In this paper two procedures are proposed for the estimation of the frequency, amplitude, and phase of sine-waves affected by either wideband noise or by both noise and harmonic distortion, respectively. The procedures are very simple and suitable for real-time applications. According to them, firstly the signal parameters are estimated by means of the new Corrected Interpolated Discrete Fourier transform (IpDFTc) algorithm, which compensates the contribution of the spectral interference from the fundamental image component and harmonics on the parameter estimates returned by the classical IpDFT algorithm. Then, a linear sine-fit algorithm is applied to optimize the noise robustness of the estimators, which is worsened by signal windowing employed to reduce the effect of spectral leakage on the IpDFTc estimates. In the paper, the Hann window is applied since it exhibit both the highest noise robustness among the Maximum Sidelobe Decay (MSD) windows and a good reduction of long-range spectral leakage. It has been shown that both proposed procedures almost attain the Cramér-Rao Lower Bounds (CRLBs) for unbiased estimators when at least about 1.5 sine-wave cycles are observed so that the effect of interfering tones on the IpDFTc estimates can be effectively compensated by windowing. The performances of both procedures are analysed through computer simulations and experimental results.

在本文中，提出了两种程序来分别估计受宽带噪声或噪声和谐波失真影响的正弦波的频率，幅度和相位。该过程非常简单，适合实时应用。根据它们，首先，通过新的校正内插离散傅里叶变换（IpDFTc）算法估计信号参数，该算法补偿了基本图像分量和谐波对经典IpDFT算法返回的参数估计值的频谱干扰的影响。 。然后，应用线性正弦拟合算法来优化估计器的噪声鲁棒性，而信号鲁棒性会降低信号泄漏，从而减少频谱泄漏对IpDFTc估计的影响，从而恶化了估计器的噪声鲁棒性。在纸上 之所以使用Hann窗口，是因为它在最大旁瓣衰减（MSD）窗口中显示出最高的噪声鲁棒性，并且可以很好地减少远程频谱泄漏。已经表明，当观察到至少约1.5个正弦波周期时，两种拟议的程序几乎都能获得无偏估计量的Cramér-Rao下界（CRLB），从而可以通过开窗有效地补偿干扰音对IpDFTc估计量的影响。通过计算机仿真和实验结果分析了这两种程序的性能。已经表明，当观察到至少约1.5个正弦波周期时，两种拟议的程序几乎都能获得无偏估计量的Cramér-Rao下界（CRLB），从而可以通过开窗有效地补偿干扰音对IpDFTc估计量的影响。通过计算机仿真和实验结果分析了这两种程序的性能。已经表明，当观察到至少约1.5个正弦波周期时，两种拟议的程序几乎都能获得无偏估计量的Cramér-Rao下界（CRLB），从而可以通过开窗有效地补偿干扰音对IpDFTc估计量的影响。通过计算机仿真和实验结果分析了这两种程序的性能。