一种基于非均匀记忆多项式的数字预失真方法

A Digital Predistortion Method Based on Non-uniform Memory Polynomial

为了提高功率放大器线性化性能,提出了一种基于非均匀记忆多项式(Nonuniform Memory Polynomial, NMP)和线性插值查找表(Look-Up Table, LUT)结合的基带数字预失真方法。与传统的记忆多项式(Memory Polynomial, MP)模型相比,NMP模型具有更少的系数和较低的计算复杂度,同时能获得相近的建模精度。在NMP模型的基础上,采用线性插值LUT代替求解多项式的计算过程,进一步降低预失真处理的计算复杂度。对提出的数字预失真方法进行了仿真测试,仿真结果表明,相比基于传统MP模型的预失真方法,提出的方法能够获得相近的线性化性能,并在预失真处理消耗时间上有较大优势。

In order to improve the linearization performance of power amplifier,this paper presents an improved baseband digital predistortion method based on a Nonuniform Memory Polynomial(NMP)model and linearly interpolated Look-Up Tables(LUT).Compared with traditional Memory Polynomial(MP)models,the NMP model has less coefficients and lower computational complexity,but can obtain similar modeling accuracy.Based on the non-uniform memory polynomial model,linearly interpolated LUT is used to replace the calculation process of solving polynomial,for further reducing the computational complexity of predistortion processing.The proposed improved digital predistortion method is simulated.Simulation results show that the proposed method can achieve similar linearization performance and has less time consumption compared with the digital predistortion method based on traditional memory polynomial model.