Base station for control system controlling access to secured area

摘要

The base station (1), for a control system, has a device (3,5,7,9) for communication with a mobile part (2) which is moved by an object to obtain access to a room or area secured by the control system. The base station (1) has a sensor (11) which is responsive to the object being removed from the secured area. When the sensor responds, the communication device (3,5,7,9) carries out a communication attempt with the mobile part (2), to determine whether the object has taken the mobile part with it. The arrangement includes a signal generator (12). This provides a signal when the object does not take the mobile part with it. The sensor may be directed to detect the opening of a door. The communication device may have a wireless transmitter/receiver with directional characteristics directed to an access to the room.