PURPOSE: To effectively manage presence or office attending/leaving by discriminating whether a person is present or absent depending whether a mobile station is within or at the outside of a coverage of an exchange.
CONSTITUTION: A master set 101 sends a polling request massage (PM) to all base stations 109A-109C through I/F 108A-108C for presence confirmation. The master set 101 starts a reply watchdog timer and a storage area of a reply confirmation message of a management storage area 106 of a RAM 105 is set to be a non-reception state. The base station 109 receiving the PM from the master set 101 makes polling of a mobile station 111. The mobile station 111 receiving the polling signal returns a reply signal to the base station 109. The station 109 extracts an identification signal of the station 111 and sends a reply confirmation signal including the identification signal to the set 101. The set 101 refers to the area 106 from the identification code and sends an attendant notice message including a person identification code to a host computer 113. Futhermore, when the reply confirmation message is not received, the absence notice message including the person identification code is set to the computer 113.
