Nyquist采样频率下的频谱失真与采样定理

SPECTRAL DISTORTIONS AT SAMPLING RATE AND A NEW EXPRESSION OF SAMPLING THEOREM

本文通过在 Nyquist采样率下对信号的频谱是否发生失真 ,发生了怎样的失真的讨论 ,分析了在进行离散傅立叶变换 ( DFT)时 ,采样定理在其边界条件下进行信号处理时存在的问题 .展示了在该条件下频谱发生严重失真的形式和程度 ,最后从无失真地恢复时域信号 x( t)的角度讨论了 DFT意义下采样定理的表述 .

This paper makes an investigation into the performance of Nquist sampling rate when DFT is conducted at this rate in order to study whether spectral distortions will take place and what patterns and magnitudes of gross distortions may take shape.Then,a new expression of sampling theorem is recommended with a view to reconstructing the original time domain signal x(t) on implementation of DFT.