多级放大器噪声谱矩阵计算及在低噪声设计中应用

The Calculation of Noise Matrix of a Multistage Amplifierand Its Application in Low Noise Electronics Design

本文针对通信接收机噪声性能分析中广泛采用的弗里斯（Ｆｒｉｓ）公式在低噪声设计中的不足，提出了具有复相关系数的放大器Ｅｎ－Ｉｎ噪声模型的谱矩阵形式，推导了多级放大器的噪声谱矩阵计算公式。成功地解决了多级放大器噪声性能分析及低噪声设计必需的噪声参数（最佳源阻抗及最小噪声系数）计算。

In this paper, the defects of the Friils's formula which is used in communication system has been shown. The noise matrix of an En-In noise model with complex correlation coefficient is introduced, then the calculation formula of noise matrix of a multistage amplifier has been given. This formula can be used to execute noise performance analysis of a multistage amplifier and to extract noise parameters of low noise electronics design (optimal source impedance and minimum noise figure).