Abstract: Systems and methods to selectively attach and control antennas via diodes. In one embodiment, a system includes: a reader having a plurality of reader antennas of different polarizations to transmit radio frequency signals; and at least one radio frequency device. The radio frequency device includes: a plurality of tag antennas of different polarizations; a plurality of diodes coupled to the plurality of tag antennas respectively; a receiver coupled to the plurality of diodes to receive the radio frequency signals from the tag antennas when the diodes are forward biased; and a set of one or more current controllers coupled to the plurality of diodes. In a receiving mode the controllers selectively forward bias the diodes to receive the signals from the reader. In a transmitting mode the controllers selectively change the state of the tag antennas to transmit data via backscattering the radio frequency signals.

Abstract: Systems and methods to selectively attach and control antennas via diodes. In one embodiment, a system includes: a reader having a plurality of reader antennas of different polarizations to transmit radio frequency signals; and at least one radio frequency device. The radio frequency device includes: a plurality of tag antennas of different polarizations; a plurality of diodes coupled to the plurality of tag antennas respectively; a receiver coupled to the plurality of diodes to receive the radio frequency signals from the tag antennas when the diodes are forward biased; and a set of one or more current controllers coupled to the plurality of diodes. In a receiving mode the controllers selectively forward bias the diodes to receive the signals from the reader. In a transmitting mode the controllers selectively change the state of the tag antennas to transmit data via backscattering the radio frequency signals.

Abstract: A suture button is provided that is adapted for soft tissue fixation. In one aspect, the button includes a textured bottom surface that allows gripping the soft tissue material and distributing the tension that holds the soft tissue to the bone thereby reducing the likelihood the soft tissue tearing.

Abstract: Systems and methods to determine kinematical parameters of physical objects using radio frequency identification (RFID) tags attached to the objects. In one embodiment, one of a population of RFID tags is selectively instructed by an RFID reader to backscatter the interrogating electromagnetic wave and thus allow the RFID reader to measure the position, speed, acceleration, and/or jerk of the object to which the tag is attached. The RFID reader combines the signal representing the backscattered interrogating electromagnetic wave and the signal representing the interrogating electromagnetic wave transmitted by the RFID reader to determine or monitor one or more of the kinematical parameters of the object.

Abstract: Systems and methods to use radar systems for radio frequency identification (RFID) applications. The radar systems can be adapted to use RFID communications protocols and methods to enhance the usefulness of radar systems beyond the determination of the presence, distance, direction and/or speed of a vehicle or object, to additionally include the transmission of data such as object identification and additional messages or data.

Abstract: A radio frequency device utilizing an antenna having a single antenna structure resonant on multiple resonant frequency ranges. The antenna can be configured to operate within multiple frequency ranges for communication according to respective protocols associated with the respective frequency ranges.

Abstract: A radio frequency device utilizing an antenna having a single antenna structure resonant on multiple resonant frequency ranges. The antenna can be configured to operate within multiple frequency ranges for communication according to respective protocols associated with the respective frequency ranges.

Abstract: Systems and methods to use radar systems for radio frequency identification (RFID) applications. The radar systems can be adapted to use RFID communications protocols and methods to enhance the usefulness of radar systems beyond the determination of the presence, distance, direction and/or speed of a vehicle or object, to additionally include the transmission of data such as object identification and additional messages or data.

Abstract: Systems and methods to selectively attach and control antennas via diodes. In one embodiment, a system includes: a reader having a plurality of reader antennas of different polarizations to transmit radio frequency signals; and at least one radio frequency device. The radio frequency device includes: a plurality of tag antennas of different polarizations; a plurality of diodes coupled to the plurality of tag antennas respectively; a receiver coupled to the plurality of diodes to receive the radio frequency signals from the tag antennas when the diodes are forward biased; and a set of one or more current controllers coupled to the plurality of diodes. In a receiving mode the controllers selectively forward bias the diodes to receive the signals from the reader. In a transmitting mode the controllers selectively change the state of the tag antennas to transmit data via backscattering the radio frequency signals.

Abstract: Systems and methods to selectively attach and control antennas via diodes. In one embodiment, a system includes: a reader having a plurality of reader antennas of different polarizations to transmit radio frequency signals; and at least one radio frequency device. The radio frequency device includes: a plurality of tag antennas of different polarizations; a plurality of diodes coupled to the plurality of tag antennas respectively; a receiver coupled to the plurality of diodes to receive the radio frequency signals from the tag antennas when the diodes are forward biased; and a set of one or more current controllers coupled to the plurality of diodes. In a receiving mode the controllers selectively forward bias the diodes to receive the signals from the reader. In a transmitting mode the controllers selectively change the state of the tag antennas to transmit data via backscattering the radio frequency signals.

