A method of high‐precision frequency detection with FFT
Makoto Tabei, M. Ueda · Electronics and Communications in Japan (Part I Communications) · 1988
Abstract Except for the nonlinear complex method such as MEM, there has not been known a method to determine the frequency with a high accuracy from the short wave train. Generally, it is considered that the frequency resolution in FFT is of the order of the step in the frequency. This paper attempts to derive a correction formula for FFT results by which the frequency, amplitude and phase of the arbitrary input signal with discrete frequencies can be calculated easily and with a high accuracy. The effect of the noise on the accuracy is discussed in the practical measurement condition, and it is shown by theory and numerical experiment for the case of white noise that the accuracy is linearly dependent on the noise ratio.