Patent ID: 11927923
Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
Field: Measurement (Instruments)
Classification: CPC G  H | IPC G

Claim 4:
5. A time synchronization method in a management apparatus of a time synchronization system including a plurality of time synchronization apparatuses, each of the plurality of time synchronization apparatuses being configured to receive a radio wave from a positioning satellite and to take time synchronization using time information included in the received radio wave as a time source to deliver a time, the method comprising:
acquiring time variation information and position information of each of the time synchronization apparatuses;
classifying the time synchronization apparatuses into predetermined categories based on the acquired position information;
determining a first subset of time synchronization apparatuses of the plurality of time synchronization apparatuses based on whether patterns of the time variation information of each time synchronization apparatuses belonging to an identical category are identical to each other;
analyzing the time variation information based on the first subset of time synchronization apparatuses; and
outputting an instruction to block the time variation information received from the positioning satellite, to the time synchronization apparatus having abnormal time variation.