Large-scale comparison between buoy and SSM/I drift

Detecting a wireless terminal being taken from a facility. In a first embodiment, a base station is assigned to each exit from the facility. The base station uses a directional antenna which only communicates with wireless terminals within the exit area. When a wireless terminal enters the exit area and registers on the base station, the base station transmits the registration information to a wireless switching system that immediately places a telephone call to the user of the wireless terminal to inform them that they have not turned in their wireless terminal. Alernatively, in a third embodiment, after the wireless terminal is registered, the base station rather than the wireless switching system places a telephone call to the user of the wireless terminal to inform them that they have not turned in their wireless terminal. In a second embodiment of the invention, a transmission signal separate from the frequencies utilized for voice and data communication by the wireless switching system is utilized to alert the wireless terminal to the fact that the wireless terminal is in an exit area. The wireless terminal is responsive to this alerting to place a call to the wireless switching system to inform the wireless switching system of this fact. The wireless switching system then alerts the user via the wireless terminal.

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