| 摘要 |
PURPOSE:To increase the use efficiency of a circuit by identifying whether a call starts in the beginning or ending of the same zone for securing a call time, and varying the number of block zones. CONSTITUTION:For example, when an up mobile station in an E zone among base station zones originates, A-G zones 102 are blocked. Namely, the number of blocked zones is so judged that when the mobile station is in the beginning of the presence zone, the presence zone and one front zone corresponds to the secured call time and when the station is close to the end of the presence zone, one rear zone and four front zones are included. A zone switching signal is received and a timer which detects zones is put in operation to measure the position of a train; when a hook signal for the start of a call arrives, a signal of blocking A is sent corresponding to the train position before the middle of the presence zone on the basis of the collation result of the timer circuit and a signal of blocking B is sent out corresponding to the train position behind the middle of the zone. Those signals are received by a base station and an antenna signal is stopped to perform the blocking. |
