摘要：Focusing on the linearity shortcoming on a bipolar low noise amplifier(LNA),a new 6 ~14GHz four stage SiGe HBT LNA is *** amplifier adopts a method of gain allocation on multiple stages to avoid the limitation on linearity especially with the addition of negative gain on the third *** realize gain flatness,extra zero is introduced to compensate the gain roll-off formed by pole,and local shunt-shunt negative feedback is used to widen the bandwidth as well as optimize circuit' s *** results have shown that in 6 ~14GHz,this circuit achieves noise figure(NF) less than 3dB,gain of 17.8dB(+0.2dB),input and output reflection parameters of less than- 10 dB,and the K factor is above 1.15.

摘要：针对单级宽带低噪声放大器(LNA)非线性难以定量分析及难以将电路与线性指标联合设计的问题,提出利用Volterra级数和双极非线性模型相结合的方法优化电路线性度。该方法从SiGe双极管非线性模型出发,提取影响线性度的模型参数,并利用维塔里级数和双极管非线性模型导出器件非线性传输函数,推演出其与IIP3的相互关系,量化各个参数的非线性比重,提出优化线性度的电路设计方法。研究结果表明,在1.5~20 GHz的宽频工作频带下,单级低噪声放大器的输入和输出均可实现良好的匹配(<-10 d B),达到16d B的增益,噪声系数在整个频带下小于3.6 d B,IIP3可达-7.73 d Bm。