ROF与PA结合系统的数字预失真处理

Digital Predistortion for Radio-over-fiber Combined with Power Amplifier

摘要:

建立了一个光载无线通信（RoF）与功率放大器（PA）结合的无线通信系统的数字预失真仿真结构，使用Matlab软件建立RoF和PA的模型，并运用间接学习结构的预失真方法和最小均方误差（LMS）算法搭建了预失真仿真系统，采用联合补偿和单独补偿两种方式的补偿结构，分析了两种结构的优缺点。通过功率谱密度图的对比，分析了两种补偿方式的效果。仿真结果表明，预失真处理有效地补偿了RoF与PA组成的无线通信系统的非线性。

Abstract:

A simulation structure for digital predistortion of wireless communications system combining radio-over-fiber（RoF） with power amplifier(PA) was designed, the preditortion system and the modes of RoF and PA were established by Matlab software. Two architectures of joint compensation and separated compensation were used, and their advantages and disadvantages were analyzed. Applying the indirect learning architecture predistortion method with minimum mean square error (LMS) algorithm, the effects of the two compensation architectures were analyzed from comparisons of power spectral density charts. The simulation results show that the nonlinearity of communications system combining RoF with power amplifier is compensated effectively.