Anti theft system for e.g. goods in shop, comprises receiver stations with identification codes located outside neutral area and in communication with control device

摘要

A number of receiver stations (3-3) each provided with an identification code are located outside a neutral area (1, 1) containing the object(s) (7-7) to be monitored and are arranged strategically in a given pattern, at least one of the stations being located close to this area. Each receiver station includes a means for receiving a first signal from a transmitter device and a means for sending a second signal which includes the receiver station identification data upon receiving the first signal. A control device (C) receives and processes the second signal in order to determine the position of the object using the receiver station identification codes. The second signal is sent via GPRS (General Packet Radio Service) or GSM data.