摘要
提出了一种改进型的Doherty功率放大器。根据输入功率的大小不同,Doherty功率放大器的主功率放大器漏极采用两个不同的电压来供电,进而来提高Doherty功率放大器的效率。实现方法是在输入为小功率时用低电平给Doherty功率放大器主放大器漏极供电;输入为大功率时用高电平给主功率放大器漏极供电。用开关来对Doherty功率放大器主放大器漏极电压进行切换。首先从输入端耦合一路信号,再经过检波器,比较器等处理,最后放大器把信号放大来驱动开关实现电压切换。用峰值包络功率(PEP)为10 W的MRF6S20010N LDMOSFET设计了频率为2 140 MHz的Doherty功率放大器,并且设计了漏极电压切换电路。通过对传统Doherty功率放大器和有电压进行调制的Doherty功率放大器的比较得出,小功率输入,连续波(CW)测试时得到改进的Doherty功率放大器的功率附加效率相比于传统的Doherty功率放大器提高了4%左右。
An improved Doherty power amplifier （DPA） was presented. According to the input power, the drain of main power amplifier of Doherty power amplifier was supplied by two different voltages to improve the overall efficiency of the DPA. The method was that the main amplifier of Doherty amplifier was powered by low drain voltage at low power region and high drain voltage at high power region. The main amplifier drain voltages were switched by a switch. Firstly, the switched signal was coupled from the input signal, then processed by a detector and a comparator etc. Finally, it was amplified by an amplifier to drive the switch. The 2 140 MHz Doherty power amplifier was implemented using 10 W PEP （peak envelope power） MRF6S20010N LDMOSFETs and a drain voltage switched circuit was designed. In low input power, the measured power added efficiency （PAE） of the improved DPA is about 4%, which is higher than the conventional DPA under continuous wave （CW） signal test.
出处
《半导体技术》
CAS
CSCD
北大核心
2013年第10期740-744,共5页
Semiconductor Technology
