Efficient computation of the DFT and IDFT in communication systems using Discrete Multitone modulation

The Discrete Fourier Transform (DFT) and the Inverse Discrete Fourier Transform (IDFT) are commonly used in signal processing applications, in particular in digital communication systems using the multi-carrier modulation principle. In such systems an IDFT is computed at the transmitter end, and a DFT at the receiver end. This paper examines a technique of computations, for which only negligible differences appear between the DFT and the IDFT calculations while the number of arithmetic operations required is substantially reduced. This offers significant advantages for the design of an IDFT/DFT processor for Discrete Multitone (DMT) systems.