低噪声前置放大器的优化设计及电路实现

The Optimal Design and Circuit Execution for Low Noise Preamplifiers

目前,常用的低噪声设计方法是选择低噪声晶体管及合适工作点,使器件的噪声电阻等于信号源内阻。本文证明了这种方法不能给出最佳的低噪声性能,并提出正交优化方法及噪声匹配原理,使前置放大器真正工作在最低噪声状态。文中还给出了低噪声设计实例和一些实验结果,说明我们提出的这种方法是有效的。

Today, the usual low noise design is to chose transistor and its quiescent point in order to ensure that the noise resistance equals the signal source resistance. In this paper, We demonstrate that this method can not give optimal low noise performance, and the low noise design is improved by means of noise matching principle and orthogonal optimal design method. The low noise design example and experiment results are given, which demonstrate that this method is perfact and effective.