Abstract: A radio frequency identification device (RFID) tag includes a processor, a memory configured to store an identification number that distinguishes the tag from other tags, and a transponder coupled to the memory and the processor. The tag arbitrates by selecting a random number in response to an inventory query from a reader. The tag responds to the reader depending on the random number selected. The tag is configured for multiple concurrent inventory session arbitrations with multiple readers by separately storing random numbers for respective inventory session arbitrations.

Abstract: Methods and systems of tagging objects and reading tags coupled to objects. At least some of the illustrative embodiments are systems comprising a reading antenna, a tag reader coupled to the reading antenna, and a radio frequency identification (RFID) tag comprising a tag antenna electromagnetically coupled to the reading antenna. The RFID tag couples to an object such as the body of a living organism or a metallic article. Moreover, the tag antenna has a far-field radiation pattern in a direction away from the object that is substantially unaffected by proximity of the RFID tag to the object, and substantially unaffected by which surface of the RFID tag faces the object.

Abstract: An RFID tag includes a base having at least one fold formed therein. An integrated circuit is formed on the base. At least one antenna segment extends from the integrated circuit and crosses the fold. When the fold is creased, a portion of the antenna segment on one side of the fold is aligned to be orthogonal to a portion of the antenna segment on the other side of the fold.

Abstract: Multi-Antenna element systems and related methods. At least some of the illustrative embodiments comprise a radio frequency identification (RFID) tag comprising an antenna system. The antenna system comprises a ground plane, a first antenna element on a first side of the ground plane, and a second antenna element on a second side of the ground plane opposite first antenna element. The illustrative RFID tag further comprises a first radio frequency identification circuit coupled to the first antenna element.

Abstract: A system is provided, which may alternatively be implemented as a method. According to one embodiment, the system comprises an article to be tracked; a flexible radio frequency identification (RFID) device coupled to the article, the RFID device comprising a first thin flexible sheet having a first surface, a dipole antenna disposed on the first sheet, and a single integrated circuit (IC) having stored therein an identification code associated with the article. The system further comprises an article tracking system configured to receive the identification code from an interrogation system, wherein the interrogation system includes a first interrogator located at a point of origin of the article, a second interrogator located at a point of destination of the article, and a third interrogator located on a route between the point of origin and the point of destination, and wherein the first, second, and third interrogators are configured to communicate with the RFID device to determine the identification code.

Abstract: A method of coordinating a plurality of RFID readers includes controlling the RFID readers such that only one of the readers performs an inventory of RFID tags at a time. A system for coordinating a plurality of RFID readers is also provided.

Abstract: A shipping container has a passive radio antenna element having internal and external antennas. A connector spanning the wall joins the two antennas. An internal communications device is disposed within the container and an external communications device is disposed external to the container. Another shipping container has a repeater element having internal and external antennas. A repeater unit spans the wall joining the two antennas. A communications device is disposed within the container and another communications device is disposed externally. RF signals are re-radiated by the antennas. Methodology includes emitting RF signals from a communication device disposed at a first location, receiving the signals through an antenna comprised by an antenna element, and re-radiating the signal from a second antenna comprised by the element, where the element spans the wall of a shipping container. The re-radiated signal is received by a second communications device disposed at a second location.

Abstract: An RFID (radio frequency identification device) tag comprising a processor; a memory configured to store an identification number that distinguishes the tag from other tags; a transponder coupled to the memory and the processor, the tag being configured to arbitrate by selecting a random number, in response to an inventory query from a reader, and to respond to the reader depending on the random number selected, the tag being further configured for multiple concurrent inventory session arbitrations with multiple readers by separately storing random numbers for respective inventory session arbitrations. RFID readers, systems, and methods are also provided.

Abstract: A method and system to determine physical parameters as between an RFID tag and a reader. At least some of the illustrative embodiments are methods comprising generating an antenna feed signal, and transmitting a first electromagnetic wave to a radio frequency device (by coupling the antenna feed signal to a reading antenna), receiving a backscattered electromagnetic wave from the radio frequency device to create a received signal, calculating a combined signal based on the antenna feed signal and received signal, and determining relative velocity between the radio frequency device and the reading antenna based on the combined signal.

Abstract: Selectively coupling to feed points of an antenna system. At least some of the illustrative embodiments are systems comprising an antenna system, an antenna communication circuit, a first diode coupled between the antenna communication circuit and a first feed point of the antenna system, and a second diode coupled between the antenna communication circuit and a second feed point of the antenna system. The antenna communication circuit is configured to couple the antenna communication circuit to the first and second feed points by forward biasing the diodes.

