Vectored DSL Vector Coefficient Training via Pilot Estimation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current Vector coefficient training methods for vectored digital subscriber lines are inefficient, particularly when a new line is added, requiring extensive time and multiple coefficient estimations, which negatively impacts user experience and system activation speed.
Innovation Solution
The method involves calculating initial precoding and cancellation coefficients using a pilot estimation method after a handshake phase and compensating them with power or phase adjustment factors during channel discovery and training phases, and acquiring historical coefficients to update interference representations between lines, thereby reducing the need for repeated calculations and shortening the training process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If multiple coefficient estimations are performed using regular estimation methods, then coefficient accuracy is improved, but training time increases significantly
Solution Approach 1:
The patent performs preliminary coefficient estimation during the handshake phase between DSLAM and CPE, before the channel discovery phase. These preliminary coefficients are then used during subsequent phases, eliminating the need for repeated full estimations and significantly reducing training time while maintaining acceptable accuracy
Solution Approach 2:
The patent changes the estimation parameters and methods dynamically across different phases. During handshake phase, full pilot sequence estimation is performed. During channel discovery and training phases, the patent uses compensated coefficients with adjustment factors, changing the estimation approach to reduce computational overhead while maintaining performance
2Adaptability or versatility
If a new line is added to the system, then system capacity is improved, but activation time increases due to re-estimation requirements
Solution Approach 1:
When a new line is added, the system performs preliminary coefficient estimation during the handshake phase between the DSLAM and CPE. These coefficients are prepared in advance and used during channel discovery and training phases, enabling rapid activation without requiring multiple sequential re-estimations
Solution Approach 2:
The patent implements feedback mechanisms where coefficients estimated during the handshake phase are used as initial values for subsequent phases. The system continuously adjusts and compensates these coefficients based on signal power and phase changes detected during channel discovery and training, creating an iterative feedback loop that reduces activation time
3Measurement precision
If multiple coefficient estimations are performed for interference representation, then interference cancellation accuracy is improved, but processing complexity increases
Solution Approach 1:
The patent performs preliminary estimation of interference coefficients during the handshake phase, before channel discovery and training phases. These pre-computed coefficients reduce the processing complexity during subsequent phases by eliminating the need for repeated full estimations while maintaining interference cancellation accuracy
Solution Approach 2:
The patent changes the estimation approach based on system phase. During handshake phase, full pilot sequence estimation is performed for accurate interference representation. During channel discovery and training phases, the patent uses compensated coefficients with adjustment factors, changing the processing method to reduce complexity while maintaining performance
Data Source
AI summary
The present invention provides a method and an apparatus for training a Vector coefficient of a vectored digital subscriber line, where the method includes: after a handshake phase is executed for a joining line, calculating, by using a pilot estimation method, an initial precoding coefficient and an initial cancellation coefficient that represent interference from the joining line to a normal working line; and after a channel discovery phase is executed for the joining line, compensating the initial precoding coefficient and the initial cancellation coefficient by using a compensation factor, to obtain a precoding coefficient and a cancellation coefficient that represent the interference from the joining line to the normal working line, wherein the compensation factor is obtained according to a signal power change or a signal phase change of the joining line. The present invention improves efficiency of Vector coefficient training.