| 摘要 |
It is expected to provide a communication apparatus, relay apparatus, communication system and communication method for effectively performing a communication timing adjustment when a collision has occurred on a communication line, efficiently reducing the communication collision with reducing processing loads on each apparatus, for making each apparatus effectively perform the transmission timing adjustment, and for improving the communication efficiency. ECUs are connected to communication lines with a bus topology. A relay apparatus is connected to the communication lines, obtains a time distribution based on a number of messages transmitted to the communication lines. When the bias occurs in the transmission timings, the relay apparatus transmits an instruction message that instructs to perform the timing adjustment for messages transmitted between the ECUs. In addition, it is determined whether a message to be relayed is held. When it is determined that such a message is held, the instruction message is transmitted. |
