Numerical differentiation based algorithms for frequency estimation of multiple signals

A high-accuracy. wide-range frequency estimation algorithm for the multi-component signals is presented in this paper. The proposed algorithm is basing on a numerical differentiation and central Lagrange interpolation. With the sample consequences. which needs at most 7 points and are sampled at a sample frequency of 256001Iz, and computation consequences, which employed a formulation proposed in this paper, the frequencies of the component J, 2 and 3 of the signal are all estimated at an error of 0.001% over 1Hz to 800kHz with the amplitudes of the component J, 2 and 3 of the signal varying from 1 V to 200 V and the phase angle of the component 1, 2 and 3 of the signal varying from 0 to 360. The proposed algorithm needs at most half cycle for the frequencies of the component 1, 2 and 3 of the signal under noisy or non-noisy conditions. A testing example with a 3 subsignals is given to illustrated the proposed algorithm in Marlab environment.