Patent application number | Description | Published |
20080252424 | Stochastic Communication Protocol Method and System For Radio Frequency Identification (Rfid) Tags Based on Coalition Formation, Such as For Tag-To-Tag Communication - Data carriers (such as RFID tags) are formed into clusters of data carriers. Each cluster has at least one bridge data carrier that can communicate with a bridge data carrier of another cluster, thereby allowing data carriers in each cluster to communicate directly or indirectly with each other using a stochastic communication protocol method. Direct tag-to-tag communication capability is provided between data carriers in each cluster and/or between clusters. The data carriers can backscatter and modulate a carrier wave from a source, thereby using the backscattered and modulated carrier wave to convey data to each other. | 10-16-2008 |
20090085749 | SYSTEMS AND METHODS FOR WIRELESSLY MARKING MEDIA - A media marking transponder system includes a media fastener and a wireless transponder circuit coupled to the media fastener. The antenna for the wireless transponder circuit has a first effective length when no piece of media is fastened to the media fastener and a second, different effective length when at least one piece of media is fastened to the media fastener. | 04-02-2009 |
20090174557 | COMPACT FLEXIBLE HIGH GAIN ANTENNA FOR HANDHELD RFID READER - A compact flexible high gain antenna is disclosed which includes a co-planar array of at least three substantially parallel main conducting antenna elements, a reflector, a driven element, and a director. Each of these elements may be terminated on the ends by a stub element, and the reflector and the director may include an intermediate meander element. Stub elements capacitively load the antenna, while meander elements inductively load the antenna, and the loading affects the resonant frequency of the antenna. The conducting antenna elements may be affixed to a flexible dielectric substrate and may be bent or curved into different compact shapes, suitable for fitting manufacturing form factors for a handheld RFID reader. The antenna has a high directional gain which results in a longer operating range. | 07-09-2009 |
20090189816 | NEAR-FIELD AND FAR-FIELD ANTENNA-ASSEMBLY AND DEVICES HAVING SAME - Systems, methods, and devices wirelessly communicate in a near-field region and a far-field region. A device may include a near-field antenna and a far-field antenna. The device may be configured to selectively operate in a near-field mode, employing the near-field antenna, and/or in a far-field mode, employing the far-field antenna, and/or in a joint mode, employing both the near-field antenna and the far-field antenna separately or concurrently. One type of device may be a wireless communications data-reader device configured for both near-field and far-field communications. Another type of device may be a wireless communications data-provider device configured for both near-field and far-field communications. | 07-30-2009 |
20090219141 | PHASE HOPPING TO REDUCE INTERFERENCE AND IMPROVE RADIO FREQUENCY IDENTIFICATION (RFID) TAG THROUGHPUT - A radio frequency identification (RFID) reader outputs an interrogation signal, and hops/varies the phase of the interrogation signal sent by the RFID reader over time. Varying the phase of the interrogation signal enables the RFID reader to provide, for each zone of an RF field of the RFID reader, a particular phase that reduces of the effects of interference RF signal(s) present in that zone of the RF field. Reducing the interference in each zone of the RF field increases the throughput of RFID tags that can be successfully read by the RFID reader. | 09-03-2009 |
20090219158 | RFID TAGS WITH ENHANCED RANGE AND BANDWIDTH OBTAINED BY SPATIAL ANTENNA DIVERSITY - Spatial antenna diversity is used with RFID tags to reduce sensitivity to multi-path fading. RFID tags can use a single multi-port chip or multiple multi-port chips. The ports of the chip or chips are coupled to separated feedpoints on one or more antennas. | 09-03-2009 |
20090231142 | SYSTEM AND METHOD FOR DETERMINING RFID TAG PLACEMENT - In systems and methods for determining the placement of radio-frequency identification (RFID) tags, a tag reader communicates with one or more RFID tags at different locations of a target object. The tag reader determines which of the different locations is a preferable location for placing an RFID tag by detecting the transmission power level or other value required to communicate with the RFID tag at each of the different locations. | 09-17-2009 |
20090251288 | METHOD AND APPARATUS FOR RFID TAG DETECTION AND CHARACTERIZATION - This disclosure discloses methods and apparatus for detecting and characterizing radio-frequency identification (RFID) tags. | 10-08-2009 |
20090251379 | WIRELESS ENCODER APPARATUS AND METHODS - A wireless encoder for encoding a plurality of wireless communication devices carried by media comprises a shielded enclosure having an exterior surface defining an aperture; a wireless signal generator to excite the shielded enclosure; and a media path along which media carrying a plurality of wireless communication devices travels. The media path passes across the aperture outside the shielded enclosure. | 10-08-2009 |
20100102931 | WIRELESS TRANSPONDER SYSTEM WITH POLARIZATION MODULATION - A wireless transponder system includes at least one antenna configured to send transponder signals. The wireless transponder system also includes a wireless transponder circuit coupled to the at least one antenna, the wireless transponder circuit having a first state for sending transponder signals of a first polarization type and a second state for sending transponder signals of a second polarization type different than the first polarization type, and the wireless transponder circuit configured to encode information in a sequence of the transponder signals of the first polarization type alternating with the transponder signals of the second polarization type. | 04-29-2010 |
