Remote Time Accuracy Measurement via Network Packet Analysis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing time synchronization systems require a GNSS antenna at the measurement location and sufficient advance GNSS signal reception, leading to complex environmental maintenance and human operation, making it difficult to measure in-device time accuracy.
Innovation Solution
A measurement instrument that acquires reference time from a satellite signal and calculates offsets between reference and in-device times using packet transmission and reception, allowing remote measurement of in-device time accuracy without the need for a GNSS antenna at the measurement location.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a GNSS antenna is installed at the measurement location to synchronize the measurement instrument with the GNSS, then the measurement instrument can accurately measure the in-device time accuracy, but the environmental maintenance becomes complex and requires preliminary preparation
Solution Approach 1:
The patent introduces a boundary clock as an intermediary device between the GNSS and the client device. The boundary clock receives GNSS signals and delivers synchronized time to the client device and measurement instrument via network packets, eliminating the need for direct GNSS antenna installation at the measurement location. This mediator approach resolves the contradiction by maintaining measurement precision while simplifying environmental setup.
Solution Approach 2:
The measurement instrument acquires copies of PTP packets transmitted between the boundary clock and client device. By analyzing these packet copies containing timestamp information, the instrument can calculate time offsets without requiring direct GNSS synchronization at its location. This copying mechanism enables accurate measurement while avoiding complex environmental maintenance.
2Measurement precision
If the measurement instrument is synchronized with the GNSS in advance, then it can perform accurate time measurements, but it requires sufficient advance GNSS signal reception and may lose synchronization during transport
Solution Approach 1:
The boundary clock serves as a continuous time reference intermediary that remains synchronized with GNSS at its fixed location. The measurement instrument obtains time reference information from the boundary clock via network packets rather than maintaining its own GNSS synchronization. This eliminates the need for advance synchronization and prevents synchronization loss during instrument transport.
Solution Approach 2:
The patent replaces the mechanical/physical GNSS antenna connection system with a network-based packet transmission system. Instead of requiring physical GNSS signal reception and maintaining continuous synchronization through transport, the system uses electronic packet exchange to deliver time reference information, eliminating synchronization maintenance time losses.
3Measurement precision
If the client device and measurement instrument are connected by a coaxial cable for 1PPS signal transmission, then the measurement can be performed, but the devices must be installed within the same building or close proximity
Solution Approach 1:
The patent replaces the physical coaxial cable connection system with a network-based packet transmission system. The measurement instrument receives time reference information and PTP packets through network communication rather than direct cable connections. This substitution enables remote measurement across different locations while maintaining measurement precision through digital packet analysis.
Solution Approach 2:
The invention transitions from a one-dimensional physical connection constraint (coaxial cable requiring close proximity) to a multi-dimensional network communication approach. By using network packets that can traverse various transmission media and distances, the system gains spatial flexibility while maintaining the ability to compare signal quality and measure time accuracy.
Data Source
AI summary
A measurement instrument (30) according to the present disclosure includes: a UTC acquisition unit (31) configured to acquire a reference time from a satellite signal; a BC time acquisition unit (32) configured to acquire time information regarding an in-device time of a first device (3); a UTC-BC offset calculation processing unit (33) configured to calculate a first offset that is a difference between the reference time and the in-device time of the first device (3) based on the reference time and the time information; a BC-client offset calculation processing unit (34) configured to acquire a copy of the packet and calculate a second offset that is a difference between the in-device time of the first device (3) and the in-device time of the second device (4) based on the acquired packet and a transmission delay between the first device (3) and the second device (4); and a time accuracy calculation processing unit (35) configured to measure accuracy of an in-device time of the second device (4) with respect to the reference time based on the first and second offsets.