Method and apparatus for optimization of channel capacity in multi-line communication systems using spectrum management techniques

• US 7,356,049 B1
• Filed: 12/30/2002
• Issued: 04/08/2008
• Est. Priority Date: 12/28/2001
• Status: Expired due to Fees

• Current Assignee: Ikanos Communications Incorporated (Qualcomm, Inc.)
• Original Assignee: Ikanos Communications Incorporated (Qualcomm, Inc.)
• Inventors: Rezvani, Behrooz
• Primary Examiner(s): Nguyen; Chau
• Assistant Examiner(s): SMITH, MARCUS
• Application Number:
  US10/334,623
• Time in Patent Office: 1,926 Days
• Field of Search: 370/352, 370/465, 370/484, 370493-495, 375/222
• US Class Current: 370/484
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 5/0044 allocation of payload

Abstract

The present invention advantageously provides a method and apparatus for optimization of channel capacity in multi-line multi-tone communications such as X-DSL among subscriber lines which are bundled with one another. In an embodiment of the invention an apparatus for optimizing channel capacity of multi-tone communications effected by opposing sets of modems coupled to one another by a plurality of subscriber lines is disclosed. The apparatus includes a spectrum manager coupled to at least one of the opposing sets of modems. The spectrum manager includes: a profiler, a demand module and an optimizer. The profiler obtains from the at least one of the opposing sets of modems the spectral characteristics of each of the plurality of subscriber lines. The demand module determines for each of the plurality of subscriber lines the subscriber demand profile. The optimizer defines target parameters for at least one of bit loading, and power spectral density (PSD) for selected tones of the multi-tone communications based on the spectral characteristics from the profile module and the demand profiles from the demand module and downloads the target parameters to the at least one of the opposing sets of modems.

Claims

1. An apparatus for optimizing channel capacity in multi-tone communications effected by opposing sets of modems coupled to one another by a plurality of subscriber lines, and the apparatus comprising:

a spectrum manager coupled to at least one of the opposing sets of modems with the spectrum manager including;

a profiler to obtain from the at least one of the opposing sets of modems the spectral characteristics of each of the plurality of subscriber lines;

a demand module to determine for each of the plurality of subscriber lines the subscriber demand profile;

an interference module to determine for each of the plurality of subscriber lines at least a relative interference from remaining ones of the plurality of subscriber lines by effecting training on gap tones located within at least one of;

cross-over regions between and boundary regions proximate to the upstream and downstream spectral regions of the multi-tone communications effected on each of the plurality of subscriber lines; and

an optimizer to define target parameters for at least one of bit loading, and power spectral density (PSD) for selected tones of the multi-tone communications based on the spectral characteristics from the profile module, the demand profiles from the demand module and the relative interference determined by the interference module and to download the target parameters to the at least one of the opposing sets of modems.

2. A method for optimizing channel capacity in multi-tone communications effected across a plurality of subscriber lines by opposing sets of modems coupled thereto, and the method comprising:

obtaining the spectral characteristics of each of the plurality of subscriber lines from at least one of the opposing sets of modems;

defining target parameters including at least one of bit loading and power spectral density (PSD) for each tone of the multi-tone communications effected by the opposing sets of modems based on the spectral characteristics obtained in the obtaining act; and

identifying relatively long and short subscriber lines within the plurality of subscriber lines from the spectral characteristics obtained in the obtaining act; and

setting target parameters which effect a reduction in at least one of bit loading and PSD for high frequency tones in the relatively long subscriber lines identified in the identifying act; and

downloading to the at least one of the opposing sets of modems the target parameters defined in the defining act.

3. A method for optimizing channel capacity in multi-tone communications effected across a plurality of subscriber lines by opposing sets of modems coupled thereto, and the method comprising:

obtaining the spectral characteristics of each of the plurality of subscriber lines from at least one of the opposing sets of modems;

defining target parameters including at least one of bit loading and power spectral density (PSD) for each tone of the multi-tone communications effected by the opposing sets of modems based on the spectral characteristics obtained in the obtaining act; and

further;

identifying underutilized tones with bit loading below a threshold value within the plurality of subscriber lines from the spectral characteristics obtained in the obtaining act; and

setting target parameters which effect a reduction in at least one of bit loading and PSD for the underutilized tones identified in the identifying act; and

downloading to the at least one of the opposing sets of modems the target parameters defined in the defining act.

