| 摘要 |
PROBLEM TO BE SOLVED: To provide a group communication system wherein a system does not stop when a trouble is generated in a parent apparatus. SOLUTION: PHS terminal equipments 1a, 1b, etc., send data of gas meters 2a, 2b, etc., to a switching office 4 via repeaters 3a, 3b, etc., The switching office 4 sends the data to a data collecting center 11 via an ISDN circuit 9. The part between the terminal equipment 1 and the repeater 3 is a wireless private network, and the part between the repeater 3 and the switching office 4 is a wireless public network. The switching office 4 is a base station of a PHS system. That is, the repeater 3 is connected with the public network and the number of the repeaters is much smaller than that of the terminal equipments, so that communication charge is reduced. One terminal equipment 1 can be connected with two or more repeaters 3, so that data communication is not obstructed when one repeater goes out of order. |
