WCDMA直放站功率放大器预失真线性化技术研究  

Research of Predistortion Linearization Technique of Power Amplifier in WCDMA Repeater

作　　者：张翼[1] 

机构地区：[1]重庆邮电大学通信与信息工程学院,重庆400065

出　　处：《电光系统》2011年第2期19-22,共4页Electronic and Electro-optical Systems

摘　　要：在WCDMA直放站中，由于WCDMA系统使用了非恒定包络调制方式，所以对于其所使用的功率放大器线性度要求较高。在众多线性化手段中，预失真技术由于其结构简单、性能优良、成本低等特点成为较受欢迎的一种改善功放非线性的方法。但是传统的模拟预失真电路结构对预失真器所在支路产生的基频分量抑制并不彻底，在一定程度上削弱了基频信号。本文设计了一种可以较大程度抵消预失真器残存基频分量的预失真结构，可明显改善功放交调失真，并使得基频信号得到较为完整的保留。仿真结果显示，该结构有效改善了功放产生的交调失真，将三阶交调改善到45dB以上。The power amplifier in WCDMA repeater lope modulation. Compared with other linearization requires high lineartity due to the use of non-constant envetechniques, predistortion technique provides simple circuit design, good performance and relative low cost. But the restraint of the traditional analog predistortion circuit structure to the base freqnency component in the branch circuit incorporating the predistribution is not complete, thus weakening the base frequency signal to some extent. A new predistortion circuit is proposed to cancel out the remain base frequency component in the predistortion, thus significantly improving the intermodulation dostortion of the power amplification and rathe completely keeping the base frequency signal. Simulation results indicate that this circuit structure effectively improves the intermodulation in power amplification, obtaining an improvement to the three-order intermodutation to over 45 dB.

关 键 词：功率放大器 线性化 预失真 三阶交调 

分 类 号：TN722[电子电信—电路与系统]