Abstract: A system for electromagnetically interrogating electronically coded labels is provided. The system includes at least one electromagnetically interrogatable electronic coded label, an interrogator containing a generator of electromagnetic interrogation signals and a receiver of electromagnetic reply signals from the label. The system is adapted to make use of electromagnetic signals, other than those generated by the interrogator, which may reach the label.

Abstract: A system is disclosed for secure communication between an interrogator and an RFID tag. The system includes means for singulating the tag in a population of RFID tags and means for extracting from the tag, identity data adapted to uniquely identify the tag. The system further includes means for securely communicating the identity data to a secure database, means for providing authentication data by the database and means for securely communicating the authenticating data to the interrogator. The system also includes means for providing a further communication between the tag and the interrogator, and wherein at least one stream of data between the tag and the interrogator includes random data generated via a random physical process. The tag and database may each include means for maintaining a count of secure authentications. The count may be separately maintained by the tag and database and may be incremented following each secure authentication.

Abstract: The invention provides a system and method for interrogating one or more electronic labels attached to objects, the system including an interrogation device capable of radiating an electromagnetic interrogation signal which contains information in the form of a plurality of symbols, each symbol being represented by a respective time interval between consecutive dips in amplitude of the interrogation signal. The one or more of the electronic labels are capable of detecting and decoding the interrogation signal to recover the symbols, and in response to recovering the symbols generate a reply signal. The reply signal is able to be detected and decoded by the interrogation device. It is envisaged that the invention will find particular use in identifying, sorting, controlling and/or auditing objects having information bearing electronically coded labels.

Abstract: The present invention provides a system and method for communicating between an interrogation device and at least one electronic label device. The system includes an interrogation device for generating an interrogation field using an interrogation signal. The interrogation signal contains angle modulation and amplitude modulation such that the amplitude modulation encodes the interrogation signal with information for communication to one or more of the electronic labels. The angle modulation is controllably varied so that the interrogation signal has a frequency spectrum which includes sidebands having reduced amplitudes. The system also includes one or more electronic labels locatable within the interrogation field and capable of detecting and decoding the interrogation field so as to recover the information.

Abstract: A system for electromagnetically interrogating electronically coded labels is provided. The system includes at least one electromagnetically interrogatable electronic coded label, an interrogator containing a generator of electromagnetic interrogation signals and a receiver of electromagnetic reply signals from the label. The system is adapted to make use of electromagnetic signals, other than those generated by the interrogator, which may reach the label.

Abstract: The invention provides a system and method for interrogating one or more electronic labels attached to objects, the system including an interrogation device capable of radiating an electromagnetic interrogation signal which contains information in the form of a plurality,of symbols, each symbol being represented by a respective time interval between consecutive dips in amplitude of the interrogation signal. The one or more of the electronic labels are capable of detecting and decoding the interrogation signal to recover the symbols, and in response to recovering the symbols generate a reply signal. The reply signal is able to be detected and decoded by the interrogation device. It is envisaged that the invention will find particular use in identifying, sorting, controlling and/or auditing objects having information bearing electronically coded labels.

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: 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: 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: The invention consists of a method and apparatus for article sorting wherein an electronically interrogatable label is provided for and attached to each article, the label bearing indicia indicative of a serial number, instructions relating to the routing of the label bearing those indicia being fed into a suitable computing system arranged to control the operation of sorting devides on receipt of a signal from a reader arranged to interrogate the label. The term "label" is intended to include any device such as, for example, a tag, capable of carrying the necessary indicia and of being attached to an article to be sorted.