Patent ID: 7477683

Claim:
A method for digital communication, comprising: generating time-domain symbols having a predetermined symbol duration in accordance with a discrete multi-tone (DMT) modulation scheme; adding a cyclic extension having an extension length CE to each of the time-domain symbols so as to form data blocks having a block length that is not an integer multiple of the symbol duration; generating, on one or more tones of the DMT modulation scheme, a training pattern that is periodic, with a period equal to the symbol duration, over a sequence of the data blocks that includes the cyclic extension, by modulating the one or more tones with a succession of training symbols and applying a respective phase rotation to each of the training symbols so as to increment the phase of each successive training symbol by an amount proportional to the extension length CE of the cyclic extension; transmitting the sequence of the data blocks over a communication channel to a receiver; and processing the training pattern at the receiver so as to determine a response of the channel to the one or more tones.