说明：  噪声中正弦信号的现代法频谱分析，分析了自相关法、Burg法、协方差法和改进的协方差法对功率谱的影响以及阶数、信噪比、窗长度对自相关法频谱分析的影响。
(The influence of autocorrelation method, Burg method, covariance method and improved covariance method on power spectrum and the influence of order, signal-to-noise ratio and window length on the spectrum analysis of sinusoidal signal in noise are analyzed.)