Abstract: A system is provided for processing articles in a warehousing or merchandising operation wherein information bearing electronically coded labels are attached to the articles to be processed. The system uses the principle of electromagnetic communication in which an interrogator containing a transmitter generates an electromagnetic signal which is transmitted to electronic labels containing label receiving antennas. The electronic labels are attached to articles as they are processed. Each label antenna receives a proportion of the transmitted energy and operates a reply generation circuit connected either to the label receiving antenna or a separate label reply antenna with the result that an information bearing electromagnetic reply signal is radiated by the label.

Abstract: An identification and telemetry system including an interrogator (1) containing an interrogator antenna (2) for generating at an interrogation frequency, an interrogtion signal. The interrogation signal is adapted to excite over an electromagnetic coupling path (M1) at least one coded label (3) containing a label antenna (4) and a label microcircuit (5). The coded label is adapted to extract energy from the label antenna and to generate a label reply signal. The label reply signal is adapted to be conveyed to a label reply antenna and, via an electromagnetic coupling path, to a receiver in the interrogator. The label antenna is placed in proximity to a further antenna (6) being a parasitic antenna coupled electromagnetically (M2, M3) with the interrogator antenna and with the label antenna so as to enhance transfer of power between the interrogator and the coded label.

Abstract: A system for detecting presence of and for communicating with an electronic coded label. The coded label includes a presence signaling antenna, a label circuit and a data communications antenna. The system includes presence detection means for creating a presence detection electromagnetic field and data communications means for creating an interrogation electromagnetic field. The label circuit is adapted to operate in a first mode when the electromagnetic field to which the label is exposed is at a first power level, said first mode being that of a linear circuit with an impedance dependent upon frequency. The label circuit is adapted to operate in a second mode when the electromagnetic field to which the label is exposed is at a second power level, said second mode being that of a non-linear circuit with behavior dependent upon time.

Abstract: The present invention relates to a system for automated identification of articles such as baggage or carrier cargo wherein an electronic sub system called an interrogator including a transmitter and receiver extracts by electromagnetic means useful information from an electronically coded label attached to such items as they are processed through the sorting operations at an airport or node of an article handling organization.

Abstract: An identification system having an electronic label for processing articles such as baggage or carrier cargo. The system uses the principle of electromagnetic communication in which an interrogator containing a transmitter generates an electromagnetic field through which the electronic label containing a label receiving antenna may pass. The electronic label is attached to the article being processed and includes means for sensing the electromagnetic field and means for generating intermittently repeated label reply signals. The system includes a receiver for detecting and decoding the label reply signal. The electronic label replies intermittently as long as it is within the electromagnetic field, and the field is maintained for a period of time which is greater than the time interval between the intermittently repeated label replies.

Abstract: An identification and telemetry system comprising: a signal responding label including a first antenna for receiving an interrogation signal and for scattering a reply signal, an impedance connected to the first antenna, means for generating the reply signal and means for varying the impedance connected to the first antenna in accordance with the reply signal; and an interrogator comprising a second antenna for transmitting an interrogation signal and for receiving the reply signal, a transmitter connected to the second antenna and including a generator of pulsed radio frequency energy, means for separating the reply signal from the transmitted signal, a receiver connected to the second antenna and means within the receiver for detecting and decoding the reply signal.