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CN-122019273-A - Consistency voting method and device for multi-source time synchronization data

CN122019273ACN 122019273 ACN122019273 ACN 122019273ACN-122019273-A

Abstract

The invention discloses a consistency voting method and device of multisource time synchronization data, and relates to the technical field of high-reliability time synchronization of avionics, time-sensitive networks and the like. The method comprises the steps of collecting synchronous data containing local capturing time, original time deviation and accumulated frequency ratio from a plurality of independent clock sources respectively to obtain corresponding clock source data, carrying out validity screening on the clock source data, extrapolating the original time deviation of each effective clock source to set voting time based on the accumulated frequency ratio to obtain projection time deviation, determining an internal consistent trusted clock source subset through finite closure consistency verification based on all the projection time deviation, and calculating and outputting system time correction or performing degradation output according to verification results and redundancy conditions. The invention can eliminate false deviation caused by asynchronous sampling, realize deterministic fault isolation and fault tolerance voting, and ensure the safety and reliability of the system output under the scene of high safety requirements.

Inventors

  • SUN PENG

Assignees

  • 吉太航空科技(苏州)有限公司

Dates

Publication Date
20260512
Application Date
20260108

Claims (10)

  1. 1. A method of consistency voting of multi-source time synchronization data, comprising: Respectively acquiring time synchronization data from a plurality of independent clock sources to obtain corresponding clock source data, wherein the clock source data at least comprises local acquisition time, original time deviation and accumulated frequency ratio; Performing validity screening on each clock source data to obtain valid clock source data; Based on the accumulated frequency ratio of each effective clock source data, the original time deviation is extrapolated to the set voting moment to obtain the corresponding projection time deviation; Determining an internally consistent subset of trusted clock sources through a bounded closure consistency check based on all projected time deviations; And if the subset of the trusted clock sources is verified and converged and meets the preset redundancy condition, calculating and outputting the system time correction amount based on the projection time deviation of all the clock sources in the subset, otherwise, outputting the system time correction amount according to the preset degradation strategy.
  2. 2. The method for consistency voting of multi-source time synchronization data according to claim 1, the method is characterized in that the time synchronization data acquisition comprises the following steps: When a synchronous message from a clock source is received, a unique sampling identification is generated for the current acquisition, and the local acquisition time, the original time deviation and the accumulated frequency ratio obtained by the current acquisition are bound in an atomic operation mode so as to ensure that data originate from the same physical event.
  3. 3. The method of consistency voting of multi-source time synchronization data according to claim 1, wherein the validity screening comprises: And if the time difference between the voting time and the local capturing time does not exceed a preset maximum extrapolation window and the accumulated frequency ratio is in a preset trusted interval, judging that the corresponding clock source data is valid, otherwise, judging that the corresponding clock source data is invalid.
  4. 4. The method of consistency voting for multi-source time synchronization data according to claim 1, wherein the bounded closure consistency check comprises: Based on projection time bias of all effective clock sources, constructing a relation matrix representing whether any two clock sources are consistent, wherein the matrix is constructed only once in the voting period; Calculating the global support degree of each clock source according to the relation matrix, and selecting the clock source with the largest global support degree as a seed clock source; Constructing an initial candidate set by the seed clock source and other clock sources consistent with the seed clock source, and calculating the internal support degree of each member in the candidate set; Adding a member with the internal support less than the number of the members of the current candidate set minus one into a queue to be rechecked; and iteratively executing the rejection operation within the preset maximum rejection times: Taking out a clock source from the queue to be checked, if the internal support degree is less than the number of the current candidate set members by one, removing the clock source from the candidate set, and carrying out incremental update on the internal support degree of the rest members based on the relation matrix; And stopping iteration when the queue to be rechecked is empty, wherein the candidate set is the subset of the trusted clock source, judging that the verification is converged, and judging that the verification is not converged if the queue to be rechecked is still not empty when the maximum rejection number is reached.
  5. 5. The method for consistency voting of multi-source time synchronization data according to claim 4, wherein when the relation matrix is constructed, if the absolute value of the difference between the projection time deviations of the two clock sources is smaller than a preset consistency threshold, the two clock sources are judged to be consistent; Wherein the consistency threshold is not less than an upper bound of a measurement noise estimate based on a time synchronization protocol or a measurement noise floor obtained by offline calibration.
  6. 6. The method of claim 4, wherein in the bounded closure consistency check, a first-in first-out queue is used to manage the clock sources to be checked and a status flag is set for each clock source to ensure that it is processed at most once in a voting period.
  7. 7. The method for coherent voting of multi-source time synchronization data according to claim 4, wherein when the global support of the plurality of clock sources is the same as the maximum value, the clock source with the smallest channel number is selected as the seed clock source.
  8. 8. The method for consistency voting of multi-source time synchronization data according to claim 1, wherein the system time correction is calculated and output based on the subset of trusted clock sources by means of weighted averaging of projected time deviations of the respective clock sources within the subset of trusted clock sources; wherein the weights are configured to be equal weights or indicators of measured quality based on the history of each clock source.
  9. 9. The method of consistent voting of multi-source time synchronization data according to claim 1, wherein the downgrading strategy comprises: and multiplexing the system time correction amount output in the last effective voting period or outputting the correction amount calculated based on the preset guaranteed-bottom clock source.
  10. 10. A computer apparatus, comprising: A memory for storing computer programs/instructions; a processor for executing the computer program/instructions to implement the steps of the method for consistency voting of multi-source time synchronization data according to any one of claims 1 to 9.

