Method and apparatus for equalization and crosstalk mitigation

A multi-channel communication system configured to reduce noise comprising:

• one or more transmitters configured to transmit a first signal on a first channel and a second signal on a second channel;
• and
• a first receiver configured to receive a third signal on the first channel and a second receiver configured to receiver a fourth signal on the second channel, wherein the third signal comprises the first signal and a first interference component and the fourth signal comprises the second signal and a second interference component wherein;
• the first receiver comprises:
• a first feedback filter loop configured to receive the third signal and reduce interference on the third signal, the output of the first feedback filter loop comprising a first feedback filter loop output;
• a first decision device having a first decision device output configured as part of the first feedback filter loop;
• a first device configured to receive a second cancellation signal from the second receiver and combine the second cancellation signal with the first feedback filter loop output;
• a first filter configured to receive at least the decision device output and generate a first cancellation signal;
• and
• the second receiver comprises:
• a second feedback filter loop configured to receive the fourth signal and reduce interference on the fourth signal, the output of the second feedback filter loop comprising a second feedback filter loop output;
• a second decision device having a second decision device output configured as part of the second feedback filter loop;
• a second device configured to receive the first cancellation signal from the first receiver and combine the first cancellation signal with the first feedback filter loop output;
• and
• a second filter configured to receive at least the second decision device output and generate the second cancellation signal.

A receiver for use in a multi-channel communication system to cancel coupling on a transmitted signal and reduce intersymbol interference, wherein a distorted version of the transmitted signal and FEXT coupling comprise a combined signal, the receiver comprising:

• a first device configured to receive and combine a feedback signal with the combined signal to create a decision device input signal;
• a decision device configured to process the decision device input signal to generate a discrete output;
• a decision feedback equalizer configured to receive and process the discrete output to generate an equalizer output;
• a second device configured to combine an incoming cancellation signal with the equalizer output to create the feedback signal;
• and
• one or more ELFEXT filters, each configured to generate an outgoing cancellation signal that is related to the discrete output, wherein the outgoing cancellation signal is tailored to cancel FEXT coupling on another channels in the multi-channel communication device.

A receiver in a multi-receiver system configured to receive two or more signals via two or more channels, each respective receiver comprising:

• an input configured to accept a received signal;
• a decision device configured to quantize a decision device input signal to one of two or more decision values, wherein the decision device input signal is based on the received signal;
• a first filter configured to process the decision values to create a first filtered signal;
• one or more second filters configured to process the decision values and the first filtered signal to create an outgoing cancellation signal tailored to cancel coupling on one or more other channels;
• one or more devices configured to:
• receive one or more incoming cancellation signals from other receivers in the multi-receiver system;
• and
• process the one or more incoming cancellation signals, the first filtered signal, and the received signal to cancel unwanted coupling in the received signal.

A method for reducing interference in a multi-channel communication system having two or more receivers and two or more channels, the method of the first receiver comprising:

• receiving a first signal on a first channel with a first receiver and a second signal on a second channel with a second receiver;
• combining a feedback signal with the first received signal to create a first combined signal;
• processing the first combined signal to reduce intersymbol interference in the first combined signal to create a processed signal, the interference created by passage of the first signal through the first channel;
• combining the processed signal with at least a first cancellation signal received from at least the second receiver to create a feedback signal;
• combining the feedback signal with the first combined signal to create a second combined signal;
• and
• processing the second combined signal to generate at least a second cancellation signal.

A receiver for FEXT cancellation in a multi-channel communication system comprising:

• a feedback loop comprising:
• a first device configured to combine a received signal with a feedback signal and one or more incoming cancellation signals to create a combined signal;
• a decision device configured to process the combined signal to generate a decision output;
• a first filter configured to generate the feedback signal based on the decision output and the one or more incoming cancellation signals or a delayed version of the one or more incoming cancellation signals, wherein the one or more
• incoming cancellation signals are received from one or more other receivers in the multi-channel communication system;
• and
• one or more second filters configured to receive at least the decision output and generate one or more outgoing cancellation signals which are routed to other receivers in the multi-channel communication system.

A method for canceling coupling in a multi-channel communication system having two or more receivers comprising:

• receiving a signal over a channel;
• receiving at least one cancellation signal from at least one of the other receivers in the multi-channel communication system;
• processing the signal to account for the effect of the signal passing through the channel thereby generating a processed signal;
• combining the processed signal and the one or more cancellation signals from the other receivers to generate a feedback signal;
• combining the feedback signal with the received signal to cancel coupling in the received signal;
• and
• generating one or more outgoing cancellation signals as a result of processing the processed signal and providing at least one outgoing cancellation signals to at least one of the other receivers in the multi-channel communication system.

A system for canceling one or more FEXT signals that have coupled onto a transmitted signal to create a modified signal in a multi-channel communication device comprising:

• means for receiving the modified signal over a channel in the multi-channel communication system;
• means for combining the modified signal with a feedback signal to isolate the transmitted signal;
• means for generating the feedback signal comprising:
• means for filtering the isolated transmitted signal to create a filtered signal;
• means for receiving and combining the filtered signal and one or more cancellation signals received from other receivers in the multi-channel communication device;
• and
• means for generating one or more cancellation signals to be outputted to one or more other receivers.