Alcatel Lucent

Provenance Asset Group LLC

Dirk Vanderhaegen

Danny Van Bruyssel

Carl Jeremy Nuzman

Jochen Maes

Michael Timmers

Jan Sylvia Verlinden

Bart Hillaert

Adriaan J De Lind Van Wijngaarden

Paschalis Tsiaflakis

Hungkei Keith Chow

Koen De Schepper

Frank C Defoort

Michael Peeters

Geert Bert Ysebaert

Wim Troch

Francois Fredricx

Thomas Mermans

Thomas J G Mermans

Wim Van Damme

Jan Verlinden

Paul Spruyt

In accordance with an embodiment, the method includes detecting an update event whereupon a precoder needs to be updated, sending signal adjustment information to a receiver remotely coupled to a subscriber line out of the plurality of subscriber lines indicative of a signal compensation factor to be applied to a receive communication signal to compensate for a channel bias caused by the scheduled precoder update, and time-coordinating the precoder update with the enforcement of the signal compensation factor at the receiver.

Gain adaptation for downstream vectoring systems

The method includes inputting first groups of frequency samples to be transmitted over, respectively received from, first and second subsets of subscriber lines at respective first tones and following a first group selection order, alternated with mirrored second groups of frequency samples to be transmitted over, respectively received from, the second subset of subscriber lines at respective mirrored second tones of the first tones, and following a mirrored second group selection order of the first group selection order, to a vectoring processor for joint mitigation of first crosstalk present over the first and second subsets of subscriber lines at the respective first tones and second crosstalk present over the second subset of subscriber lines at the respective second tones. The first tones are common to the first and second transmit spectra. Mirroring is with respect to a folding frequency derived from a reference sampling frequency applicable to the first subset of subscriber lines.

Crosstalk mitigation for out-of-band tones

In accordance with an embodiment the method includes temporarily configuring the vector processor with a new set of vectoring coefficients during one or more selected symbol positions; restoring the current set of vectoring coefficients outside the one or more selected symbol positions; obtaining at least one error measure over respectively at least one line of the group of vectored lines during the one or more selected symbol positions; and determining a suitability indication for the new set of vectoring coefficients based on the obtained at least one error measure.

Method and device for controlling a vector processor

In accordance with an embodiment, the vectoring controller is configured to iterate through successive crosstalk acquisition cycles and, within respective ones of the crosstalk acquisition cycles, to configure sequences of crosstalk probing symbols for transmission over the respective communication lines, to receive sequences of error samples as successively measured by respective receivers coupled to the respective communication lines while the sequences of crosstalk probing symbols are being transmitted, and to determine crosstalk estimates between the respective communication lines based on the sequences of error samples. The vectoring controller is further configured to randomize the successive sequences of crosstalk probing symbols used during the successive crosstalk acquisition cycles, and to iteratively configure the vectoring processor based on the successive crosstalk estimates.

Randomization of crosstalk probing signals

At least one crosstalk probing sequence out of a set of orthogonal crosstalk probing sequences is assigned to the at least one respective disturber line for modulation at the given carrier frequency of at least one respective sequence of crosstalk probing symbols, and error samples are successively measured by a receiver coupled to the victim line at the given carrier frequency while the at least one sequence of crosstalk probing symbols are being transmitted over the at least one respective disturber line are fed back for crosstalk estimation. The received error samples are next correlated with at least one unassigned crosstalk probing sequence out of the set of orthogonal crosstalk probing sequences for detection of a demapping error in the received error samples.

Detection of demapping errors

A crosstalk emulator for a cable, preferably a xDSL telecommunication cable, represented by several emulation paths each comprising a first segment (L/L) serially connected to a second segment (L/L) on a printed circuit board PCB. The first and second segments of a same emulation path form an angle, e.g. of about 90 degrees, at their junction point. All the emulation paths have a same length and preferably run in parallel over the PCB. As a result, each emulation path crosses only once (X) any other emulation path at a cross-point. Furthermore, the area occupied by the crosstalk emulator on the PCB is reduced with respect to a matrix topology, whereby the present topology can easily be extended to large numbers of couplings, allowing design guidance for a passive coupling emulator with a large amount of coupling elements (CP) at the cross-points.

Crosstalk emulator for xDSL cable

Method for dealing with an anomalous condition in a local network including a power injector, said method comprising connecting the power injector to a communication line extending between the local network and a remote device, said power injector being capable of injecting power on the communication line, for reverse powering a remote device located outside the local network, and for powering any local device that is regularly connected to the communication line; said communication line being used for exchanging data between the remote device and the local network; recognizing when a power consumption behavior of the power injector deviates from a characteristic power consumption behavior of said remote device and of any regularly connected local device; and controlling the power injector when a deviation is recognized.

