xDSL modem having DMT symbol boundary detection

摘要

An xDSL communication system using Discrete Multi-tone (DMT) symbols sent over a channel. The magnitude of the channel's frequency-domain equalizing filter is normalized, leaving only phase information. The inverse discrete fourier transform of the normalized filter gives a peak at a position which corresponds to the group time delay of the transmitted DMT symbol. Identification of the symbol boundary facilitates synchronization of the receiver symbol sample phase to the transmitter symbol phase.