Targeted rectangular conditioning

Patent metadata

Field	Value
Publication number	US-10826560-B2
Application number	US-201615760461-A
Country	US
Kind code	B2
Filing date	Oct 3, 2016
Priority date	Oct 6, 2015
Publication date	Nov 3, 2020
Grant date	Nov 3, 2020

Abstract

A vectoring controller for configuring a vectoring processor that jointly processes DMT communication signals to be transmitted over, or received from, a plurality of N subscriber lines according to a vectoring matrix. In accordance with an embodiment, the vectoring controller is configured, for given ones of a plurality of tones, to enable the given tone for direct data communication over a first set of N−Mk targeted lines out of the plurality of N subscriber lines, and to disable the given tone for direct data communication over a second disjoint set of Mk supporting lines out of the plurality of N subscriber lines, Mk denoting a non-null positive integer. The vectoring controller is further configured to configure the vectoring matrix to use an available transmit or receive power at the given tone over the second set of Mk supporting lines for further enhancement of data signal gains at the given tone over the first set of N−Mk targeted lines.

First claim

The invention claimed is:

1. A vectoring controller configured to, for given ones of a plurality of tones:
characterize a N×N channel matrix, comprising far-end coupling coefficients between a plurality of N subscriber lines at the given tone, as being ill-conditioned;
determine a first set of N−Mk targeted lines and a second disjoint set of Mk supporting lines out of the plurality of N subscriber lines such that a (N−Mk)×N reduced channel matrix, comprising a far-end coupling tone coefficients from the plurality of N subscriber lines into the first set of N−Mk targeted lines at the given tone, is well-conditioned, Mk denoting a non-null positive integer;
enable the given tone for direct data communication over the first set of N−Mk targeted lines, and disable the given tone for direct data communication over the second set of Mk supporting lines;
configure a vectoring matrix to use an available transmit power at the given tone over the second set of Mk supporting lines to enhance data signal gains at the given tone over the first set of N-Mk targeted lines; and
jointly process discrete multi-tone (DMT) communication signals to be transmitted over the plurality of N subscriber lines according to the vectoring matrix.

2. A vectoring controller according to claim 1 , wherein the vectoring controller is further configured to balance at least one line metric across the plurality of N subscriber lines when iterating through the plurality of tones in sequence.

3. A vectoring controller according to claim 1 , wherein the configured vectoring matrix is a rectangular N×(N−Mk) precoding matrix with at least one non-null off-diagonal precoding coefficient for the respective Mk matrix rows corresponding to the second set of Mk supporting lines.

4. A vectoring controller according to claim 3 , wherein the configured rectangular vectoring matrix is a generalized inverse matrix of a (N−Mk)×N reduced channel matrix.

5. A vectoring controller according to claim 4 , wherein the generalized inverse matrix is a Moore-Penrose pseudo-inverse of the (N−Mk)×N reduced channel matrix.

6. A vectoring controller according to claim 1 , wherein
the vectoring controller is further configured to iterate through the plurality of tones in sequence, and
to update respective line metrics achieved over the plurality of N subscriber lines given the enabling and disabling of the tones and the configured vectoring matrices in each tone iteration, and to determine the first and second sets of lines based on the updated line metrics.

7. A vectoring controller according to claim 6 , wherein the vectoring controller is further configured to assign at least one subscriber line of the plurality of N subscriber lines, whose updated line metric exceeds a given line metric target, to the second set of Mk supporting lines for at least one subsequent tone iteration.

8. A vectoring controller according to claim 6 , wherein the vectoring controller is further configured to assign at least one subscriber line of the plurality of N subscriber lines, whose updated line metric exceeds by a given margin at least one updated line metric of at least one further subscriber line of the plurality of N subscriber lines, to the second set of Mk supporting lines for at least one subsequent tone iteration.

9. A vectoring controller according to claim 6 , wherein the line metrics are data rates.

10. An access node configured to provide broadband communication services to subscribers, and comprising a vectoring controller according to claim 1 .

