| 摘要 |
PURPOSE:To rapidly set up a line for urgent communication by using an idle reservation line for a communication line when there is no idle line because all communication lines are temporarily being used. CONSTITUTION:When reservation receiving capacity exceeds a prescribed value or no idle line state is continued for a fixed time, a reference station G informs the urgent state to respective earth stations A to F through control lines. Respective earth stations A to F use part of a reservation slot as a subdata slot in common and at random. The reference station G successively allocates the sub-data slot to the reserved earth stations (e.g. E, F) and the allocated earth stations E, F execute communication for one subdata slot independently of data volume owned by respective earth stations E, F. When an idle data slot is formed in the urgent state, allocation is successively executed, and when the number of reserved stations is reduced less than a fixed value or to zero, the urgent state is released. Thereby, urgent communication and the communication of small data can be executed, the disconnected time of each earth station can be reduced and the efficiency of lines can be improved. |