4. A method for optimizing channel capacity in multi-tone communications effected across a plurality of subscriber lines by opposing sets of modems coupled thereto, and the method comprising:

obtaining the spectral characteristics of each of the plurality of subscriber lines from at least one of the opposing sets of modems;

defining target parameters including at least one of bit loading and power spectral density (PSD) for each tone of the multi-tone communications effected by the opposing sets of modems based on the spectral characteristics obtained in the obtaining act; and

further;

identifying underutilized tones with bit loading below a threshold value within the plurality of subscriber lines from the spectral characteristics obtained in the obtaining act;

quantifying interference on each tone for each of the plurality of subscriber lines from remaining ones of the plurality of subscriber lines;

determining which subscriber lines among the plurality of subscriber lines exhibit data rates exceeding a corresponding subscriber demand level; and

setting target parameters which effect a reduction in at least one of bit loading and PSD for selected ones of the underutilized tones identified in the identifying act in which data rates exceed the corresponding subscriber demand level as determined in the determining act; and

downloading to the at least one of the opposing sets of modems the target parameters defined in the defining act.

5. A method for optimizing channel capacity in multi-tone communications effected across a plurality of subscriber lines by opposing sets of modems coupled thereto, and the method comprising:

obtaining the spectral characteristics of each of the plurality of subscriber lines from at least one of the opposing sets of modems;

defining target parameters including at least one of bit loading and power spectral density (PSD) for each tone of the multi-tone communications effected by the opposing sets of modems based on the spectral characteristics obtained in the obtaining act;

downloading to the at least one of the opposing sets of modems the target parameters defined in the defining act; and

further comprising at least one of the acts of;

quantifying interference on each tone for each of the plurality of subscriber lines from remaining ones of the plurality of subscriber lines;

determining which subscriber lines among the plurality of subscriber lines exhibit data rates exceeding a corresponding subscriber demand level; and

wherein the defining act further comprises defining the target parameters based on the spectral characteristics obtained in the obtaining act and at least one of the interference determined in the quantifying act and or the data rates determined in the determining act.

6. A means for optimizing channel capacity in multi-tone communications effected across a plurality of subscriber lines by opposing sets of modems coupled thereto, and the means comprising:

means for obtaining the spectral characteristics of each of the plurality of subscriber lines from at least one of the opposing sets of modems;

means for defining target parameters including at least one of hit loading and power spectral density (PSD) for each tone of the multi-tone communications effected by the opposing sets of modems based on the spectral characteristics obtained by the means for obtaining; and

wherein the means for defining further includes;

means for identifying relatively long and short subscriber lines within the plurality of subscriber lines from the spectral characteristics obtained by the means for obtaining; and

means for setting target parameters which effect a reduction in at least one of bit loading and PSD for high frequency tones in the relatively long subscriber lines identified by the means for identifying; and

means for downloading to the at least one of the opposing sets of modems the target parameters defined by the means for defining.

7. A means for optimizing channel capacity in multi-tone communications effected across a plurality of subscriber lines by opposing sets of modems coupled thereto, and the means comprising:

means for obtaining the spectral characteristics of each of the plurality of subscriber lines from at least one of the opposing sets of modems;

means for defining target parameters including at least one of bit loading and power spectral density (PSD) for each tone of the multi-tone communications effected by the opposing sets of modems based on the spectral characteristics obtained by the means for obtaining; and

wherein the means for defining further includes;

means for identifying underutilized tones with bit loading below a threshold value within the plurality of subscriber lines from the spectral characteristics obtained by the means for obtaining; and

means for setting target parameters which effect a reduction in at least one of bit loading and PSD for the underutilized tones identified by the means for identifying; and

means for downloading to the at least one of the opposing sets of modems the target parameters defined by the means for defining.