Abstract: Techniques for detecting radio-frequency identification (RFID) tags are disclosed. For example, an exit control system is described that detects unauthorized removal of articles from a protected facility. A series of antennas are setup to produce interrogation corridors located near the exit of the protected area. RFID tags are attached to the articles to be protected. Each tag includes information that uniquely identifies the article to which it is affixed and status information as to whether the articles removal from the facility is authorized. The RF reader outputs RF signals through the antennas to create electromagnetic fields within the interrogation corridors. The reader outputs RF power from a single port to the multiple antennas via a splitter/combiner. In this way, a single RF reader with only one transmitter/receiver port simultaneously interrogates multiple antennas. A variety of techniques are described by which the reader can detect the removal of an unauthorized article.

Abstract: An item monitoring system and method of using an item monitoring system. The present invention relates more particularly to an item monitoring system including a sensor, that senses a plurality of items in a first amount of space associated with the sensor and that senses both items containing metal and items containing no metal, a communications network, and a computer that receives information from the sensor through the communications network. The present invention also relates more particularly to a method of monitoring items to determine the number of items within a first amount of space associated with the sensor.

Abstract: A passport reader for processing a passport having an RFID element associated therewith. A exemplary embodiment of the invention provides a passport reader for processing a passport having an RFID element associated therewith including an RFID interrogation source for interrogating and obtaining information from the RFID element associated with a passport; and an antenna to transmit signals between an RFID element and the RFID interrogation source.

Abstract: An item monitoring system and method of using an item monitoring system. The present invention relates more particularly to an item monitoring system including a sensor, that senses a plurality of items in a first amount of space associated with the sensor and that senses both items containing metal and items containing no metal, a communications network, and a computer that receives information from the sensor through the communications network. The present invention also relates more particularly to a method of monitoring items to determine the number of items within a first amount of space associated with the sensor.

Abstract: Techniques for detecting radio-frequency identification (RFID) tags are disclosed. For example, an exit control system is described that detects unauthorized removal of articles from a protected facility. A series of antennas are setup to produce interrogation corridors located near the exit of the protected area. RFID tags are attached to the articles to be protected. Each tag includes information that uniquely identifies the article to which it is affixed and status information as to whether the articles removal from the facility is authorized. The RF reader outputs RF signals through the antennas to create electromagnetic fields within the interrogation corridors. The reader outputs RF power from a single port to the multiple antennas via a splitter/combiner. In this way, a single RF reader with only one transmitter/receiver port simultaneously interrogates multiple antennas. A variety of techniques are described by which the reader can detect the removal of an unauthorized article.

Abstract: Techniques for detecting radio-frequency identification (RFID) tags are disclosed. For example, an exit control system is described that detects unauthorized removal of articles from a protected facility. A series of antennas are setup to produce interrogation corridors located near the exit of the protected area. RFID tags are attached to the articles to be protected. Each tag includes information that uniquely identifies the article to which it is affixed and status information as to whether the articles removal from the facility is authorized. The RF reader outputs RF signals through the antennas to create electromagnetic fields within the interrogation corridors. The reader outputs RF power from a single port to the multiple antennas via a splitter/combiner. In this way, a single RF reader with only one transmitter/receiver port simultaneously interrogates multiple antennas. A variety of techniques are described by which the reader can detect the removal of an unauthorized article.