中国物理B ›› 2010, Vol. 19 ›› Issue (7): 74201-074201.doi: 10.1088/1674-1056/19/7/074201
石鹏, 曹国威, 李永平
Shi Peng(石鹏) , Cao Guo-Wei(曹国威), and Li Yong-Ping(李永平)†
摘要: Two physical interpretations of chirp transform related to Fresnel diffraction and Wigner distribution function are given. The chirp transform can be regarded as a Fresnel diffraction observed on a spherical tangent to the diffraction plane, or a rotation and stretching transformation of the Wigner distribution function space. A general fast algorithm for the numerical calculation of chirp transform is developed by employing two fast Fourier transform algorithms. The algorithm, by which a good evaluation can be achieved, unifies the calculations of Fresnel diffraction, arbitrary fractional-order Fourier transforms and other scalar diffraction systems. The algorithm is used to calculate the Fourier transform of a Gaussian function and the Fourier transform, the Fresnel transform, the Fractional-order Fourier transforms of a rectangle function to evaluate the performance of this algorithm. The calculated results are in good agreement with the analytical results, both in the amplitude and phase.
中图分类号: (Modulation, tuning, and mode locking)