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.%根据计量光栅莫尔条纹信号高精度细分的要求,提出了一种基于ADC幅值采样和相位解算的光栅细分方法,并利用Simulink搭建仿真模型,使两路正余弦信号通过正余切变换、幅值采样、固定相位步长细分等处理后输出为两路正交编码信号.仿真实验表明,该细分方法在输入理想信号情况下细分倍数主要与ADC采样精度有关,提高ADC采样位数可有效提高最大细分倍数.通过在两路时变sin/cos信号中添加幅值不等、相位不正交以及高次谐波分量等干扰噪声的仿真实验,验证了该方法的细分精度与信号质量有关.
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