11. A vectoring controller configured to, for given ones of a plurality of tones:
characterize a N×N channel matrix, comprising far-end coupling coefficients between a plurality of N subscriber lines at the given tone, as being ill-conditioned;
determine a first set of N−Mk targeted lines and a second disjoint set of Mk supporting lines out of the plurality of N subscriber lines such that a (N−Mk)×N reduced channel matrix, comprising a far-end coupling tone coefficients from the plurality of N subscriber lines into the first set of N−Mk targeted lines at the given tone, is well-conditioned, Mk denoting a non-null positive integer;
enable the given tone for direct data communication over the first set of N−Mk targeted lines, and disable the given tone for direct data communication over the second set of Mk supporting lines;
configure a vectoring matrix to use an available receive power at the given tone over the second set of Mk supporting lines to enhance data signal gains over the given tone at the first set of N−Mk targeted lines; and
jointly process discrete multi-tone (DMT) communication signals to be received over the plurality of N subscriber lines according to the vectoring matrix.

12. A vectoring controller according to claim 11 , wherein the configured vectoring matrix is a rectangular (N−Mk)×N postcoding matrix with at least one non-null off-diagonal postcoding coefficient for a respective Mk matrix columns corresponding to the second set of Mk supporting lines.

13. A vectoring controller according to claim 12 , wherein the configured rectangular vectoring matrix is a generalized inverse matrix of a N×(N−Mk) reduced channel matrix.

14. A vectoring controller according to claim 13 , wherein the generalized inverse matrix is a Moore-Penrose pseudo-inverse of the N×(N−Mk) reduced channel matrix.

15. A vectoring controller according to claim 11 , wherein the vectoring controller is further configured to balance at least one line metric across the plurality of N subscriber lines when iterating through the plurality of tones in sequence.

16. A vectoring controller according to claim 11 , wherein the vectoring controller is further configured to iterate through the plurality of tones in sequence, and to update respective line metrics achieved over the plurality of N subscriber lines given the enabling and disabling tones and the configured vectoring matrices in each tone iteration, and to determine the first and second sets of lines based on the updated line metrics.

17. A vectoring controller according to claim 16 , wherein the vectoring controller is further configured to assign at least one subscriber line of the plurality of N subscriber lines, whose updated line metric exceeds a given line metric target, to the second set of Mk supporting lines for at least one subsequent tone iteration.

18. A vectoring controller according to claim 16 , wherein the vectoring controller is further configured to assign at least one subscriber line of the plurality of N subscriber lines, whose updated line metric exceeds by a given margin at least one updated line metric of at least one further subscriber line of the plurality of N subscriber lines, to the second set of Mk supporting lines for at least one subsequent tone iteration.

19. A vectoring controller according to claim 16 , wherein the line metrics are data rates.

20. An access node configured to provide broadband communication services to subscribers, and comprising a vectoring controller according to claim 11 .

21. A method for configuring a vectoring processor comprising, for given ones of a plurality of tones:
characterizing a N×N channel matrix, comprising far-end coupling coefficients between a plurality of N subscriber lines at a given tone, as being ill-conditioned;
determining a first set of N−Mk targeted lines and a second disjoint set of Mk supporting lines out of the plurality of N subscriber lines such that a (N−Mk)×N reduced channel matrix, comprising a far-end

Assignees

• Alcatel Lucent
• Nokia America Corp

Inventors

• Tsiaflakis Paschalis
• Nuzman Carl
• Maes Jochen

Classifications

• H04B3/487 Primary

  Testing crosstalk effects · CPC title

• H04B3/32 Primary

  Reducing cross-talk, e.g. by compensating · CPC title

• H04J11/0033

  by pre-cancellation of known interference, e.g. using a matched filter, dirty paper coder or Thomlinson-Harashima precoder (correlative coding in synchronous or start-stop systems H04L25/497) · CPC title

• H04J11/0046

  using joint detection algorithms · CPC title