A new accurate estimator of the frequency using the three-point interpolation of DFT samples.

Frequency estimation of a sinusoidal signal is a fundamental task in signal processing in many applications such as radar, radio channels, sonar, and others. Since the frequency is the main parameter of the signal, for this reason, it is necessary to accurately detect it for the design of the measurements equipment's more accuracy. The fast Fourier transform (FFT) is widely used to analyze sinusoidal signal but it causes the problem of spectral dispersion. To reduce the effect of this problem, time windows are used. It is possible to improve the frequency estimation accuracy by using an appropriate window and an accurate frequency correction formula. A new frequency estimation algorithm based on 3-spectral DFT interpolation lines is proposed. The simulation signal was analyzed and a comparison was made of a number of windows applied to the signal such as Chebyshev, Blackman and Kaiser (β=8), and finally to test the feasibility of the proposed algorithm, a comparison was made with Jain algorithm. The simulation results showed that the proposed algorithm has a lower frequency estimation error rate. The maximum frequency estimation error was 0.002 for the proposed algorithm while 0.01 for the Jain algorithm, in addition the proposed algorithm has more stable performance and less computational complexity. [ABSTRACT FROM AUTHOR]