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A Simple and Effective Algorithm for Sinusoidal Frequency Estimation

Frequency estimation plays a very important position in underwater noise monitoring. The estimation method based on complex modulation (ZOOMFFT) can estimate the frequency with a sufficiently specified high sampling frequency within a narrow-band frequency signal spectrum. In this paper, the complex modulation principle is described, and its effectivity in reducing workload and improving accuracy is shown by simulation. By the complex modulation, down-sampling and FFT operating, the figure of simulation result is shown and then the validation of this method in improving the frequency estimation accuracy is done. It is easy to be implemented by microcontroller and can work for underwater noise analyze.