An accurate frequency estimator for real sinusoid based on Discrete Fourier Transform (DFT) is proposed. The proposed estimator is based on the interpolation of the maximum DFT spectral line and two Discrete-Time Fourier Transform (DTFT) spectral lines and can operate with both the rectangular window and the maximum sidelobe decay (MSD) window. In the coarse estimation step, the proposed estimator with the MSD window is used. According to the value of the coarse estimate, the negative frequency spectral component is removed. In the fine estimation step, the proposed estimator with the rectangular window is utilized to achieve the Cramer–Rao lower bound (CRLB). Simulation results show that the performance of this algorithm is better than that of the AM algorithm, Candan algorithm, Djukanovic algorithm, and FDIAM algorithm.

中文翻译：

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基于DFT的实正弦准确频率估计器

提出了一种基于离散傅里叶变换(DFT)的真实正弦波准确频率估计器。所提出的估计器基于最大 DFT 谱线和两条离散时间傅里叶变换 (DTFT) 谱线的插值，并且可以使用矩形窗口和最大旁瓣衰减 (MSD) 窗口进行操作。在粗略估计步骤中，使用了建议的带有 MSD 窗口的估计器。根据粗略估计的值，去除负频谱分量。在精细估计步骤中，使用所提出的具有矩形窗口的估计器来实现 Cramer-Rao 下界 (CRLB)。仿真结果表明，该算法的性能优于AM算法、Candan算法、Djukanovic算法和FDIAM算法。