【摘要】 本文研究了DFT谐波分析中A/D转换器量化效应对谐波幅度和相位分析准确度的影响,并导出了误差传递关系式;讨论了在信号、系数(三角函数)量化效应同时存在时的谐波分析误差,并利用微小标准偏差准则研究了如何根据A/D转换器的量化位数来合理选择系数的量化位数,使系数量化引起的谐波分析误差与A/D转换器量化引起的误差相比可以忽略不计,同时又使DFT的计算量最小。结果表明,系数量化位数高于信号量化位数2～4位就已足够。更多还原

【Abstract】 The effect of A/D converter quantization error to the accuracy in Discrete Fourier Transform(DFT)is analyzed and the errors of harmonic measurement caused by the quantizations of signal and coefficients are obtained in this paper.Futhe-rmore,the selection of the least number of quantized bits for coefficients is described,in which the error caused by the quantization of the coefficients is negligible compared with that of sampled data.The result shows that the quantized bit for coefficients is sufficient to be 2-4 times larger than the bit of sampled data in binary.更多还原