Abstract: A switch assembly selectively couples an antenna communication circuit to a first feed point of a first antenna, and selectively couples the antenna communication circuit to a second feed point of a second antenna. Each feed point is selected based on polarization of an electromagnetic wave to be radiated from or received by the corresponding antenna.

Abstract: A method and system to determine physical parameters as between a RFID tag and a reader. At least some of the illustrative embodiments are methods comprising generating an antenna feed signal, and transmitting a first electromagnetic wave to a radio frequency device (by coupling the antenna feed signal to a reading antenna), receiving a backscattered electromagnetic wave from the radio frequency device to create a received signal, calculating a combined signal based on the antenna feed signal and received signal, and determining relative velocity between the radio frequency device and the reading antenna based on the combined signal.

Abstract: Some embodiments include observable properties triggered upon interrogation of RFIDs. The RFIDs can be passive RFIDs, and the observable properties can be visible changes that require little power to generate, and little or no power to maintain. The visible information can include information about items tracked with the RFIDs, such as shipping information. Some embodiments include passive RFIDs utilizing a single antenna to power an integrated-circuit chip and a visual identifier. Some embodiments include methods of locating interrogated RFIDs. Some embodiments include methods of tracking items.

Abstract: A method of coordinating a plurality of RFID readers includes controlling the RFID readers such that only one of the readers performs an inventory of RFID tags at a time. A system for coordinating a plurality of RFID readers is also provided.

Abstract: A switch assembly selectively couples an antenna communication circuit to a first feed point of a first antenna, and selectively couples the antenna communication circuit to a second feed point of a second antenna. Each feed point is selected based on polarization of an electromagnetic wave to be radiated from or received by the corresponding antenna.

Abstract: An adjustable radio frequency data communications device has a monolithic semiconductor integrated circuit with integrated circuitry, interrogation receiving circuitry provided on the monolithic integrated circuit forming at least part of the integrated circuitry and configured to receive an interrogation signal from the interrogator unit, an antenna electrically coupled to the interrogation receiving circuitry and configured to communicate with the remote interrogator unit, a power source electrically coupled to the integrated circuitry and configured to generate operating power for the communications device, and at least one of the antenna and the interrogation receiving circuitry having reconfigurable electrical characteristics, the electrical characteristics being reconfigurable to selectively tune the at least one of the antenna and the interrogation receiving circuitry within a range of tuned and detuned states to realize a desired receiver sensitivity of the communications device.

Abstract: Methods and systems of determining physical characteristics associated with objects tagged with Radio Frequency Identification (RFID) tags. At least some of the illustrative embodiments are methods comprising receiving an electromagnetic signal transmitted by a radio frequency identification (RFID) tag coupled to an object (the receiving the electromagnetic signal in response to an interrogating signal), and determining orientation of the object based, at least in part, on the electromagnetic signal.

Abstract: The present invention teaches a method of manufacturing an enclosed transceiver, such as a radio frequency identification (“RFID”) tag. Structurally, in one embodiment, the tag comprises an integrated circuit (IC) chip, and an RF antenna mounted on a thin film substrate powered by a thin film battery. A variety of antenna geometries are compatible with the above tag construction. These include monopole antennas, dipole antennas, dual dipole antennas, a combination of dipole and loop antennas. Further, in another embodiment, the antennas are positioned either within the plane of the thin film battery or superjacent to the thin film battery.

Abstract: A simple trip-wire or magnetic circuit associated with a shipping container provides continuity, which is detected electrically. Simply, if continuity is disabled by a forced entry of the container, electrical detection means, such as a radio-frequency-identification (RFID) tag, will alert the owner or monitoring station. The trip-wire concept would require the replacing of a broken trip wire (resulting from forced entry), while the magnetic circuit concept can be reused repetitively. In a second embodiment a magnetic circuit and the detection device (RFID tag) are embedded into the shipping article during manufacturing. The preferred detection device, an RFID tag, could also be a battery backed transceiver type on which a replaceable or rechargeable battery could be mounted on the inside of the shipping container during manufacturing. The RFID tag would communicate with an interrogator unit, which could be connected to a host computer.

Abstract: A plurality of battery-operated transceivers encapsulated by lamination to form a sheet of independent transceivers is tested in a two piece fixture that forms an enclosure surrounding each in-sheet transceiver. Each enclosure has an antenna for transmitting a command signal to the transceiver at a known power level and for receiving a reply message from the transceiver containing a power level measurement made by the transceiver. Test methods using the fixture of the present invention are also described. Flexible radio frequency identification (RFID) devices are coupled to a roll of flexible material. Each RFID device coupled to the roll is advanced into a wireless communication region. An antenna in the region separately communicates with each of the RFID devices in a manner that isolates the communication from other REID devices counted to the roll outside the region.