A new sine-fitting algorithm for accurate amplitude and phase measurements in two channel acquisition systems

Sine-fitting algorithms are very accurate methods to estimate the parameters (amplitude, phase, frequency and DC component) of a digitized sinusoidal signal. In this paper, the standardized algorithms are improved, producing a new algorithm to estimate the sinewave parameters of two acquired sine signals sharing a common frequency. This new algorithm can be used for example in impedance measurements or in the accurate frequency characterization of linear systems by measuring its input and output and varying the input signal frequency.