摘要
逆F类功放在接近饱和区工作时效率很高,将其与Doherty功放结构相结合,可以实现一种在大功率回退的情况下仍然具有很高效率的射频功率放大器。本文设计了一款基于Ga N HEMT晶体管的高效率的逆F类Doherty功率放大器,工作频带为910MHz^950MHz。单音信号测试结果显示,在930MHz处,功放回退7.5d B后漏极效率仍高达64.2%。使用3载波WCDMA信号作为测试信号,利用数字预失真技术进行线性化后,功放输出信号的上下边带邻信道功率比(ACPR)分别为-35.39d Bc和-35.9d Bc。
Inverse class-F power amplifier( IFPA) can obtain high efficiency when working close to the saturated state. By combining the IFPA with Doherty structure,a RF power amplifier characterized with high efficiency at huge power back-off region can be achieved. This paper presents the design and implementation of an inverse class F Doherty power amplifier using a Ga N HEMT transistor,which is designed at the band of 910MHz-950 MHz. From the measured results for a930 MHz single tone,the drain efficiency of 64. 2% is achieved at a 7. 5 d B back-off point from its saturated output power.Taking three-carrier WCDMA signal as a test signal,the proposed power amplifier is linearized by using the DPD techniques.After linearization,the measured adjacent channel power ratio( ACPR) is- 35. 9d Bc( lower) and- 35. 39 d Bc( upper).
出处
《微波学报》
CSCD
北大核心
2014年第6期64-68,共5页
Journal of Microwaves
基金
国家自然科学基金(61171040)
浙江省自然科学基金(Y1101270)
宁波大学学科项目(XKL141038)
