摘要
分数阶Fourier变换是对经典Fourier变换的推广.根据信号瞬时相关函数、点谱相关函数、Wigner分布和模糊函数这4种信号表示方法之间的Fourier变换关系,基于二维分数阶Fourier变换,给出一种新的分数阶时频分布,它表征了信号的局部时间/频偏和局部频率/时延特性,进一步讨论该分布函数的主要性质.最后给出它在线性调频(chirp)信号检测中应用的仿真结果.
Fractional Fourier transform can be considered as generalization of the Fourier transform. Four basic quadratic signal representations, i, e., signal correlation function, spectral correlation function, Wigner distribution, and ambiguity function, can be interpreted with Fourier transform. A new time-frequency distribution function based on 2D fractional Fourier transform is presented. The distributions have partial time/ frequency-lag and partial frequency/time-lag characteristics of signals. Main properties of the distribution function are discussed. Simulations show that the described distribution can detect chirp signal.
出处
《上海大学学报（自然科学版）》
CAS
CSCD
北大核心
2007年第4期444-448,共5页
Journal of Shanghai University:Natural Science Edition
基金
国家自然科学基金资助项目(60672160)
上海市教委发展基金资助项目(217635)
