A frequency estimator of sinusoid by interpolated Discrete Fourier Transform (DFT) method based on maximum sidelobe decay (MSD) windows is proposed. Unlike other frequency estimators which use spectral lines located in fixed positions, the proposed estimator utilizes the maximum spectral line and two auxiliary spectral lines arbitrarily located within the weighted sinusoid spectrum main lobe. An accurate formula for the estimator MSE due to additive white noise is derived. To further improve the estimation performance, iterative procedure is used. It is analytically and numerically shown that the MSE increases with the increment of the interval length between the maximum spectral line and the auxiliary spectral line in additive white noise. The proposed estimator is more general and performs better than the competing estimators.

提出了一种基于最大旁瓣衰减（MSD）窗的内插离散傅里叶变换（DFT）方法对正弦波进行频率估计的方法。与其他使用位于固定位置的频谱线的频率估计器不同，所提出的估计器利用最大频谱线和任意位于加权正弦频谱主波瓣内的两条辅助频谱线。推导了由于加性白噪声而导致的估算器MSE的精确公式。为了进一步提高估计性能，使用了迭代过程。分析和数值显示，在加性白噪声中，MSE随着最大光谱线和辅助光谱线之间的间隔长度的增加而增加。拟议的估算器比一般的估算器更具通用性，并且表现更好。