摘要
非均匀采样可以突破采样定理的限制,但非均匀采样信号的频谱在所有频率段均存在混叠频谱噪声,这些频谱噪声会淹没真实信号中的一些频谱幅度较小的信号,使得非均匀采样无法检测小信号。本文提出一种非均匀周期采样方法,该方法既具有非均匀采样抗混叠的特性,又具有均匀采样的消除混叠频谱噪声的特点。文中详细分析了非均匀采样产生混叠频谱噪声的原因,提出了基于非均匀周期采样的傅里叶变换方法,并给出了实验结果。理论和实验表明,非均匀周期采样方法是一种行之有效的采样方法。
The theory of nonuniformly sampling can process signals with components whose frequencies exceed the Nyquist limit. The disadvantage of nonuniformly sampling is there exists the noise in spectrum analysis. A novel nonuniform periodically sampling method is proposed in this paper. This method is very effective to suppress noise of spectrum by adopting the nonuniform periodically sampling so that it can detect the low amplitude signal. The processing procedure of nonuniform periodically sampling is presented. The results of the experiments show that it is an effective method for signal detection.
出处
《信号处理》
CSCD
北大核心
2005年第3期240-243,共4页
Journal of Signal Processing
