| 摘要 |
PURPOSE:To prevent the reduction in efficiency of a data link by revising only a position information file of a group subscriber attended with the movement of a mobile body. CONSTITUTION:An in-mobile body file 15 and an area code comparison section 14 are provided in the inside of a mobile body (b) and ID number and telephone number of a portable terminal equipment of subscribers (c), (d) ridden in the mobile body are described in the file 15. When the mobile body (b) moves from an area B to an area A, the change into the area A from the area B is described to a data base of the mobile body (b) as location information of the mobile body (b). Thus, in obtaining the location information of the subscriber (c), the storage destination of the data base of the mobile body (b) is obtained from the data base of the subscriber (c), it is read out to recognize the position of the mobile body to call the subscriber (c). Thus, even if the area of the mobile body (b) changes, only the position information of the mobile body (b) is revised. |
