earlier work which takes into account both the input modulation format and the operating point of a PA. Such a model has been applied to analog predistorter (PD) design using a zero forcing scheme. In this paper, this model is applied to PD designs using the approach of approximating the ideal predistorter of the PA of interest. Based on the metric of the total degradation of a digital radio link with 64-QAM, the proposed PD has comparable performance of another PD obtained by the ideal approximation approach of D´Andrea, Lottici and Reggiannini (1996), but has less complexity in its implementation than the other one. In addition, based on the same metric, significant improvement is shown of the new PD over several PD designs using the zero forcing scheme, including the one proposed by Lai et al. However, the MDP-PM of the ideal PD has the same level of complexity as the PDs compared in the same order