An extension of the discrete Fourier transform
Rashid Ansari · IEEE Transactions on Circuits and Systems · 1985
An extension of the Discrete Fourier Transform (DFT) is defined as a linear combination of the forward and inverse DF's of a sequence. The coefficients of the linear combinations can be chosen to define a real transform for a real sequence. A fast algorithm can be used to compute the transform for a sequence whose length is a power of two.