Fractional fourier transform. Presenter: Hong Wen-Chih. Outline. Introduction Definition of fractional fourier transform Linear canonical transform Implementation of FRFT/LCT The Direct Computation DFT-like Method Chirp Convolution Method Discrete fractional fourier transform
In time-frequency representation
And what if angle is not multiple of π/2 ?
Time-frequency plane and a set of coordinates
rotated by angle α relative to the original coordinates
Note: do four times FT will equal to do nothing
(chirp multi.) (FT) (scaling) (chirp multi.)
when 2D+(0, ), D is integer (i.e., sin > 0)
when 2D+(, 0), D is integer (i.e., sin < 0)
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