SYMMETRIC TRANSFORM IN SPATIAL DOMAIN AND SPATIAL FREQUENCY DOMAIN
空间城和空间频率域中的对称变换

Symmetric transform is introduced in this paper,which is a transform that performs the same operation simultaneously in both the spatial domain and spatial frequency domain.It is found that the kernel of such kind of transform must be the affine self Fourier transform function (aSFF).And an approach to construct the aSFF is also presented.Furthermore,the fractional Fourier transform (FRT) is found to be a symmetric transform.