一种新型的5GHz自适应偏置及可变增益低噪声放大器  

A New 5GHz Adaptively-Biased and Variable Gain Low Noise Amplifier

作　　者：徐化[1] 姚远[1] 石寅[1] Fa Foster Dai 

机构地区：[1]中国科学院半导体研究所神经网络与高速电路实验室,北京100083 [2]美国Auburn大学电机与计算机工程系

出　　处：《电子与信息学报》2006年第8期1521-1525,共5页Journal of Electronics & Information Technology

摘　　要：该文提出了一种新型的自适应偏置及可变增益低噪声放大器(LNA),利用电荷泵(亦称电压倍增器)将LNA输出信号转换成与LNA射频输入信号功率成比例变化的直流信号,以此信号同时反馈控制LNA的偏置和增益,来实现自适应偏置以及可变增益低噪声放大器,从而极大地改善了LNA的输入线性范围。鉴于5GHz频率下,Bipolar相对于CMOS更好的频率特性和低噪声特性,该项研究采用了BiCMOS工艺,实现了低于3.0dB的噪声系数(高增益状态下)和大约13dBm的输入三阶交调点IIP3的控制范围以及大于15dB的增益控制范围。In this paper, a new Low Noise Amplifier （LNA） with adaptive-biasing and variable gain is presented, in which charge pump is used to convert the RF output signal of LNA into a de control signal, the amplitude of which should be proportional to the input RF magnitude. By using this signal to control bias and gain of LNA simultaneously, the linearity of LNA is greatly improved. In 5GHz frequency, bipolar transistors exhibit better frequency and noise performance, so in this paper, BiCMOS technology is used. The LNA exhibits a noise figure of no more than 3.0dB （in the high gain mode）, about 13dBm ⅡP3 improvement and gain tuning range of more than 15dB.

关 键 词：低噪声放大器 自适应偏置 可变增益 电荷泵 

分 类 号：TN722.3[电子电信—电路与系统]