Portable position signaling device has data source, and transmitter-receiver for cellular communications system for transmitting signal to trigger action, e.g. transition time measurement

摘要

The portable position signaling device (P) has a data source and a transmitter-receiver for a cellular communications system (K) for transmitting an action signal containing data to it to trigger one of a number of defined actions. One of the defined actions is to determine the transition time differences occurring for the data transmission between the position signaling device and at least two fixed base stations (B1-B3) of the communications system to enable derivation of the position signalling device.