DSL Crosstalk Mitigation via Time Division Scheduling

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Solution Overview

Problem

High-speed data transmission over DSL networks is hindered by electrical crosstalk, which causes signal degradation and reduces communication speed due to the constant activity of DSL lines and lack of coordination in data transmissions.

Innovation Solution

Implementing time division multiplexing (TDM) in the electrical network to schedule data transmissions, disallowing overlapping data transmissions on lines with high cross-talk values, thereby reducing crosstalk and simplifying the transfer matrix, and using an optical management node to transmit schedule information and cross-talk cancellation matrices.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of operation

If DSL lines are kept constantly active to maintain network availability, then network accessibility is improved, but electrical crosstalk increases causing signal degradation

Engineering Contradiction:
Improvenetwork accessibilityVSAvoidelectrical crosstalk
Core Design Contradiction:
Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The patent implements time-division multiplexing where DSL lines are activated in periodic time slots rather than continuously. Each line transmits data during its assigned time window and remains inactive during other lines' transmission periods, creating a periodic on-off pattern that eliminates simultaneous transmissions and reduces crosstalk while maintaining network availability.

Inventive Principle:
Principle #19Periodic action

2Productivity

If multiple data transmissions occur simultaneously on different DSL lines, then communication throughput is improved, but signal degradation due to crosstalk increases

Engineering Contradiction:
Improvecommunication throughputVSAvoidsignal quality
Core Design Contradiction:
ProductivityVSReliability

Solution Approach 1:

The patent segments the transmission medium into multiple time slots, assigning each DSL line to a specific time window. This temporal segmentation prevents overlapping transmissions on lines with high crosstalk coupling, ensuring signal quality while still achieving high throughput through parallel transmissions in different time slots.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The system dynamically adjusts the transmission schedule based on calculated crosstalk values between line pairs. Lines with high mutual crosstalk are assigned non-overlapping time slots, while lines with low crosstalk may transmit simultaneously. This dynamic scheduling optimizes both throughput and signal quality based on the electrical characteristics of the network.

Inventive Principle:
Principle #15Dynamics

3Reliability

If time division multiplexing is implemented to reduce crosstalk, then signal quality is improved, but transmission coordination complexity increases

Engineering Contradiction:
Improvesignal qualityVSAvoidtransmission coordination
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The system calculates crosstalk values between all line pairs and uses this information to automatically generate optimal transmission schedules. The coordination complexity is managed through algorithmic self-configuration rather than manual setup, allowing the system to adapt to changing network conditions while maintaining signal quality through automated schedule optimization.

Inventive Principle:
Principle #25Self-service

Data Source

PatentEP2912775B1Data transmission coordination over digital subscriber lines
Publication Date: 2017.09.13 HUAWEI TECH CO LTD
  • EP2912775B1 patent drawingFigure 1
  • EP2912775B1 patent drawingFigure 2
  • EP2912775B1 patent drawingFigure 3

AI summary

An optical management node comprising a memory comprising instructions, a processor coupled to the memory and configured execute the instructions, wherein executing the instructions causes the processor to schedule data transmissions across an electrical network between a plurality of user terminals and an optoelectrical interface by using time division multiplexing or time division multiple access based on optimization of crosstalk performance of electrical lines of the electrical network, and a transmitter coupled to the processor and configured to transmit schedule information to the optoelectrical interface via an optical network. Also disclosed is a method implemented in a management node comprising scheduling data transmissions with a plurality of user terminals across a Digital Subscriber Line (DSL) network using time division scheduling based on optimization of crosstalk performance of DSL lines of the DSL network, and transmitting schedule information to the user terminals via an optical network.