Clock Signal Synchronization Using Delay-Weighted Message Filtering
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for synchronizing clock signals in data networks face challenges due to random transmission delays, particularly in heavily loaded networks, which complicate the adjustment process and weaken the quality of synchronization between clock signals.
Innovation Solution
A system that calculates a synchronizing message difference value based on the reception and transmission times of synchronizing messages, with an adjusting mechanism that weights information from chronologically successive messages to adjust the clock signal, focusing on the least interfered part of the information to maintain synchronization regardless of network load.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If the observation period is extended to decrease the share of random-type element in transmission delay, then the measurement precision of transmission delay is improved, but the adjusting process becomes more complex and the synchronization quality weakens due to extended chronological interval between successive adjusting measures
Solution Approach 1:
The patent extracts only the useful portion of synchronizing messages by selecting those with the shortest transmission delay, excluding messages affected by random queuing delays. This extraction principle allows the system to use a shorter observation period while maintaining measurement precision, thereby avoiding the complexity and synchronization degradation that would result from extending the observation period.
2Productivity
If synchronizing messages are used for adjusting clock signal in heavily loaded networks, then the productivity of clock synchronization is maintained, but the measurement precision of transmission delay deteriorates due to random-type queuing delays
Solution Approach 1:
The patent applies local quality by treating different synchronizing messages differently based on their transmission delay characteristics. Messages with the shortest transmission delay are selected for adjustment, while messages with longer delays (affected by queuing) are excluded. This selective approach maintains productivity by continuously processing available synchronizing messages while ensuring measurement precision through quality-based selection.
Solution Approach 2:
The system uses feedback by continuously monitoring transmission delays of synchronizing messages and dynamically selecting those with the shortest delay for clock adjustment. This feedback mechanism allows the system to adapt to varying network load conditions, maintaining both productivity and measurement precision by automatically adjusting which messages are used based on real-time delay measurements.
Data Source
AI summary
The invention relates to a method and system for adjusting a clock signal placed in a network element of a data network. The clock signal is adjusted on the basis of difference values formed by means of received synchronizing messages. Each difference value is a difference of a reception time value and a transmission value of a received synchronizing message. The reception time value of the synchronizing message depends on a cumulated number of periods of the clock signal at a moment of arrival of the synchronizing message, and the transmission value depends on a position of the synchronizing message in a chronological transmission order of the synchronizing messages. In the adjusting process, an adjusting effect of the difference values belonging to a lower part (304) of a margin of fluctuation (306) of the difference values is weighted more heavily than an adjusting effect of the difference values belonging to an upper part (305) of the margin of fluctuation of the difference values. Thus, for adjusting the clock signal, there can be used that share of information represented by the received synchronizing messages that has the least interference, irrespective of the load situation of the data network.