Abstract:

With the output power level becoming higher, especially the wider application of the technique of Dorherty radio frequency power amplifier (PA), the nonlinear characteristics of PA are stronger. In order to meet the high linearization requirements, digital predistortion (DPD) needs to achieve better performance in nonlinear correction. An approach of the DPD based on linear interpolation basis function is proposed, which introduces the linear interpolation basis function in DPD behavioral modeling to optimize the performance of the nonlinear correction. Meanwhile, combining with the lookuptable implementation, it is suitable for system applications. The 20 MHz long term evolution (LTE) signal is employed to do simulations. Results show that the proposed approach is almost 7 dBc better than the generalized memory polynomial approach in the adjacent channel leakage ratio.