| 摘要 |
PURPOSE:To previously give an alarm before a zone is changed when the channel of a channel switching destination radio base station is full blocked on the channel busy alarm system of moving radio communication. CONSTITUTION:A level judgement means 4 is provided for a moving machine terminal 3, and a radio communication level with an adjacent radio base station 11 is judged. If a value reaches a channel switching start level for the adjacent radio base station 12 as the result of level judgement when the moving machine terminal 3 moves from the zone of the radio base station 11 to the zone of the adjacent radio base station 12, the channel use situation inquiry of the adjacent radio base station 12 is transmitted from the moving machine terminal 3 to a radio control station 2 through the former radio base station 11. Furthermore, a use situation judgement means 5 is provided for the radio control station 2, the channel idle/block situation of the respective radio base stations 11, 12,... is judged. When the channel of the adjacent radio base station 12 is full blocked as the result of judgement at the inquiry time of the moving machine terminal 3, a signal indicating the alarm is transmitted to the moving machine terminal 3 through the radio base station 11. |
