Egress reduction by intra-symbol windowing in DMT-based transmitters

Discrete multi tone (DMT) uses an inverse discrete Fourier transform (IDFT) to modulate data on the carriers. The rather high side lobes of the IDFT filter bank can lead to spurious emissions in unauthorised frequency bands. Applying a window function within the DMT symbol alleviates this, but introduces distortions that are generally not easy to compensate. In this paper a special class of window functions is derived for which this compensation only requires a modest amount of processing at the receiver.