Near-end crosstalk cancellation in xDSL systems

An algorithm for reducing the computational load in near-end crosstalk (NEXT) cancellation is proposed. The algorithm first detects the major NEXT sources by taking the cross correlation of the adjacent transmitted signals with the received signal. A fast method for estimating the cross correlation is utilized to speed up the detection process. Upon detection, an adaptive filter cancels each NEXT source. The detection and cancellation are done simultaneously as the algorithm progresses. This helps the smaller NEXT signals to be detected as the larger NEXT signals are cancelled out.