WO2003098175A1 - Method for measuring temperature using a remote, passive, calibrated rf/rfid tag including a method for calibration - Google Patents

Classifications

• • G—PHYSICS
  • G06—COMPUTING; CALCULATING OR COUNTING
  • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
  • G06K19/00—Record carriers for use with machines and with at least a part designed to carry digital markings
  • G06K19/06—Record carriers for use with machines and with at least a part designed to carry digital markings characterised by the kind of the digital marking, e.g. shape, nature, code
  • G06K19/067—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components
  • G06K19/07—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips
  • G06K19/0716—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips at least one of the integrated circuit chips comprising a sensor or an interface to a sensor
  • G06K19/0717—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips at least one of the integrated circuit chips comprising a sensor or an interface to a sensor the sensor being capable of sensing environmental conditions such as temperature history or pressure
• • G—PHYSICS
  • G01—MEASURING; TESTING
  • G01K—MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR
  • G01K3/00—Thermometers giving results other than momentary value of temperature
  • G01K3/02—Thermometers giving results other than momentary value of temperature giving means values; giving integrated values
  • G01K3/04—Thermometers giving results other than momentary value of temperature giving means values; giving integrated values in respect of time
• • G—PHYSICS
  • G06—COMPUTING; CALCULATING OR COUNTING
  • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
  • G06K19/00—Record carriers for use with machines and with at least a part designed to carry digital markings
  • G06K19/06—Record carriers for use with machines and with at least a part designed to carry digital markings characterised by the kind of the digital marking, e.g. shape, nature, code
  • G06K19/067—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components
  • G06K19/07—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips
  • G06K19/0723—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
  • G06K19/0724—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs the arrangement being a circuit for communicating at a plurality of frequencies, e.g. for managing time multiplexed communication over at least two antennas of different types
• • G—PHYSICS
  • G06—COMPUTING; CALCULATING OR COUNTING
  • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
  • G06K19/00—Record carriers for use with machines and with at least a part designed to carry digital markings
  • G06K19/06—Record carriers for use with machines and with at least a part designed to carry digital markings characterised by the kind of the digital marking, e.g. shape, nature, code
  • G06K19/067—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components
  • G06K19/07—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips
  • G06K19/077—Constructional details, e.g. mounting of circuits in the carrier
  • G06K19/07749—Constructional details, e.g. mounting of circuits in the carrier the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card
• • G—PHYSICS
  • G06—COMPUTING; CALCULATING OR COUNTING
  • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
  • G06K19/00—Record carriers for use with machines and with at least a part designed to carry digital markings
  • G06K19/06—Record carriers for use with machines and with at least a part designed to carry digital markings characterised by the kind of the digital marking, e.g. shape, nature, code
  • G06K19/067—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components
  • G06K19/07—Record carriers with conductive marks, printed circuits or semiconductor circuit elements, e.g. credit or identity cards also with resonating or responding marks without active components with integrated circuit chips
  • G06K19/077—Constructional details, e.g. mounting of circuits in the carrier
  • G06K19/07749—Constructional details, e.g. mounting of circuits in the carrier the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card
  • G06K19/07758—Constructional details, e.g. mounting of circuits in the carrier the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card arrangements for adhering the record carrier to further objects or living beings, functioning as an identification tag
• • G—PHYSICS
  • G06—COMPUTING; CALCULATING OR COUNTING
  • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
  • G06K7/00—Methods or arrangements for sensing record carriers, e.g. for reading patterns
  • G06K7/0008—General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• • G—PHYSICS
  • G07—CHECKING-DEVICES
  • G07C—TIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE
  • G07C9/00—Individual registration on entry or exit
  • G07C9/20—Individual registration on entry or exit involving the use of a pass
  • G07C9/28—Individual registration on entry or exit involving the use of a pass the pass enabling tracking or indicating presence

