| 摘要 |
PROBLEM TO BE SOLVED: To report positional information to a vehicle which is not equipped with a car navigation device. SOLUTION: A mobile communication system to which the car navigation system is applied is provided with a portable telephone 1 mounted on an automobile 71, a portable telephone 2 mounted on an automobile 72, the car navigation device 3 connected to the portable telephone 2, a base station 41 and a base station 42 which are connected to a mobile data communication-serviceable public mobile communication network (PLMN) 5 and a positional information center 6 which is connected to the PLMN 5, which receives a request for positional information on the portable telephone 1 from the portable telephone 2 and which reports the positional information on the portable telephone 1 to the car navigation device 3 via the portable telephone 2 after the positional information on the portable telephone 1 has been searched. |
