功放预失真中自适应算法研究

摘要

Digital pre⁃distortion is one of the most efficient ways to compensate power amplifier’s nonlinearity.And the choice of adaptive algorithm influences the system pre⁃distortion performance to some extent. LMS and RLS are frequently⁃used adaptive conver⁃gence algorithms.On the base of analyzing the advantage and disadvantage of the two methods,this paper presents a new algorithm, which combines LMS and RLS. Simulation results demonstrate that the new algorithm promotes system pre⁃distortion performance and lowers the system computational complexity.%数字基带预失真技术是补偿功放非线性的最有效方法之一，而自适应算法的选择很大程度上影响着系统的预失真性能。其中，最小均方误差（ LMS ）算法和递归最小二乘法（ RLS ）是最常用的自适应收敛算法， LMS 算法计算复杂度较低，但LMS算法收敛速度慢，易陷入局部最优且精度不高， RLS收敛性能较好，但计算复杂度高。在综合分析2种算法优缺点的基础上，提出了一种LMS和RLS算法的组合算法，仿真结果表明，组合算法的预失真性能很好，而且算法复杂度较低。