Abstract: According to the high precision subdivision requirements of metrological grating Moiré fringes, a subdivision method of grating based on ADC amplitude sampling and phase resolution was established. And the simulation model of this subdivision method was established to convert the sin & cosine signals into two quadrature encoding signals after positive cotangent transforming, the amplitude sampling phase dividing in fixed step size and other processing method. The results of simulation experiments show that the interpolation of this method is related to accuracy of ADC with the ideal signal inputting and the maximal interpolation can be increased up to 1000 by improving the ADC sampling digit. The simulation experiment also verified that subdivision precision mainly depends on the signal quality by adding noise interference including unequal amplitude error, quadrature phase shift error and high order harmonic components to the dynamic sin & cosine ideal signals.

Key words: Simulation modeling, Amplitude sampling, Phase resolution, Subdivision of moire fringe, Noise interference