Description

Consistency voting method and device for multi-source time synchronization data Technical Field The invention relates to a consistency voting method and device for multisource time synchronization data, and belongs to the technical field of high-reliability time synchronization of avionics, time-sensitive networks and the like. Background In high security level systems such as avionics, autopilot controllers, etc., terminal devices typically employ a multimode redundancy architecture while tracking three or more independent master clock sources in order to meet high reliability requirements. The fault-tolerant time service management entity in the terminal equipment needs to monitor the health states of the clock sources in real time, identify and reject fault sources through a consistency voting algorithm, and calculate the optimal system time, and the prior art has the defects that when multi-source redundancy voting is implemented, time domains of asynchronous sampling are not aligned, for example, the time domains of the asynchronous sampling are influenced by network queuing delay and protocol stack scheduling jitter, and the arrival time of data of different clock sources is discrete. The data collected at different times are directly compared transversely, and false errors caused by local clock drift can be introduced. Existing methods often lack stringent constraints on the "freshness" of the sampled data. If some channel data is not updated for a long time, the old data is directly used for holding or extrapolation, and accumulated errors are amplified with the lapse of time. The existing standard only focuses on the calibration of a single link, and does not 'normalize' multiple paths of asynchronously acquired data to the same physical moment for fair comparison. Disclosure of Invention The invention aims to provide a consistency voting method and device for multi-source time synchronous data, which are used for eliminating deviation introduced by local clock drift by projecting multi-path asynchronously-arrived clock source data to unified voting time, realizing fault isolation and voting by combining double validity screening and adopting closure consistency check, and ensuring the safety and reliability of system output. In order to achieve the above purpose, the invention is realized by adopting the following technical scheme. In one aspect, the invention provides a method for consistency voting of multi-source time synchronization data, comprising the following steps: Respectively acquiring time synchronization data from a plurality of independent clock sources to obtain corresponding clock source data, wherein the clock source data at least comprises local acquisition time, original time deviation and accumulated frequency ratio; Performing validity screening on each clock source data to obtain valid clock source data; Based on the accumulated frequency ratio of each effective clock source data, the original time deviation is extrapolated to the set voting moment to obtain the corresponding projection time deviation; Determining an internally consistent subset of trusted clock sources through a bounded closure consistency check based on all projected time deviations; And if the subset of the trusted clock sources is verified and converged and meets the preset redundancy condition, calculating and outputting the system time correction amount based on the projection time deviation of all the clock sources in the subset, otherwise, outputting the system time correction amount according to the preset degradation strategy. Optionally, the collecting time synchronization data includes: When a synchronous message from a clock source is received, a unique sampling identification is generated for the current acquisition, and the local acquisition time, the original time deviation and the accumulated frequency ratio obtained by the current acquisition are bound in an atomic operation mode so as to ensure that data originate from the same physical event. Optionally, the validity screening includes: And if the time difference between the voting time and the local capturing time does not exceed a preset maximum extrapolation window and the accumulated frequency ratio is in a preset trusted interval, judging that the corresponding clock source data is valid, otherwise, judging that the corresponding clock source data is invalid. Optionally, the bounded closure consistency check includes: Based on projection time bias of all effective clock sources, constructing a relation matrix representing whether any two clock sources are consistent, wherein the matrix is constructed only once in the voting period; Calculating the global support degree of each clock source according to the relation matrix, and selecting the clock source with the largest global support degree as a seed clock source; Constructing an initial candidate set by the seed clock source and other clock sources consistent with the seed clock sou