20100103053 | CIRCULARLY POLARIZED ANTENNA - A circularly polarized antenna includes a generally helical wire defining a generally cylindrical passage having a first end and a second end. A first ground plane is proximate the first end of the generally cylindrical passage and has a width substantially equal to a diameter of the generally cylindrical passage. A cable extends through the generally cylindrical passage and is electrically coupled to the first ground plane and to the generally helical wire proximate the first end. | 04-29-2010 |
20100328073 | METHOD AND SYSTEM TO DETERMINE THE POSITION, ORIENTATION, SIZE, AND MOVEMENT OF RFID TAGGED OBJECTS - A method and system of determining spatial identification of an object, such as orientation, size, location, range, and/or movement, using an RFID system is disclosed. An RFID system can comprise one or more RFID reader receiving antennas that query one or more RFID tags coupled to the object. The measurement of the phase of the tag responses at the reader antennas and phase differentials as a function of distance, frequency, and time are the basis of spatial identification. The system can work with conventional Gen 2 tags and readers without modification of the tags or protocol. | 12-30-2010 |
20110187507 | AUTOMATIC DATA COLLECTION DEVICE, METHOD AND ARTICLE - A radio frequency identification system comprises a radio-frequency identification substrate and an interrogator. In one embodiment, the radio-frequency identification substrate comprises a plurality of radio-frequency identification devices. In one embodiment, a controller on the substrate controls a first one of the plurality of radio-frequency identification devices based on a state of a second one of the plurality of radio-frequency identification devices. In one embodiment, an antenna system includes an S-shaped portion electrically coupled to an integrated circuit along a central portion of the S-shaped portion. Adjusting the parameters of the segments making up the S-shaped portion controls performance characteristics of a radio-frequency identification device. | 08-04-2011 |
20120139711 | METHOD AND APPARATUS TO ESTIMATE THE NUMBER OF TRANSPONDERS IN A FIELD - A total number of transponders in an interrogation field is estimated or determined based on demodulated baseband direct and quadrature components from a plurality of collided responses from multiple transponders, including collided responses from which information encoded therein cannot be recovered, and would conventionally be discarded. A query or Q value may be set without an a priori knowledge of the actual number or even approximate number of transponders in the field of the interrogator or reader. Such may allow transponders to be quickly and efficiently singulated, for example in a single pass, and information read from and/or written to singulated transponders. | 06-07-2012 |
20120176227 | METHOD AND APPARATUS TO MITIGATE MULTIPATH IN RFID - A distance between at least one antenna of an interrogation system and a transponder, such as an RFID tag, is determined based on derivatives with respect to frequency of the phase and the signal strength of responses transmitted by the transponder and received at the at least one antenna. The derivatives of the phase and the signal strength facilitate compensating for sources of multipath interference. Determining changes in distance may further facilitate determining location, speed, or bearing of the transponder by the interrogation system. | 07-12-2012 |
20120229259 | STOCHASTIC COMMUNICATION PROTOCOL METHOD AND SYSTEM FOR RADIO FREQUENCY IDENTIFICATION (RFID) TAGS BASED ON COALITION FORMATION, SUCH AS FOR TAG-TO-TAG COMMUNICATION - Data carriers (such as RFID tags) are formed into clusters of data carriers. Each cluster has at least one bridge data carrier that can communicate with a bridge data carrier of another cluster, thereby allowing data carriers in each cluster to communicate directly or indirectly with each other using a stochastic communication protocol method. Direct tag-to-tag communication capability is provided between data carriers in each cluster and/or between clusters. The data carriers can backscatter and modulate a carrier wave from a source, thereby using the backscattered and modulated carrier wave to convey data to each other. | 09-13-2012 |
20130249736 | SYNTHETIC APERTURE RFID HANDHELD WITH TAG LOCATION CAPABILITY - A system for determining a bearing or location of a radio frequency identification (RFID) tag using a handheld RFID reader is described. In one embodiment, the reader is equipped with an accelerometer. A user moves the reader while the reader receives the tag's signal and determines the tag signal's phase at multiple locations. The locations of the reader antenna can be reconstructed using the accelerometer data. By using the phase determined at multiple locations in conjunction with the location of the reader antenna, the reader can determine the bearing of the tag. For an RFID reader not equipped with an accelerometer, the sign and ratio of the rate of change in the phase of a tag's signal to the distance traveled by the reader antenna can be used to determine the location of the tag relative to the reader. | 09-26-2013 |
20140375501 | WIRELESSLY RECONFIGURABLE ANTENNA - A reconfigurable antenna element is controlled using a wirelessly powered and wirelessly activated switch, where the antenna element is part of an antenna or antenna array. A control signal for reconfiguring the antenna element is embedded into a wirelessly transmitted data signal for transmission by the antenna. | 12-25-2014 |
20150084771 | SYSTEMS, METHODS, AND APPARATUS TO PERMIT COMMUNICATION BETWEEN PASSIVE WIRELESS TRANSPONDERS - Passive wireless transponders can perform transponder-to-transponder communication when illuminated by an interrogation carrier wave. The transponder-to-transponder communication permits each transponder to determine the identity of “other” proximately transponders. The transponder-to-transponder communication optionally permits each transponder to identify a “nearest neighbor” using one or more backscatter signal properties such as received signal strength or time-of-flight. Using this information and one or more externally supplied or internally stored instruction sets transponders can provide neighboring transponder data to an interrogator. Using this “neighbor” data, the interrogator can provide a system user with data indicative of the relative locations of a plurality of tags arranged in a one or two dimensional matrix. | 03-26-2015 |