US 12,177,807 B2
Interface conversion device, control circuit, storage medium, and anomaly detection method
Masao Oga, Tokyo (JP); Keijiro Take, Tokyo (JP); and Ryo Matsunaga, Tokyo (JP)
Assigned to MITSUBISHI ELECTRIC CORPORATION, Tokyo (JP)
Filed by Mitsubishi Electric Corporation, Tokyo (JP)
Filed on Jun. 15, 2022, as Appl. No. 17/841,340.
Application 17/841,340 is a continuation of application No. PCT/JP2020/007183, filed on Feb. 21, 2020.
Prior Publication US 2022/0312358 A1, Sep. 29, 2022
Int. Cl. H04W 56/00 (2009.01); H04W 92/18 (2009.01)
CPC H04W 56/0065 (2013.01) [H04W 56/001 (2013.01); H04W 92/18 (2013.01)] 8 Claims
OG exemplary drawing
 
1. An interface conversion device of a mobile communication system to transmit an industrial protocol, the device comprising:
delay amount measurement circuitry to measure a delay amount inside the mobile communication system from a difference between an input time at which the mobile communication system has acquired a periodically transmitted time-synchronization signal and an output time at which the mobile communication system outputs the time-synchronization signal, the input time being included in the time-synchronization signal;
storage circuitry to store delay amount history information including a delay amount measurement value measured by the delay amount measurement circuitry;
variation evaluation circuitry to measure a variation amount indicating an instantaneous variation of the delay amount by acquiring a delay amount reference value from the delay amount history information and measuring a variation amount of a delay amount measurement value from a difference between the delay mount reference value and the measured delay amount inside the mobile communication system and to evaluate whether the variation amount is within an allowable range; and
anomaly detection circuitry to detect a communication anomaly in the mobile communication system on a basis of an evaluation result provided by the variation evaluation circuitry.