Abstract: Systems and methods to determine motion parameters of physical objects using radio frequency identification (RFID) tags attached to the objects. In one embodiment, a method implemented in a radio frequency identification (RFID) system includes determining a motion parameter of the RFID tag based on detecting a Doppler frequency shift in a radio frequency signal received from the RFID tag.

Abstract: Systems and methods to determine motion parameters of physical objects using radio frequency identification (RFID) tags attached to the objects. In one embodiment, a method implemented in a radio frequency identification (RFID) system includes determining a motion parameter of the RFID tag based on detecting a Doppler frequency shift in a radio frequency signal received from the RFID tag.

Abstract: Systems and methods to determine kinematical parameters of physical objects using radio frequency identification (RFID) tags attached to the objects. In one embodiment, one of a population of RFID tags is selectively instructed by an RFID reader to backscatter the interrogating electromagnetic wave and thus allow the RFID reader to measure the position, speed, acceleration, and/or jerk of the object to which the tag is attached. The RFID reader combines the signal representing the backscattered interrogating electromagnetic wave and the signal representing the interrogating electromagnetic wave transmitted by the RFID reader to determine or monitor one or more of the kinematical parameters of the object.

Abstract: A radio frequency device utilizing an antenna having a single antenna structure resonant on multiple resonant frequency ranges. The antenna can be configured to operate within multiple frequency ranges for communication according to respective protocols associated with the respective frequency ranges.

Abstract: Systems and methods to determine kinematical parameters of physical objects using radio frequency identification (RFID) tags attached to the objects. In one embodiment, one of a population of RFID tags is selectively instructed by an RFID reader to backscatter the interrogating electromagnetic wave and thus allow the RFID reader to measure the position, speed, acceleration, and/or jerk of the object to which the tag is attached. The RFID reader combines the signal representing the backscattered interrogating electromagnetic wave and the signal representing the interrogating electromagnetic wave transmitted by the RFID reader to determine or monitor one or more of the kinematical parameters of the object.

Abstract: Systems and methods to selectively attach and control antennas via diodes. In one embodiment, a system includes: a reader having a plurality of reader antennas of different polarizations to transmit radio frequency signals; and at least one radio frequency device. The radio frequency device includes: a plurality of tag antennas of different polarizations; a plurality of diodes coupled to the plurality of tag antennas respectively; a receiver coupled to the plurality of diodes to receive the radio frequency signals from the tag antennas when the diodes are forward biased; and a set of one or more current controllers coupled to the plurality of diodes. In a receiving mode the controllers selectively forward bias the diodes to receive the signals from the reader. In a transmitting mode the controllers selectively change the state of the tag antennas to transmit data via backscattering the radio frequency signals.

Abstract: Systems and methods to determine motion parameters of physical objects using radio frequency identification (RFID) tags attached to the objects. In one embodiment, a method implemented in a radio frequency identification (RFID) system includes determining a motion parameter of the RFID tag based on detecting a Doppler frequency shift in a radio frequency signal received from the RFID tag.

Abstract: A radio frequency device utilizing an antenna having a single antenna structure resonant on multiple resonant frequency ranges. The antenna can be configured to operate within multiple frequency ranges for communication according to respective protocols associated with the respective frequency ranges.

Abstract: Systems and methods to selectively attach and control antennas via diodes. In one embodiment, a system includes: a reader having a plurality of reader antennas of different polarizations to transmit radio frequency signals; and at least one radio frequency device. The radio frequency device includes: a plurality of tag antennas of different polarizations; a plurality of diodes coupled to the plurality of tag antennas respectively; a receiver coupled to the plurality of diodes to receive the radio frequency signals from the tag antennas when the diodes are forward biased; and a set of one or more current controllers coupled to the plurality of diodes. In a receiving mode the controllers selectively forward bias the diodes to receive the signals from the reader. In a transmitting mode the controllers selectively change the state of the tag antennas to transmit data via backscattering the radio frequency signals.

Abstract: Systems and methods to determine kinematical parameters of physical objects using radio frequency identification (RFID) tags attached to the objects. In one embodiment, one of a population of RFID tags is selectively instructed by an RFID reader to backscatter the interrogating electromagnetic wave and thus allow the RFID reader to measure the position, speed, acceleration, and/or jerk of the object to which the tag is attached. The RFID reader combines the signal representing the backscattered interrogating electromagnetic wave and the signal representing the interrogating electromagnetic wave transmitted by the RFID reader to determine or monitor one or more of the kinematical parameters of the object.