利用FFT估计正弦信号的频率,要估计一个叠加了高斯白噪声的正弦信号 的频率 ，可以通过对x(n)做傅里叶变换，得到频谱图，找出幅度的最大值对应的频率值 ，进行多次变换，求出均方误差 。改变信噪比SNR，通过仿真可以得出随着信噪比增加，均方误差减小。-Sinusoidal signal using FFT frequency estimation, to estimate a Gaussian white noise superimposed on the frequency of sinusoi

对正弦信号进行傅里叶变化，然后估计频率，在不同信噪比下画出均值方差的图-In the data process the measured complex time signal is converted into frequency signal by DFT to get vibration information regarding frequency and amplitude of the rotor

利用最小二乘法的原理高精度估计正弦波信号的幅值，频率和初相-The principle of using the least squares method estimated sine wave signal amplitude, frequency and initial phase of high-precision