Rfmicron, Inc.

Xilinx, Inc.

Sigmatel, Inc.

Shahriar Rokhsaz

Brian David Young

Ahmed Younis

Marwan M Hassoun

Edwin De Angel

John James Paulos

Mathew A Rybicki

H Spence Jackson

Moises Emanuel Robinson

Brian Taylor Brunn

Jinghui Lu

Abhay Misra

Benjamin Cooke

Michael A Nix

Tanmay Zargar

Alan Wayne Hansford

Guanghui Hu

Martin Gutierrez

Firas Najeh Abughazaleh

Stephen D Anderson

Earl E Swartzlander, Jr

Yvette P Lee

Michael Ren Kent

Stanley Drobac

Kazi S Hossain

Greg Pitner

A radio frequency identification (RFID) tag includes an antenna, an analog front end, a processing circuit, and memory. The analog front end includes a power circuit, a tuning circuit, a transmitter, and a receiver. The power circuit is operably coupled to convert a radio frequency (RF) signal into a power supply voltage. The tuning circuit, when enabled, adjusts an RF characteristic of the analog front end to tune power harvesting from the RF signal. The transmitter is operably coupled to transmit a response signal to the RFID reader via the antenna. The receiver is operably coupled to receive a command signal from the RFID reader, wherein the command signal is contained within a portion of the RF signal. The processing circuit is operable to interpret the command signal and generate the response signal.

Pressure based wireless sensor and applications thereof

A method includes processing, by a processing module of a data logging device, a plurality of log commands. The processing of a log command of the plurality of log commands includes obtaining a measure of an environmental condition. The processing further includes updating a status of the environmental condition based on the measure of an environmental condition. The method further includes determining, by the processing module, the updated status of the environmental condition after the plurality of log commands have been processed. When the updated status of the environmental condition is favorable, the method further includes generating, by the processing module, a favorable environmental condition signal.

Data logging with pass indication

A method includes establishing, by a data logging device, a sleep mode. The method further includes receiving, by a processing module of the data logging device, a second activation command that causes the data logging device to transition to a standby mode. The method further includes receiving, by the processing module, a third activation command that causes the data logging device to transition to a ready mode. The method further includes receiving, by the processing module, a fourth activation command that causes the data logging device to transition to a logging mode. In the logging mode, the method further includes obtaining, by the processing module, a log command. In response to the log command, the method further includes obtaining, by the processing module, a measure of an environmental condition. The method further includes storing the measure of the environmental condition in memory of the data logging device.

Method and apparatus of data logging

A method includes receiving, by an RF receiving circuit of a passive wireless sensor of a wireless communication system, an RF signal. When a sensing element of the passive wireless sensor is exposed to an environmental condition, the method further includes affecting, by the sensing element, resonant frequency of the RF receiving circuit. The method further includes determining, by a processing module of the passive wireless sensor, a first value for an adjustable element for a known environmental condition, determining a second value for the adjustable element for an unknown environmental condition, determining a difference between the first and second values that correspond to a change, generating a coded value representative of the change, and transmitting the coded value. The method further includes receiving, by a second processing module of a sensor computing device of the wireless communication system, the coded value and determining a sensed environmental condition.

Method for sensing environmental conditions

A method includes receiving, by a radio frequency identification (RFID) tag, a radio frequency (RF) signal from an RFID reader. When the RF signal includes a command, the method further includes interpreting, by the RFID tag, the command to determine a field strength shell of interest. When the RFID tag is in the field strength shell of interest, the method further includes further interpreting, by the RFID tag, the command to determine a type of request, and providing, by the RFID tag, a response regarding the type of request to include one or more of a matched impedance value generated in response to the RF signal, a field strength reference current generated in response to the RF signal, and a digital value representative of an environmental condition.

Generating a response by a radio frequency identification (RFID) tag within a field strength shell of interest

A passive wireless temperature sensor includes a radio frequency (RF) front end having a variable input impedance. The RF front end includes an antenna operable to receive an RF signal having a particular carrier frequency and a tuning circuit having a resonant frequency corresponding to the particular carrier frequency. The passive wireless temperature sensor further includes one or more temperature sensing elements coupled to the RF front end. When sensing a temperature, the one or more temperature sensing elements cause a change in the variable input impedance. The passive wireless temperature sensor further includes a processing module operably coupled to the RF front end operable to adjust the resonant frequency of the tuning circuit to compensate for the change in the variable input impedance and generate a coded value representative of the change. The coded value representative of the change corresponds to the sensed temperature.

