Single-ended vectored DSL system

A single-ended vectoring system comprising:

• a plurality of near end cross talk (“NEXT”) receivers that receive signals from a corresponding plurality of victim loops of a DSL system, wherein the NEXT receiver are collocated with the transmitters of one or more disturber loops of the DSL system;
• a single-ended vectoring control entity (“SVCE”) that receives NEXT components from the NEXT receivers and uses the NEXT components to generate NEXT multiple input multiple output (“MIMO”) channel matrix coefficients;
• and
• a pre-coder that receives an encoded data stream for transmission and uses the received MIMO channel matrix coefficients received from the SVCE to modulate each subcarrier of the Discrete Multi-Tone (“DMT”) signal with a NEXT cancellation signal for each victim loop of the plurality of victim loops that reduces both NEXT and far end cross talk (FEXT).

A method comprising:

• receiving, at respective receivers located at a transmit side of one or more victim loops, a measure of near-end crosstalk (NEXT) sourced from one or more disturber loops of a DSL system;
• demodulating the received measure of NEXT into constituent subcarrier components;
• correlating transmissions signals of the one or more disturber loops, on a per subcarrier basis, with the corresponding demodulated components of the received measure of NEXT;
• estimating a NEXT cancellation vector based on the correlation;
• and
• using the cancellation vector to generate a respective NEXT cancellation signal to be added to each victim loop, where the cancellation signal for a particular victim loop destructively interferes with the near-end crosstalk of that victim loop, wherein adding the respective cancellation signal to each victim loop comprises:
• mapping each victim loop signal to a corresponding constellation point;
• precoding the constellation points using the cancellation signal;
• and
• using the pre-coded constellation points to modulate each victim loop signal.