Abstract: For tracing objects distributed transmitter stations are provided, each transmitting an activation signal. Tags are attached to objects. The tags receive the activation signals when in an operating area of one of the transmitter stations. The received activation signal causes the tag to transmit a reaction signal. A receiver station receives the reaction signals. Data representing positions of tags in accordance with the received reaction signals are registered. The activation signals each also include a transmitter station code associated to the transmitter station transmitting that signal. The transmitter station codes transmitted by different transmitter stations are mutually different. The reaction signals transmitted by the tags each include the transmitter station code included in the received activation signal that caused the tag to transmit that reaction signal.