Computing device for processing environmental sensed conditions

A radio frequency identification (RFID) tag includes a power harvesting circuit that operates generate power for the RFID tag from a continuous wave of a radio frequency (RF) signal. The RFID tag further includes a tuning circuit that is tuned based on a capacitance setting, where the capacitance setting is indicative of a power level of the power. The RFID tag further includes a processing module operably coupled to the tuning circuit, where the processing module operates to generate the capacitance setting to obtain a desired power level for the power.

Radio frequency identification (RFID) moisture tag(s) and sensors with extended sensing via capillaries

A radio frequency (RF) circuit includes a tank circuit having a selectively variable impedance. The RF circuit further includes a tuning circuit adapted to dynamically vary the impedance of the tank circuit, and to develop a first quantized value representative of a change to impedance of the tank circuit. The RF circuit further includes a detector circuit adapted to develop a second quantized value representative of a field strength of a received RF signal.

Radio frequency (RF) field strength detecting circuit

A method begins by a radio frequency identification (RFID) reader transmitting a first and second radio frequency (RF) signal of a plurality of RF signals, which each include a unique carrier frequency and an instruction to an RFID tag to respond with a received power level indication. The method continues by the RFID reader receiving, in response to the first and second signals sent at a first and second carrier frequency, a first and second response from the RFID tag that includes a first and second received power level indication. The method continues by the RFID reader determining an estimated resonant frequency of the RFID tag based on the first and second received power level indications and the first and second carrier frequencies.

RFID reader to determine an estimated resonant frequency of a RFID tag

A method includes sending, by a reader, a radio frequency (RF) signal to a wireless sensor that includes an antenna having a tail section and a head section. The tail section is for placement in an RF limited area for sensing moisture in a first location of a vehicle under test and wherein the head section is for placement in a non-RF limited area. The method further includes receiving, by the reader, an RF response to the RF signal from the wireless sensor. The first RF response includes an indication of adjustment of one or more RF characteristics of the wireless sensor, which corresponds to a variance of the one or more RF characteristics from a desired value, which, in turn, corresponds to a level of moisture at the first location. The method further includes outputting, by the reader, a message regarding the level of moisture at the first location.

Sensor with tail or transmission line for vehicle leak testing

A method includes transmitting, by a radio frequency identification (RFID) reader, a series of RF signals to a plurality of RF receiver circuits in a time sequence. The first RF signal commands the plurality of RF receiver circuits to remain silent when received signal strength of the first RF signal corresponds to a power level greater than a first power level. The method further includes receiving one or more sets of responses from one or more sets of RF receiver circuits of the plurality of RF receiver circuits in response to the series of RF signals. The method further includes determining an area of interest based on the one or more sets of responses, determining a set of power levels corresponding to the area of interest, and transmitting a second series of RF signals to the plurality of RF receiver circuits in a second time sequence.

Received power level for RF receiver circuit processing prioritization

A wireless sensor includes a radio frequency (RF) front end, a sensing element, and a processing module. The RF front end sends a coded digital value to a sensing computing device via an RF signal. The sensing element senses an environmental condition of an item. The processing module determines an effect on an operational parameter of an RF front end of the wireless sensor as a result of the sensing element sensing the environmental condition. The processing module also adjusts tuning of the RF front end to mitigate the effect on the operational parameter and equates an amount of adjusting of the tuning of the RF front end to the coded digital value.

Wireless sensor with oppositely positioned antenna and sensing circuitry

A wireless communication system includes a plurality of wireless sensors. A wireless sensor includes a radio frequency (RF) receiving circuit, and a sensing element, where the sensing element affects the resonant frequency of the RF receiving circuit. The wireless sensor further includes a processing module operable to determine a first value for an adjustable element of a plurality of elements for a known environmental condition, a second value for the adjustable element for an unknown environmental condition, a difference between the first and second values that corresponds to a change, and to generate a coded value representative of the change. The wireless communication system further includes one or more sensor computing devices coupled to the plurality of wireless sensors via a network. A sensor computing device includes a second processing module operable to receive the coded value and determine a sensed environmental condition based on the coded value.

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Austin, TX, United States of America

Shahriar Rokhsaz