说明：  基于matlab，针对调幅AM、调频FM和调相PM信号，分析在不同的噪声环境，包括高斯白噪声、色噪声、非高斯噪声及正弦干扰中，各种信号的二阶循环谱。可根据需要改变程序中信号或噪声环境，分析结果。
(Based on matlab, AM for AM, FM FM and PM phase modulation signals, analysis of noise in different environments, including Gaussian white noise, colored noise, non-Gaussian noise and sinusoidal interference, the various second-order cyclic spectrum signals. May need to change the process in accordance with the signal or noise environment, the results of the analysis.)