Method for dealing with anomalous conditions in a reverse power network, and power injector for use in such a method

In an embodiment the method includes, at a transmit side, grouping carriers into carrier groups, and selecting a group constellation diagram for modulation of the carriers of a given carrier group. The selected group constellation diagram is built as a hierarchical sum of I super-imposed constellations vectors having predefined decreasing powers with the P strongest and the Q weakest constellation vectors being omitted. The carriers of the carrier group are modulated by means of the selected group constellation diagram, and P and/or Q parameters per carrier group and per multi-carrier data symbol are adjusted.

Hierarchical and adaptive multi-carrier digital modulation and demodulation

At least one example embodiment discloses a method of initializing a plurality of communication paths in a system. The method includes obtaining a first matrix from a storage medium, the first matrix including at least one channel sub-matrix of the system associated with a subset of the plurality of communication paths, obtaining an indication of which communication paths are to become active and determining, after the obtaining the indication, new compensation coefficients based on the at least one channel sub-matrix and active compensation coefficients, the active compensation coefficients for compensating for crosstalk between the active communication paths prior to the number of active communication paths changing.

Methods and systems for activating and deactivating communication paths

In one embodiment, the access node includes a vectoring control unit for estimating crosstalk coefficients between a set of subscriber lines based on crosstalk measurements carried out over the set of subscriber lines during a crosstalk measurement phase, and a vectoring processing unit for jointly processing, for crosstalk mitigation, signals to be transmitted over, or received from, the set of subscriber lines based on the estimated crosstalk coefficients. The access node further includes a controller configured to either postpone the execution of power adaptation over a particular line out of the set of subscriber lines after the completion of the crosstalk measurement phase, or to postpone the crosstalk measurement phase after the completion of power adaptation over the particular line.

Power adaptation avoidance during crosstalk measurements

A crosstalk cancellation device cancels crosstalk noise of at most M disturbing communication lines in a victim communication line forming part of a vectoring group. The crosstalk cancellation device gradually decreases the cancellation depth of a cancelled disturbing communication line in the victim communication line upon a crosstalk noise variation in the vectoring group requiring cancellation of crosstalk noise of a not yet cancelled disturbing communication line in the victim communication line.

Crosstalk cancellation device and method with improved vectoring stabilisation

In a multi-tone data transmission system, data are modulated on a set of M tones for being transmitted between a transmitter and a receiver. The data retransmission request device in such system is adapted to request retransmission of a data transmission unit that is hierarchically modulated at a particular hierarchical level and that is modulated on a particular group of N tones, N being a positive integer value greater than one and smaller than or equal to M.

Data retransmission request device, a data transmitter, and a data retransmission method for multi-tone systems

In one embodiment, the line termination card includes a data output terminal configured to output a data sequence. The card further includes a vectoring entity configured to parse and encode the data sequence into frequency samples according to a carrier loading parameter, configured to scale the frequency samples into scaled frequency samples according to a carrier scaling parameter, and, configured to process the scaled frequency samples for crosstalk compensation. A controller is configured to adjust the carrier loading parameter and the carrier scaling parameter, and a forwarder is coupled to the data output terminal and to the controller. The forwarder is configured to forward the data sequence, the carrier loading parameter and the carrier scaling parameter towards a further line termination card.

Joint signal processing across a plurality of line termination cards

In a network for digital data packet transmission, quality records are stored in a memory. Each of the quality records is indicative for a reception quality being sensed of one or more received data packets. Thereupon, upon overflow of the memory, one or more of the quality records is discarded from the memory. For at least one of the quality records, discarding weights are generated as a function of at least one of the quality records and associated to the quality records. Hereby, upon such overflow, the discarding weights are taken into account in predefined rules and conditions according to which the discarding of the quality records is performed.

Method for monitoring impulse noise

In a network for digital data packet transmission, reception quality of received data packets is sensed () by a remote terminal (). Thereupon, a bit string indicative for the sensed reception quality is generated (). This bit string or a compressed version of this bit string is transferred () in real-time over a management channel to a first central processing unit () in a network node () where the bit string is compacted or processed. By processing the bit string, the first central processing unit () may determine impulse noise characteristics. Alternatively, the bit string or a compressed or compacted version thereof may be forwarded to a second central processing unit () in a network manager () that processes the bit string and determines impulse noise characteristics.

Growing community of inventors

Wemmel, Belgium

Dirk Vanderhaegen