| 摘要 |
PROBLEM TO BE SOLVED: To avoid occurrence of a situation in which a terminal on a vehicle and a host device outside the vehicle cannot communicate with each other when necessary, without installing a dedicated relay device even in a case where a radio communication device only capable of communication in a relatively narrow area is used.SOLUTION: An on-vehicle data communication device comprises: a wireless communication unit 207 which has an infrastructure communication mode and an ad-hoc communication mode; and a communication control unit 201 which automatically switches the infrastructure communication mode and the ad-hoc communication mode of the wireless communication unit according to the situation when data transmission is necessary, has the wireless communication unit directly transmit data to a management device 100 when the infrastructure communication mode has been selected, and has the wireless communication unit transmit data to the management device 100 via another terminal as a relay station when the ad-hoc communication mode has been selected. |
