Vehicle Time Synchronization With Corrected Transmission Timing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing vehicle-mounted communication systems face operation abnormalities due to fluctuations in the reference time transmitted by the grandmaster, leading to discrepancies in data storage times and inconsistent operation among connected apparatuses.
Innovation Solution
A vehicle-mounted apparatus that corrects the transmission time of synchronization information based on the time difference between current and previous transmission times, using a correction unit to adjust the transmission time by adding the transmission cycle and a split time difference, ensuring consistent time synchronization and data storage across the system.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the grandmaster transmits reference time on the network, then time synchronization is achieved, but operation abnormalities occur due to fluctuations in the reference time
Solution Approach 1:
The system calculates the time difference between the current time and the previous transmission time, then feeds back this difference to correct the transmission time in the current transmission process. This feedback mechanism compensates for reference time fluctuations by continuously adjusting the transmission time based on observed deviations, thereby maintaining stable time synchronization despite grandmaster clock variations.
Solution Approach 2:
The invention dynamically changes the transmission time parameter by adding a correction value derived from the time difference calculation. Instead of using a fixed transmission time, the system adjusts this parameter in real-time based on the calculated deviation, allowing the synchronization system to adapt to reference time fluctuations and maintain operational reliability.
2Productivity
If time synchronization information is transmitted at a predetermined cycle, then synchronization is maintained, but data storage time discrepancies occur due to reference time fluctuations
Solution Approach 1:
The system dynamically adjusts the transmission time parameter by incorporating a correction value calculated from the time difference between current and previous transmission times. This parameter change ensures that even though transmissions occur at predetermined cycles, the actual transmission times are corrected to maintain consistent data storage timing across all connected apparatuses, preventing time discrepancy accumulation.
Solution Approach 2:
The correction value is calculated in advance based on the time difference before the current transmission occurs. By performing this preliminary calculation and adjustment, the system proactively compensates for potential time discrepancies that would otherwise accumulate during regular transmission cycles, ensuring data storage time consistency is maintained from the outset.
Data Source
AI summary
A vehicle-mounted apparatus includes: a transmission processing unit configured to perform a transmission process for transmitting, to another vehicle-mounted apparatus, first time synchronization information and second time synchronization information that includes a transmission time at which the first time synchronization information is transmitted, at a predetermined transmission cycle; and a correction unit configured to perform a correction process for correcting the transmission time to be included in the second time synchronization information in a current transmission process, based on a time difference between a current time at the vehicle-mounted apparatus and a previous transmission time, the previous transmission time being the transmission time in the previous transmission process, to a corrected transmission time obtained by adding, to the previous transmission time, the transmission cycle and a value obtained by splitting the time difference.