周期信号离散傅里叶变换的误差分析及其应用

Error analysis and application of discrete fourier transform in periodic signal ness

实际的系统都是不满足或不完全满足取样定理条件的，频率混迭是不可避免的。因此ＤＦＴ（ＦＦＴ）给出的频谱是有误差的，本文给出了误差表达式及估算方法。

An actual system does not or does not completely meet the condition of a sampling theorem,which usually causes frequency mixing.Therefore the frequerey spectrum given by DFT(FFT)is not correct.This paper puts forward the error expression and estimating method.