Plasmonic-surface antenna systems are described in which resonators, or cells, are closely arranged but do not touch. At least a portion of a radiating surface includes a plurality of cells (operative as resonators) placed very close together to one so that a surface (plasmonic) wave causes near replication of the current of one cell in an adjacent cell. Cells with one or more fractal shapes may be used as a fractal plasmonic surface (FPS). Systems and/or methods are described of using plasmonic surfaces or fractal plasmonic surfaces for radiofrequency identification (RFID). A PS or FPS may act as an intermediary array of antennas, which can serve to connect an RFID reader with one or more RFID tags. Structures including cages are described that can include one or more surfaces that are each an FPS. Methods of power transfer are described.

Techniques are provided to estimate the location of an RFID tag using tag read information, such as a tag read count or a tag read rate, and an opportunity metric, such as an inventory cycle duration, inventory cycle rate, or inventory cycle count. A tag tracking system determines read information for a tag in a zone and an opportunity metric associated with the tag and the zone. The tag tracking system then computes a success rate based on the tag read information and opportunity metric, and uses the success rate to estimate the location of the tag.

An antenna device includes a feed coil and a sheet conductor. The feed coil includes a magnetic core and a coil-shaped conductor, which is provided around the magnetic core. An RFIC is connected to the feed coil. The sheet conductor has a larger area than the feed coil. A slit that extends from a portion of the edge of the sheet conductor toward the inner side of the sheet conductor is provided in the sheet conductor. The feed coil is arranged such that the direction of the axis around which the feed coil is disposed is parallel or substantially parallel to the directions in which the sheet conductor extends. The feed coil is arranged such that the feed coil is close to the slit and one of coil openings at the ends of the feed coil faces the slit.

A sheet having a front surface and a rear surface is configured for linking a first electronic device with a second electronic device, and includes a first communication device for wirelessly connecting to the first electronic device, a second communication device for wirelessly connecting to the second electronic device, at least one switch element operatively connected to the first communication device or the second communication device, and a data communication link between the first communication device and the second communication device.

A device facilitates personalizing an integrated circuit card including a fingerprint sensor. The device includes a support sheet, a first antenna located on top of and in contact with a surface of the support sheet, and at least one second antenna located on top of and in contact with the surface of the support sheet. The at least one second antenna is connected to the first antenna.

Synthesized-beam RFID readers may be used to locate RFID tags. In one embodiment, a tag's response rates on different beams can be used, along with the target locations of those beams, to estimate the tag's location. The estimated tag location is within a region where beams with nonzero tag response rates overlap, and the distances of the estimated tag location from any two different beam target locations may correspond to a ratio of tag response rates on the two different beams. In another embodiment, a tag's response rates on different beam pairs configured to cooperatively power RFID tags can be used, along with the target locations of those beam pairs, to estimate the tag's location.

Plasmonic-surface antenna systems are described in which resonators, or cells, are closely arranged but do not touch. At least a portion of a radiating surface includes a plurality of cells (operative as resonators) placed very close together to one so that a surface (plasmonic) wave causes near replication of the current of one cell in an adjacent cell. Cells with one or more fractal shapes may be used as a fractal plasmonic surface (FPS). Systems and/or methods are described of using plasmonic surfaces or fractal plasmonic surfaces for radiofrequency identification (RFID). A PS or FPS may act as an intermediary array of antennas, which can serve to connect an RFID reader with one or more RFID tags. Structures including cages are described that can include one or more surfaces that are each an FPS. Methods of power transfer are described.

Exemplary embodiments are directed to wireless power transfer including generating an electromagnetic field at a resonant frequency of a transmitter to create a coupling-mode region within a near field of the transmitter during a synchronization portion of a time-multiplexed recurring period. During a power transmission portion of the recurring period, the electromagnetic field will continue to be generated when there is a receiver within the coupling-mode region, or the electromagnetic field will be disabled when there are no receivers within the coupling-mode region. Different segments of the power transmission portion are allocated to different receivers. The transmitter issues serial commands to the receivers by on/off keying the electromagnetic field. The receivers issue serial replies by changing the amount of power consumed from the electromagnetic field between two different states. The serial commands and serial replies are used to determine the number of receivers, their power requirements, and the allocation of segments.

A tank support system includes a hollow open-top container having a contiguous sidewall region and a bottom region coupled to the sidewall region. A loop antenna is coupled to a portion of the container's sidewall region. A tuning circuit coupled to the loop antenna provides for adjustment of the loop antenna's electrical impedance. A radio frequency identification (RFID) reader is coupled to the tuning circuit.

Plasmonic-surface antenna systems are described in which resonators, or cells, are closely arranged but do not touch. At least a portion of a radiating surface includes a plurality of cells (operative as resonators) placed very close together to one so that a surface (plasmonic) wave causes near replication of the current of one cell in an adjacent cell. Cells with one or more fractal shapes may be used as a fractal plasmonic surface (FPS). Systems and/or methods are described of using plasmonic surfaces or fractal plasmonic surfaces for radiofrequency identification (RFID). A PS or FPS may act as an intermediary array of antennas, which can serve to connect an RFID reader with one or more RFID tags. Structures including cages are described that can include one or more surfaces that are each an FPS. Methods of power transfer are described.