Numerical differentiation based parameter measurement algorithms for sinusoidal signals in noises

Abstract

A novel algorithm for signal parameters such as frequency, amplitude and phase estimation in noises is proposed in this paper. The proposed algorithm is based on numerical differentiation and Lagrange interpolation and need 2 samples and computation process, one of which is used for frequency estimation in half cycle of the signal and another of which is used for amplitude and phase estimation in another half cycle. With an initial sample frequency of 512 /spl times/ 50 Hz, the signal is sampled and the frequency of the signal with white Gaussian noises is estimated at an accuracy of 0.001% over a range of 1 Hz to 50 kHz. With another sample frequency based on the estimated frequency, the signal is once again sampled and the amplitude of the signal is estimated an accuracy of 0.002% over a range of 1 V to 200 V and the phase angle of the signal is estimated an accuracy of 0.002% over a range of 0 to 360. Simulation analysis is accomplished with a sinusoidal signal in Matlab software, and the results of the simulation are satisfactory.