Two-stage symbol alignment method for ADSL transmission in the presence of TCM-ISDN interferers

摘要

Method embodiments for achieving hyperframe symbol synchronization are disclosed, along with device and system embodiments for implementing such methods. In one embodiment, the method comprises: receiving a pilot signal having at least two phase states; measuring the pilot signal as a sequence of measured symbols; and determining an alignment offset upon detecting between adjacent measure symbols a phase difference greater than a predetermined threshold. The alignment offset determination may include: forming a data field of four measured symbols around the detected phase difference; searching for the position of a two-symbol window in the data field that maximizes a phase difference; and calculating the alignment offset from this position.