Patent ID: 8626833
Filing Date: 2014-01-07
Classification: H04L

Abstract:
1. A communication system to be mounted on a car having a communication network in which a plurality of terminals is connected to a common bus, a plurality of electronic control units is connected to one another via said bus, and messages are sent among said electronic control units at predetermined transmission intervals and said sent messages are received thereby, wherein said messages sent and received among said electronic control units via said bus are divided into a plurality of groups such as a first group, a second group, . . . and an Nth group in dependence on a kind of message information; each of said electronic control units has a transmission timing operation part computing transmission timings of messages of each group to be sent; and said transmission timing operation part decreases a difference between (i) transmission timings of messages, belonging to the same group, which are to be sent from one of said electronic control units and (ii) transmission timings of messages, belonging to the same group, which are received from said other electronic control units; said parent message and said child messages are not set in each group; said transmission timing operation part adjusts transmission timings of messages so that the difference between transmission timings of messages, belonging to the same group, which are to be sent from one of said electronic control units and transmission timings of all messages, belonging to the same group, which are received from said other electronic control units is decreased; and said transmission timing operation part adjusts transmission timings of messages so that a difference between said transmission timings of said messages belonging to said other groups is increased.