Time-domain equalizer for discrete multi-tone based DSL systems with cyclic extension in training

摘要

The present invention provides for a method and system to implement time-domain equalizer (TEQ) training to shorten the channel impulse response of twisted copper lines for DMT-based VDSL systems. The coefficients of TEQ are trained when training signal has cyclic extension (CE), such as specified in current VDSL standard and proposed for VDSL2. The invention effects frame alignment and removal of CE to effectively permit implementation of TEQ training for VDSL where the training signal has cyclic extension. The advantage of this new invent is that Intersymbol interference (ISI) can be reduced in the current VDSL systems and FFT (Fast Fourier Transform) can be applied in place of presently used DFT (Direct Fourier Transform) for TEQ training. Use of the present invention in effectively implementing TEQ training in systems having cyclic extension results in reduced complexity, power saving, reduced memory requirements in terms of code space, and cost savings