Abstract: An apparatus comprising a receiver coupled to a digital subscriber line (DSL) between an exchange site and a customer premise equipment (CPE) and configured to send a feedback error message to train a precoder coupled to the exchange site, wherein the feedback error message comprises a plurality of error components and an indication of a quantity of bits per error component, a quantization accuracy per error component, or both. Included is a method comprising sending an error feedback message to a DSL crosstalk precoder to train the crosstalk precoder, wherein the error feedback message comprises an error vector and a quantization scaling factor of the error vector.

Abstract: An apparatus comprising a receiver coupled to a digital subscriber line (DSL) between an exchange site and a customer premise equipment (CPE) and configured to send a feedback error message to train a precoder coupled to the exchange site, wherein the feedback error message comprises a plurality of error components and an indication of a quantity of bits per error component, a quantization accuracy per error component, or both. Included is a method comprising sending an error feedback message to a DSL crosstalk precoder to train the crosstalk precoder, wherein the error feedback message comprises an error vector and a quantization scaling factor of the error vector.

Abstract: An apparatus comprising a receiver coupled to a digital subscriber line (DSL) between an exchange site and a customer premise equipment (CPE) and configured to send a feedback error message to train a precoder coupled to the exchange site, wherein the feedback error message comprises a plurality of error components and an indication of a quantity of bits per error component, a quantization accuracy per error component, or both. Included is a method comprising sending an error feedback message to a DSL crosstalk precoder to train the crosstalk precoder, wherein the error feedback message comprises an error vector and a quantization scaling factor of the error vector.

Abstract: A method for optimizing resource allocation for signal conditioning of DSL or other signal lines includes developing a signal quality metric using crosstalk interference and, optionally, signal to noise level. Use of existing pilot tone training selectively assigned to signal lines allows determination of the signal quality metric. A threshold level is selected and all signal lines having a signal quality metric above the threshold level are assigned crosstalk cancellation resources. Because the total number of signal lines requiring crosstalk cancellation is not known at the beginning, a particular threshold level may result in allocation of more than the available resources or allocation of significantly less than the available resources. When this happens the threshold level may be adjusted and the process repeated until crosstalk cancellation resources are assigned up to a usable limit.

Abstract: A method for channel estimation includes: loading a combination of signals sent on other lines over a line of a channel; measuring a signal-to-noise ratio (SNR) of the loaded line; and calculating crosstalk channels of the loaded line according to a coefficient of the combination of signals sent on other lines and the measured SNR. Accordingly, a device and system for channel estimation are provided. The technical solution of the present invention may be used for relevant systems such as an x Digital Subscriber Line (xDSL) system.

Abstract: An apparatus comprising a receiver coupled to a digital subscriber line (DSL) between an exchange site and a customer premise equipment (CPE) and configured to send a feedback error message to train a precoder coupled to the exchange site, wherein the feedback error message comprises a plurality of error components and an indication of a quantity of bits per error component, a quantization accuracy per error component, or both. Included is a method comprising sending an error feedback message to a DSL crosstalk precoder to train the crosstalk precoder, wherein the error feedback message comprises an error vector and a quantization scaling factor of the error vector.

Abstract: An apparatus comprising a transmitter at a digital subscriber line (DSL) Cabinet configured to transmit a downstream signal in a subscriber line according to a power spectral density (PSD) configuration, wherein the PSD configuration comprises a cutoff frequency based on a required data-rate of the subscriber line. Also included is an apparatus comprising at least one processor configured to implement a method comprising determining a downstream PSD for a PSD mask for a DSL, determining a cutoff frequency for the PSD profile based on a data-rate required for the DSL, and adjusting a downstream signal power on the DSL according to the PSD mask. Included is a method comprising configuring a plurality of transmitted PSDs for a plurality of Exchange deployed lines and Cabinet deployed lines by varying a plurality of cutoff frequencies corresponding to the transmitted PSDs, wherein the cutoff frequencies are varied by line, with time, or both.

Abstract: An apparatus comprising a first transceiver at a central office (CO) coupled to a second transceiver at a customer premise equipment (CPE) via a digital subscriber line (DSL), a crosstalk precoder coupled to the first transceiver at the CO, and a vectoring control entity (VCE) coupled to the transceiver via a feedback channel and to the crosstalk precoder, wherein the second transceiver comprises a noise monitor configured to detect non-crosstalk noise in a downstream signal from the CO to the CPE, and wherein the first transceiver is configured to receive a predefined special feedback signal from the second transceiver that indicates whether non-crosstalk noise is detected in the downstream signal instead of a measured error value.

Abstract: An apparatus comprising a receiver coupled to a digital subscriber line (DSL) between an exchange site and a customer premise equipment (CPE) and configured to send a feedback error message to train a precoder coupled to the exchange site, wherein the feedback error message comprises a plurality of error components and an indication of a quantity of bits per error component, a quantization accuracy per error component, or both. Included is a method comprising sending an error feedback message to a DSL crosstalk precoder to train the crosstalk precoder, wherein the error feedback message comprises an error vector and a quantization scaling factor of the error vector.

Abstract: An apparatus comprising a transmitter at a digital subscriber line (DSL) Cabinet configured to transmit a downstream signal in a subscriber line according to a power spectral density (PSD) mask, wherein the PSD mask comprises a relatively low power between a first transition frequency and a second transition frequency and a first relatively high power below about the first transition frequency and a second relatively high power above about the second transition frequency. Also included is an apparatus comprising at least one processor configured to implement a method comprising selecting a first transmission frequency and a second transmission frequency for a PSD that meets a target data-rate for transmission in a DSL, and limiting the PSD between the first transition frequency and the second transition frequency.

