DSL Receiver Crosstalk Decorrelation Using Cross-Correlated Noise
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Digital Subscriber Line (DSL) systems face interference issues due to crosstalk, which reduces signal-to-noise ratios and affects data transmission quality, particularly in multi-pair systems where signals from one twisted-pair inductively couple with others, leading to Far-End-Crosstalk (FEXT) and Near-End-Crosstalk (NEXT).
Innovation Solution
A receiver-coordinated system that includes error estimators and noise predictors to estimate and decorrelate noise across multiple twisted-pair lines, using cross-correlation values to predict and mitigate crosstalk interference, thereby improving signal quality and reducing noise levels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If multi-pair DSL systems are implemented to increase data transmission capacity, then productivity is improved, but crosstalk interference increases causing signal-to-noise ratio degradation
Solution Approach 1:
The patent estimates crosstalk noise affecting each line and uses this harmful interference information to generate compensation signals. By applying these compensation signals through the decorrelation component, the previously harmful crosstalk is converted into a beneficial cancellation mechanism, thereby improving signal quality while maintaining multi-pair transmission capacity
Solution Approach 2:
The patent introduces an intermediary processing mechanism between the received signal and the decoded signal. The error estimator and noise predictor act as intermediaries that analyze the received signal, estimate crosstalk components, and generate compensation signals. This intermediary processing layer enables the system to mitigate crosstalk interference without requiring fundamental changes to the multi-pair transmission architecture
2Reliability
If noise estimation and decorrelation processing is applied to reduce crosstalk, then signal-to-noise ratio is improved, but device complexity increases
Solution Approach 1:
The patent segments the noise reduction task into distinct functional components: an error estimator that processes each line independently to generate error estimates, a noise predictor that calculates cross-correlation values between lines, and a decorrelation component that applies compensation signals. This segmentation allows each component to perform a specific function efficiently, reducing overall processing complexity while achieving effective crosstalk mitigation
Solution Approach 2:
The system uses the received signal itself and the decoded signal to generate error estimates that form the basis for noise prediction and compensation. The error between received and decoded signals is leveraged as a self-generated reference for estimating crosstalk interference, eliminating the need for external calibration signals or additional training sequences, thereby reducing system complexity
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
The system effectively decorrelates noise across multiple lines, enhancing data bandwidth and signal quality by reducing crosstalk interference, allowing for increased data transmission rates and improved signal-to-noise ratios.
Implementation Method 1
A noise predictor applies a predetermined cross-correlation value, which describes noise cross-correlation between the first line and a second line
Implementation Method 2
A noise predictor applies a predetermined cross-correlation value, which describes noise cross-correlation between the first line and a second line of the plurality of lines, to the error estimate to provide an estimate for correlated noise term in the second line
Implementation Method 3
A noise decorrelation component applies the cross-correlated noise term to substantially decorrelate noise for the second line
Implementation Method 4
when a signal from one copper pair inductively couples with the signal in another pair
Data Source
AI summary
Systems and methods are disclosed for determining mitigating noise in multi-pair communication system. A receiver coordinated system can include an error estimator that estimates noise for a first line of a plurality lines and provides an error estimate for the first line. A noise predictor applies a predetermined cross-correlation value to the error estimate to provide a correlated noise term that describes noise cross-correlation between the first line and a second line of the plurality of lines. A noise decorrelation component applies the cross-correlated noise term to substantially decorrelate noise for the second line.