DSL Data-Flow Quality Control via Dynamic Bit Allocation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In Digital Subscriber Line (DSL) communications systems, existing bit swap mechanisms are inadequate for rapidly changing noise conditions, leading to instability and potential data corruption due to limited ability to adjust bit allocations quickly enough, especially in high-noise environments.
Innovation Solution
A method where the transmitter decreases the bit allocation uniformly across multiple data carriers in response to unsatisfactory data flow quality, improving noise margin without complex calculations, allowing for rapid stabilization of modem behavior and reducing corrupt frame transmission probabilities.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional bit swap mechanism is used to adjust bit allocation, then data-flow quality can be improved, but the adjustment speed is too slow to keep up with rapidly changing noise conditions
Solution Approach 1:
The patent changes the adjustment step size dynamically based on signal quality conditions. When signal quality deteriorates rapidly, larger bit swap steps are applied to achieve faster convergence. This allows the system to adapt the speed of parameter adjustment according to the urgency of the situation, resolving the contradiction between reliable quality improvement and fast response speed.
Solution Approach 2:
The bit swap mechanism transitions from static fixed-step adjustment to dynamic adaptive-step adjustment. The system continuously monitors signal quality and modifies the bit swap step size in real-time, making the adjustment process dynamic rather than rigid. This enables faster response to rapidly changing noise conditions while maintaining stability when conditions are favorable.
2Adaptability or versatility
If larger bit swap requests are used to include all carriers, then more carriers can be adjusted, but the probability of message corruption increases in high-noise environments
Solution Approach 1:
The patent segments the bit swap process into multiple smaller steps rather than attempting to adjust all carriers in a single large request. This segmentation reduces the size of individual control messages, lowering their corruption probability in high-noise environments. The cumulative effect of multiple small adjustments achieves the same overall adaptation as a single large adjustment would provide.
Solution Approach 2:
Instead of performing a complete bit swap across all carriers in one step, the patent applies partial adjustments in iterative stages. Each stage adjusts a subset of carriers or applies a partial bit reallocation, reducing message complexity and corruption risk. The process continues iteratively until the desired adaptation is achieved, balancing message reliability with comprehensive carrier adjustment.
3Reliability
If bit allocation is decreased uniformly across multiple carriers, then noise margin improves quickly, but data transmission rate is reduced
Solution Approach 1:
The patent dynamically changes the bit allocation parameters based on monitored signal quality. When noise conditions improve or stabilize, the system increases bit allocation to restore higher data rates. When noise deteriorates, bit allocation is decreased to maintain stability. This dynamic parameter adjustment resolves the contradiction by adapting the transmission rate to current channel conditions rather than maintaining a fixed conservative rate.
Solution Approach 2:
The system implements feedback monitoring of signal quality metrics and uses this information to adjust bit allocation decisions. The feedback loop allows the system to learn from past adjustments and optimize the balance between stability and transmission rate. When the system detects that stability has been achieved, it can safely increase the data rate, thus resolving the contradiction through informed decision-making based on actual system performance.
Data Source
AI summary
The present invention relates to a method for data-flow quality control in a Digital Subscriber Line communications system comprising a transmitter, a receiver, and a Digital Subscriber Line intercoupling the transmitter and the receiver. The transmitter sends a data-flow to the receiver, where the data-flow is modulated onto data-carriers according to a bit allocation indicative for the number of bits to be modulated on each data-carrier. The method comprises the steps of the receiver measuring the data-flow quality and subsequently the receiver instructs the transmitter to decrease the bit allocation with a same amount for a plurality of data-carriers in case the data-flow quality is unsatisfactorily low. Then the transmitter decreases the bit allocation accordingly.