Abstract: A method for optimizing resource allocation for signal conditioning of DSL or other signal lines includes developing a signal quality metric using crosstalk interference and, optionally, signal to noise level. Use of existing pilot tone training selectively assigned to signal lines allows determination of the signal quality metric. A threshold level is selected and all signal lines having a signal quality metric above the threshold level are assigned crosstalk cancellation resources. Because the total number of signal lines requiring crosstalk cancellation is not known at the beginning, a particular threshold level may result in allocation of more than the available resources or allocation of significantly less than the available resources. When this happens the threshold level may be adjusted and the process repeated until crosstalk cancellation resources are assigned up to a usable limit.

Abstract: An apparatus comprising a first transceiver at a central office (CO) coupled to a second transceiver at a customer premise equipment (CPE) via a digital subscriber line (DSL), a crosstalk precoder coupled to the first transceiver at the CO, and a vectoring control entity (VCE) coupled to the transceiver via a feedback channel and to the crosstalk precoder, wherein the second transceiver comprises a noise monitor configured to detect non-crosstalk noise in a downstream signal from the CO to the CPE, and wherein the first transceiver is configured to receive a predefined special feedback signal from the second transceiver that indicates whether non-crosstalk noise is detected in the downstream signal instead of a measured error value.

Abstract: An apparatus comprising a digital subscriber line (DSL) transmitter configured to transmit a transmitter referred virtual noise for a tone in a subscriber line, wherein the transmitter referred virtual noise is based on a time history of a noise condition in the subscriber line. Also disclosed is an apparatus comprising at least one processor configured to implement a method comprising obtaining a transmitter referred virtual noise for a DSL tone using a plurality of noise condition measurements, and determining a DSL bitloading using the transmitter referred virtual noise.

Abstract: An apparatus comprising an artificial noise (AN) controller coupled to a digital subscriber line (DSL) transmitter and configured to adjust an AN level for a signal transmitted by the DSL transmitter, wherein the AN level is adjusted based on an actual signal to noise ratio (SNR) of the signal from the receiver to achieve a desired SNR for the signal. Also disclosed is a method comprising maintaining a data rate in a line at about a desired level by adjusting an AN level in a transmitted signal based on a SNR of a received signal.

Abstract: A system for processing subscriber line data signals uses a coprocessor to receive signals in a pre-determined order from a plurality of line interface cards. The coprocessor uses the pre-determined order to sort the data signals by tone and process all received signals on the same tone at the same time. Because all signals on a tone, or those on a tone with known crosstalk issues, are processed together, the signal improvement is better than prior art methods. When not used, the coprocessor may be replaced with a loop-back circuit to reduce cost when crosstalk is not a significant issue.

Abstract: An apparatus comprising a first transceiver at a central office (CO) coupled to a second transceiver at a customer premise equipment (CPE) via a digital subscriber line (DSL), a crosstalk precoder coupled to the first transceiver at the CO, and a vectoring control entity (VCE) coupled to the transceiver via a feedback channel and to the crosstalk precoder, wherein the second transceiver comprises a noise monitor configured to detect non-crosstalk noise in a downstream signal from the CO to the CPE, and wherein the first transceiver is configured to receive a predefined special feedback signal from the second transceiver that indicates whether non-crosstalk noise is detected in the downstream signal instead of a measured error value.

Abstract: A network component comprising at least one processor coupled to a memory and configured to receive a plurality of probing signals from the other end of a plurality of corresponding lines, correlate the received probing signals or their error signals with the orthogonal frequency signatures to determine the dominant crosstalk channels for each of the lines, and send a plurality of signals that correspond to the dominant crosstalk channels to a crosstalk canceller to reduce crosstalk noise in the lines, wherein each of the orthogonal frequency signatures is transmitted in a sync symbol on one of the lines, and wherein the sync symbol comprises a plurality of tones.

Abstract: A technique to shape the transmit spectrum for a digital subscriber line modem includes utilizing information indicative of crosstalk into the line of another modem. The transmit spectrum is divided by an adjustable transition frequency into a lower frequency region and a mask region. Crosstalk information about the line of the other modem is obtained and the transition frequency and the low frequency region power spectral density are adjusted to account for the data rates of both modems.

Abstract: An apparatus comprising a digital subscriber line (DSL) transmitter configured to transmit a transmitter referred virtual noise for a tone in a subscriber line, wherein the transmitter referred virtual noise is based on a time history of a noise condition in the subscriber line. Also disclosed is an apparatus comprising at least one processor configured to implement a method comprising obtaining a transmitter referred virtual noise for a DSL tone using a plurality of noise condition measurements, and determining a DSL bitloading using the transmitter referred virtual noise.

Abstract: An apparatus comprising a transmitter at a digital subscriber line (DSL) Cabinet configured to transmit a downstream signal in a subscriber line according to a power spectral density (PSD) configuration, wherein the PSD configuration comprises a cutoff frequency based on a required data-rate of the subscriber line. Also included is an apparatus comprising at least one processor configured to implement a method comprising determining a downstream PSD for a PSD mask for a DSL, determining a cutoff frequency for the PSD profile based on a data-rate required for the DSL, and adjusting a downstream signal power on the DSL according to the PSD mask. Included is a method comprising configuring a plurality of transmitted PSDs for a plurality of Exchange deployed lines and Cabinet deployed lines by varying a plurality of cutoff frequencies corresponding to the transmitted PSDs, wherein the cutoff frequencies are varied by line, with time, or both.