Communication system, abnormality detection device and abnormality detection method

An abnormality detection device detecting abnormality concerning communication, in a communication system comprising a plurality of communication devices connected to each other via a common communication line to transmit and receive binary information through the communication line, each of the communication devices including a reception part receiving information by sampling voltage of the communication line once at a predetermined timing during a transmission period of one-bit information, and the plurality of communication devices being allowed to perform sampling at different timings, the abnormality detection device being connected to the communication line, and comprising:

• a sampling part sampling voltage of the communication line a plurality of times over a predetermined period including a timing of earliest sampling and a timing of latest timing in sampling performed by the plurality of communication devices, wherein the predetermined period is shorter than the transmission period of one-bit information:
• and
• a detection part detecting abnormality concerning communication based on a plurality of sampling results obtained by the sampling part, wherein an abnormality is determined if a sampling result of sampling performed by the sampling part is different from a previous sampling result.

An abnormality detection method detecting abnormality concerning communication, in a communication system comprising a plurality of communication devices connected to each other via a common communication line to transmit and receive binary information through the communication line, each of the communication devices including a reception part receiving information by sampling voltage of the communication line once at a predetermined timing during a transmission period of one-bit information, and the plurality of communication devices being allowed to perform sampling at different timings,

• sampling voltage of the communication line a plurality of times over a predetermined period including a timing of the earliest sampling and a timing of the latest timing in the sampling performed by the plurality of communication devices, wherein the predetermined period is shorter than the transmission period of one-bit information:
• and
• detecting abnormality concerning communication based on the plurality of sampling results, wherein an abnormality is determined if a sampling result of sampling performed by the sampling part is different from a previous sampling result.