射频接收机系统级建模中的噪声谱分析

Noise density research in the system-modeling of RF receivers

提出了一种在有限的系统参数下进行射频接收机系统建模时,各子电路噪声参数的分析和计算方法.从噪声功率谱的等效计算出发,给出了加性高斯白噪声通过有噪线性电路的分析方法.以一通信电台为例进行了分析计算,在给定有限的系统参数(信噪比,灵敏度,增益等)下分析出合理的各子电路的噪声参数,并进行建模仿真验证,理论结果与仿真结果较好吻合,表明了分析方法的有效性.该噪声功率谱的等效分析计算方法对射频系统建模有很好的指导作用.

A new method of noise analysis in RF （radio frequency） receivers is provided when the system modeling is required while only some limited parameters of the whole RF system are known. The analysis procedure of AWGN（additive white Gaussian noise） through noisy linear circuits is given in detail using the theory of equivalent computation of noise power density. Take a communication station as an example for noise computation and system modeling. Noise parameters of each component such as noise figure in the RF receiver are derived in the condition of limited system parameters of the receiver including SNR （signal noise ratio）, sensitivity, RF gain etc. Modeling and simulation are carried out to validate the analysis method and fair agreement between the theoretical and simulated results is obtained. This equivalent computation method of noise power density has a good instructional meaning to noise analysis and proper system modeling of RF receivers.