L. Yu et al., THE LAGUERRE-GAUSSIAN SERIES REPRESENTATION OF 2-DIMENSIONAL FRACTIONAL FOURIER-TRANSFORM, Journal of physics. A, mathematical and general (Print), 31(46), 1998, pp. 9353-9357
In this paper the Laguerre-Gaussian (LG) series representation of the
two-dimensional fractional Fourier transform is derived from conventio
nal ordinary Fourier transform in polar coordinates. The kernel of thi
s series representation is constituted by Laguerre-Gaussian functions,
from which the series representation of a fractional Hankel transform
can bt:easily derived. The connection between the gradient-index medi
um and the LG series representation is illustrated as an example of it
s applications.