A system for monitoring a person, for example a traveler, who is moving through a facility or a building and carries a biometric travel document and various electronic devices, for example mobile telephones, laptops, tablet computers, e-readers, notebooks, wireless headphones, smartwatches, or fitness trackers. An electronic controller communicates with an input device for inputting contents of the biometric travel document and for forwarding the contents for further processing. An electronically operated database generates a feature space in which the device characteristics are entered by the transceivers as a digital imprint of the traveler and which identifies the traveler with a particular probability resulting from the ratio of a weighted sum of the individual entries in the feature space to the maximum possible sum.