摘要
采用线性调制技术和多载波配置的通信系统对射频功率放大器的线性提出了很高的要求,前馈技术是一种很有前途的用于提高功率放大器线性的技术。对前馈功放的工作原理进行了介绍,分析了环路中幅度、相位及延迟等环路参数对抵消性能及带宽的影响。基于这些分析的结果,设计了一个10 W的WCDMA前馈功放,三阶互调性能改善了20 dB以上。
A linear power amplifier is particularly emphasized on the system that uses linear modulation method and multicarrier configuration. The feedforward technique is a promising approach to improving the linearity of power amplifiers. The principle of operation of the feedforward power amplifiers is illustrated. Then parameters of a linearization loop, such as an amplitude imbalance, a phase imbalance and a delay mismatch, are fully analyzed to get a specific cancellation performance and linearization bandwidth. Based on the analytical results, a 10-Watt feedforward power amplifier for WCDMA applications is implemented. The third-order intermodulation （IM3） cancellation performance is improved by more than 20 dB.
出处
《重庆邮电学院学报（自然科学版）》
2006年第1期22-25,共4页
Journal of Chongqing University of Posts and Telecommunications(Natural Sciences Edition)
关键词
射频功率放大器
前馈
互调失真
RF power amplifier
feedforward
intermodulation
