摘要
目的研究不仅适用于离散实信号、解析信号,同时适用于通信系统中常常用到的正交信号的一般离散时频分布(DTFD)的方法及其周期、混叠、计算复杂度等特性。方法根据Cohen类与Wigner分布的关系和正交信号的频谱关于原点不对称特性,通过离散Wigner分布和频域插值获得一般反混DTFD。结果提出了一种适用于离散实信号、解析信号和正交信号的DTFD的快速算法;在不增加计算复杂度的情况下,具有反混叠特性。结论所给出的方法能够对实际工程中应用的正交信号进行时频分析,获得了良好的效果。
Aim To study the discrete time-frequency distributions（DTFDs） of quadrature signals and the characteristics in terms of period,aliasing and computation complexity,which is widely used in discreting real,analytic signals and quadrature signals commonly used in communication systems.Methods According to the relationship between Cohenclass and Wigner distribution（WD） and the unsymmetrical property about the origin for negative and positive frequency components of quadrature signals,an anti-aliasing approach for DTFDs is proposed by discretizing the WD and interpolation in frequency domain.Results A fast algorithm of DTFDs and an anti-aliasing approach for DTFDs suitable for real,analytic and quadrature signals is presented and the complexity of computation is not increased.Conclusion Some real world examples analyzed show the better effects of the proposed method.
出处
《西北大学学报（自然科学版）》
CAS
CSCD
北大核心
2011年第1期48-52,共5页
Journal of Northwest University（Natural Science Edition）
基金
国家科技重大专项基金资助项目(2010ZX03006-002-03)
国家自然科学基金资助项目(60872139)
关键词
离散时频分布
快速算法
正交信号
混叠
discrete time-frequency distribution
fast algorithm
quadrature signal
aliasing
