生成一个正弦信号，使用levinson-durbin算法和最终预测阶数准则FPE估计其AR模型的阶数，并且通过解Yule-Walker方程求得AR模型的参数，进而求得该正弦信号的功率谱-Generating a sinusoidal signal, using levinson-durbin algorithm to predict the order and final order of the criteria FPE estimates its AR model and AR model parameters obtained by solving the Yule-Walker equations, and then obtain the power spectrum of the sinusoidal signal