Abstract: Methods and apparatuses for secure communications of confidential information are provided. In an embodiment, a method of communicating with a population of radio frequency identification tags includes transmitting a first interrogation signal, receiving a response to the first interrogation signal from at least one RFID tag at a first received signal strength including at least a portion of a first identification code, and transmitting a second interrogation signal that includes a request for confidential information, a command to transmit a response to the second interrogation signal at a secure power level, and the first identification code. In another embodiment, a method for communicating with an RFID tag includes receiving an interrogation signal that includes a request for confidential information and transmitting a response to the interrogation signal at a secure power level. The response includes the confidential information.

Abstract: An apparatus system, and techniques for detecting temperature change are disclosed. The system includes a temperature sensitive antenna that can be included in an RFID tag device. The antenna is associated with a temperature sensitive material that, upon being exposed to a particular temperature level over a time interval, causes at least one of a change in the resonance frequency of the antenna and change in antenna signal strength (e.g., antenna gain). An RFID reader is also provided that sends commands to the tag device and determines the existence of a temperature change based on a comparison of signal strengths received on different frequencies from the antenna.

Abstract: The present disclosure describes a system, methods and apparatus for determining a direction of motion of an RFID tag. An RFID reader is provided that includes an antenna that is tilted at a tilt angle with respect to a detection path. Response signals from the RFID tag are received at the antenna at different times, and an RSSI sample of each response signal is measured. Based on the RSSI samples, an RSSI/time data point is generated for each of the RSSI samples. Each RSSI/time data point defines a measured RSSI value for a particular RSSI sample versus a time that particular RSSI sample was measured. Based on the plurality of RSSI/time data points, the direction of motion of the RFID tag can be determined.

Abstract: Systems and methods for saving power in a distributed RFID system are provided. One RFID reader includes a RFID radio, a data communication radio, and a controller. The controller is configured to compare a current list of RFID tags responding to a current interrogation signal and a previous list of RFID tags responding to a previous interrogation signal to determine if there has been a change in RFID tags responding to the interrogation signals. The controller is also configured to command the data communication radio to transmit a signal to an external computing device if there has been the change in RFID tags, the signal indicative of the change, or not transmit the signal if there has not been a change. An RFID system includes a central computing device, multiple RFID tags, and multiple RFID readers similar to the above RFID reader.

Abstract: The present disclosure describes a system, methods and apparatus for displaying read range of a nomadic Radio Frequency Identification (RFID) reader based on feedback from fixed RFID beacon tags. For instance, the nomadic RFID reader can transmit an interrogation signal within a space that includes a plurality of fixed RFID beacon tags at known locations, and can receive response signals from a group of the fixed RFID beacon tags. Based on known locations of the group of fixed RFID beacon tags, a read range of the RFID reader can be determined. The read range is defined by the group of the fixed RFID beacon tags. The read range of the nomadic RFID reader can then be displayed on a display along with other information about the fixed RFID beacon tags and/or RFID item tags that are within the read range of the nomadic RFID reader.

Abstract: An apparatus system, and techniques for detecting temperature change are disclosed. The system includes a temperature sensitive antenna that can be included in an RFID tag device. The antenna is associated with a temperature sensitive material that, upon being exposed to a particular temperature level over a time interval, causes at least one of a change in the resonance frequency of the antenna and change in antenna signal strength (e.g., antenna gain). An RFID reader is also provided that sends commands to the tag device and determines the existence of a temperature change based on a comparison of signal strengths received on different frequencies from the antenna.

Abstract: Described is a system and method for determining determining a present state of charge of a battery and determining a rate of change of the state of charge of the battery, the rate of change being determined based on a charge current being supplied to the battery. Then, an updated state of charge is determined based on the rate of change.

Abstract: A wireless coverage map of a wireless network is generated as a function of a location of at least one access point and a first signal data collected at a plurality of locations within the network. The first signal data includes a first signal strength of a wireless signal communicated between the at least one access point and a wireless device. A second signal data is received. The second signal data includes a second signal strength of a further wireless signal communicated between one of the at least one access point and a further wireless device. The existence of the predetermined wireless network coverage condition is determined as a function of the second signal data and the wireless coverage map.

Abstract: Described is system and method for RFID tag communication including transmitting a command signal in a time slot to a plurality of wireless communication devices, the command signal indicating initiation of an identification process for identifying each of the wireless devices, the identification process including a plurality of time slots and computing a probability that a subsequent command signal transmitted in a subsequent time slot will cause only one of the wireless devices to transmit a response signal in the subsequent time slot.

