双口网络噪声模型的系统理论及其应用

从放大器实际存在的时域原始噪声模型出发，推导出两个时域等效噪声模型，并由此扩展到频域，得到了相对应的几个功率谱噪声模型，从而系统地给出了双口网络噪声模型理论和一系列实用的计算公式．将这些理论应用到光纤通信接收机前置放大器的噪声计算上，用统一的方法，算出了光接收机ＢＪＴ和ＦＥＴ前置放大器的等效输入端噪声电压电流功率谱，供光接收机设计使用

SYSTEMATIC THEORY OF TWO PORT NETWORK NOISE MODEL AND ITS APPLICATION

The original noise model of a two port network is given. This model consists of a noise current source I n1 (t) at the input and another, I n2 (t) ,at the output.The sources I n1 ( t )and I n2 ( t )are directly related to the mechanism of the noise.From this model,two equivalent noise models in the time domain, V ni ( t ) model and V n( t) I n (t ) model, are derived.The noise model has to spread from the time domain to the frequency domain in order to measurable,therefore tree equivalent power spectrum noise models are obtained.Finelly,the equivalent input noise voltage current spectral density for both BJT and FET preamplifier in the fiber optical receivers are calculated by using the unified approach mentioned in this paper.