Phase Rotation Feedback for DSL Crosstalk Mitigation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In DSL systems, strong crosstalk between twisted pair lines leads to a low signal-to-noise ratio, making it difficult for customer-premises equipment to maintain synchronization and effectively eliminate far-end crosstalk, resulting in poor signal quality.
Innovation Solution
The method involves rotating the phases of signals on one line set relative to another to mitigate crosstalk, with the network side device sequentially rotating phases of to-be-sent signals and using feedback from high-quality received signals to adjust subsequent signal phases, ensuring high signal-to-noise ratios during transmission.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If vectored DSL technology is used to eliminate far-end crosstalk, then crosstalk elimination capability is improved, but signal-to-noise ratio deteriorates due to synchronization failure
Solution Approach 1:
The patent implements a feedback mechanism where the user side detects the quality of received signals and feeds back quality information to the network side. The network side uses this feedback to adjust signal parameters, creating a closed-loop system that adapts to changing channel conditions and maintains signal quality despite crosstalk
Solution Approach 2:
The patent dynamically adjusts signal transmission parameters based on real-time channel conditions. The network side changes signal characteristics such as phase rotation angles according to feedback information, transforming a static transmission system into a dynamic one that adapts to varying crosstalk and noise conditions
2Device complexity
If synchronous sending and receiving is used, then signal processing simplicity is improved, but synchronization maintenance deteriorates in strong crosstalk scenarios
Solution Approach 1:
The feedback mechanism allows the system to detect synchronization status and quality degradation, enabling adaptive adjustments that maintain effective synchronization without requiring complex predetermined synchronization protocols
Solution Approach 2:
The patent changes signal parameters such as phase rotation angles based on feedback information to compensate for synchronization issues caused by crosstalk, maintaining signal quality without requiring perfect synchronous operation
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach maintains relatively high signal quality even in environments with strong crosstalk by selecting and processing high-quality signals, enhancing data transmission reliability and accuracy.
Implementation Method 1
rotating phases of to-be-sent signals on a line set 1 by different angles and in relative to phases of to-be-sent signals on a line set 2
Implementation Method 2
Due to an electromagnetic induction principle, mutual crosstalk occurs between signals on the multiple DSL lines that access the network side
Data Source
AI summary
Embodiments of the present invention provide a signal transmission method. The method includes: sequentially rotating phases of to-be-sent signals on a line set 1 by different angles and in relative to phases of to-be-sent signals on a line set 2, and sequentially sending, to a user side, the to-be-sent signals whose phases are rotated. The method also includes receiving a rotation factor that is of a high-quality received signal on the line set 1 and that is fed back by the user side, where the high-quality received signal includes a received signal with a high signal-to-noise ratio or high power. The method also includes using the rotation factor fed back by the user side as a fixed rotation factor, and rotating, according to the fixed rotation factor, a phase of a signal to be subsequently sent on the line set 1.