Abstract: Described is a system and method for determining determining a present state of charge of a battery and determining a rate of change of the state of charge of the battery, the rate of change being determined based on a charge current being supplied to the battery. Then, an updated state of charge is determined based on the rate of change.

Abstract: Methods, systems, and apparatuses for wireless communication using a Radio Frequency Identification (RFID) protocol are described. The system includes a sensor for sensing a condition and converting it into electrical signals. The sensor is coupled to a near field transceiver. The near field transceiver formats the data collected by the sensor and transmits it wirelessly using an RFID protocol to a tag. A reader uses the RFID protocol to wirelessly read the data from the tag.

Abstract: Described is a method for determining an existence of a predetermined wireless network coverage condition. A wireless coverage map of a wireless network is generated as a function of a location of at least one access point and a first signal data collected at a plurality of locations within the network. The first signal data includes a first signal strength of a wireless signal communicated between the at least one access point and a wireless device. A second signal data is received. The second signal data includes a second signal strength of a further wireless signal communicated between one of the at least one access point and a further wireless device. The existence of the predetermined wireless network coverage condition is determined as a function of the second signal data and the wireless coverage map.

Abstract: Described is an arrangement including a receiver and an enveloped detection arrangement. The receiver receives radio frequency signals generated according to a predetermined wireless communication protocol. The envelope detection arrangement screens the radio frequency signals for a predetermined signal which utilizes the predetermined wireless communication protocol and has a predetermined envelope sequence. Upon detection of the predetermined signal, the arrangement transmits a further signal to a computing device coupled thereto. The further signal is an instruction for the computing device to execute a predetermined action.

Abstract: Described is a system and method for resilient coverage in a wireless environment. The system may include a first wireless device having a first wireless transceiver; a second wireless device having a second wireless transceiver; and an envelope detection arrangement (“EDA”) coupled to the second device. The second wireless device has a first communication mode and a second communication mode, The second wireless transceiver conducts wireless communications with the first wireless transceiver using a predetermined wireless communication protocol (e.g., IEEE 802.11/16) only when the second wireless device is in the first communication mode. The second wireless transceiver is in a low-power state when in the second communication mode. The EDA screens radio frequency signals for a signal having a predetermined envelope sequence; the signal is generated according to the same predetermined wireless communication protocol.

Abstract: The location of unmodified wireless assets in a wireless communication network may be identified using time differences of arrivals of a communication sequence at different network receivers. Time-stamping devices may include correlator circuits in parallel with signal decoders to time-stamp communication sequences. Cellular wireless networks may be frequency-multiplexed to increase spatial time-stamping density. Tags may be attached to passive assets to provide location identification information to network devices. Locations of assets broadcasting standard 802.11 radio frequency structures may be identified. Noise inherent in correlating a communication sequence may be reduced by using a selected correlation function.

Abstract: The location of unmodified wireless assets in a wireless communication network may be identified using time differences of arrivals of a communication sequence at different network receivers. Time-stamping devices may include correlator circuits in parallel with signal decoders to time-stamp communication sequences. Cellular wireless networks may be frequency-multiplexed to increase spatial time-stamping density. Tags may be attached to passive assets to provide location identification information to network devices. Locations of assets broadcasting standard 802.11 radio frequency structures may be identified. Noise inherent in correlating a communication sequence may be reduced by using a selected correlation function.

Abstract: The present invention proposes novel antenna means mounted on handheld devices and methods of use of such antenna means with multiple radios. The novel antenna means exhibit smaller sizes, good performance, have higher reliability, and exhibit novel hardware configurations. The novel methods of utilization for the antenna means comprise the reception of an 802.11 RF signal to the antennas, the acquisition step while a radio is determining which antenna has the better signal and acquiring signal from that antenna, and usage by the Bluetooth signal of the remaining antenna.

Abstract: The present invention relates generally to a system and method for determining the earliest time of arrival of a received signal in a wireless communications system. In particular, the present invention relates to a system and method for de-rotation of the carrier phase of a received signal to offset the effects of combining a received line-of-sight signal with various received multipath artifacts that may shift the complex phase of the received signal. The system and method of the present invention can improve the accuracy of the estimated time of arrival of a received signal by computing the time of arrival of the received signal at numerous different phase references and identifying the earliest of the computed times of arrival.

Abstract: The present invention relates generally to a system and method for determining the earliest time of arrival of a received signal in a wireless communications system. In particular, the present invention relates to a system and method for de-rotation of the carrier phase of a received signal to offset the effects of combining a received line-of-sight signal with various received multipath artifacts that may shift the complex phase of the received signal. The system and method of the present invention can improve the accuracy of the estimated time of arrival of a received signal by computing the time of arrival of the received signal at numerous different phase references and identifying the earliest of the computed times of arrival.