Definitions

• the present invention relates to a system that includes a passive, remote radio frequency identification (RFID) tag, and a control device, such as an active smart RFID tag or RFID reader/writer that can communicate with the passive tag giving it energy and receiving data from it and that can analyze and store data so received.
• RFID radio frequency identification
• the system would further require a reader/writer that can instruct the active RFID tag and can read data created during use of the tags.
• the system will be utilized primarily in the transport and storage field, or any other field of use where detecting changes in temperature at distance without the use of a direct probe is desirable.
• the system utilizes a unique means for determining temperature, which means forms part of this patent application. This invention further claims a methodology of calibration to provide accurate temperature measurements (in the range of +/- 0.1 degree C).
• Inexpensive temperature sensing devices are generally designed to record only a single excursion outside a preset temperature window. More expensive temperature logging devices are typically bulkier and too costly for single use or disposable applications.
• a further limitation of prior art is the requirement to retrieve a tag from a shipping box to take a reading or download data from it.
• Electronic sensing and recording devices that can do this are available; they include thermistors or other temperature sensors, a clock, a battery, a memory in which temperature data are recorded, and some form of output mechanism (such as a plug-in port) whereby the recorded data can be read for interpretation by an interested party at a later time.
• These devices are large in size compared to the disposable tags, and significantly more expensive. They are generally reusable. In some cases, for example where the container's size is small relative to the size of the sensing and recording device or extreme temperatures that would affect battery performance are of interest, they require probes containing a temperature sensor that destroys the integrity of the container. Where the container is large enough to accommodate a sensing and recording device, the device must be removed from the container when it reaches its destination to allow it to be reused.
• RFID tags are in wide use for identifying and tracking all manner of packages and items.
• RFID technology uses electromagnetic or electrostatic coupling in the radio frequency (RF) range of the electromagnetic spectrum to identify uniquely an object of interest.
• RFID is increasingly supplementing or replacing bar coding for identification purposes and providing electronic packing slip functions in the shipping and logistics industry as it does not require direct contact or line-of-sight scanning.
• a passive RFID system comprises an antenna and transceiver (usually combined as a reader) and a transponder (RFID tag).
• the antenna generates a RF signal that activates the RFID tag.
• the activated tag then transmits data back to the antenna.
• the data may be used to notify a logic controller to initiate an action, or stored for subsequent retrieval by an interested party.
• a further limitation is the adverse effect of decreasing temperature on the battery, making the device impractical for very cold applications (such as monitoring dry-ice packaged goods) without the addition of a temperature probe containing a thermistor, which destroys the integrity of the package, or the use of expensive low temperature battery technology.
• the present invention combines a low cost passive RFID tag (slave tag) with an active RFID master tag and an RF writer/reader in a system that senses and records temperature at preprogrammed intervals.
• the low cost of the slave tag makes it feasible to be used as a disposable temperature sensor.
• a further implementation of this invention combines a low cost passive RFID tag (slave tag) with an RF writer/reader in a recording system, omitting the master tag.
• the slave tag is inserted in a package or container whose internal temperature is of interest.
• the master tag polls the slave tag at preprogrammed intervals via RF signal, and the slave tag transmits data (such as its unique ID and/or manufacturer code) back to the master tag by RF signal.
• the master tag can then determine the temperature of the environment into which the slave tag has been inserted by way of calculating the frequency shift caused by such ambient temperature from its nominal calibrated frequency (see below for method of calibration).
• the master RFID tag comprises an integrated circuit with programmable or re-programmable procedure memory, battery, antenna, clock, high-stability oscillator such as piezo-electric, quartz or ceramic resonator, and volatile or non-volatile data memory.
• the master tag can be pre-programmed at the time of manufacture or can be programmed prior to use using the RF writer/reader.
• the temperature data calculated from the frequency shift during data transmission sessions by the slave tag are stored in the master tag's data memory-
• the stored temperature data can be downloaded via RF writer/reader by someone interested in the temperature to which the container contents have been exposed.
• the slave tag comprises a procedure memory programmed with calibration data (if required, as described below), optional data such as ID, manufacturer codes, electronic packing slip information etc., Manchester-type phase encoder, oscillator whose frequency is temperature sensitive such as a tick oscillator, and a resonator such as an antenna coil, printed antenna, ceramic antenna, etc.
• the temperature sensitive oscillator of the slave tag replaces a thermistor or other direct temperature sensing device as the means of determining the temperature, eliminating the need for a battery in the slave tag. This reduces the cost of manufacturing the slave tag and eliminates the problem of a battery's voltage being temperature sensitive.
• any ISO standard RFID tag can be used for this function, adding little or no additional cost to logistic systems already utilizing such RFID tags to track shipments.
• temperature is measured by comparing the stable oscillator frequency of the master tag to the frequency of the slave tag's tick oscillator, a semi-conductor device whose frequency is predictably dependent on temperature.
• the master tag's antenna is calibrated to receive signals in the frequency range of interest, determined by the range of temperature to which the slave tag might be exposed and the range of frequencies that would result from such temperatures.
• the temperature at the slave tag would influence the tick count of its oscillator, which would be known to have a predictable change in tick frequency in response to changes in temperature.
• Penc period of Manchester encoder pulses
• Tf sigmoid type function
• temp temperature
• the relationship between temperature and frequency would be calibrated prior to use and stored in the procedure memory of the master tag. It could also be stored in the slave tag's procedure memory, instead of or part of its ID. Deviation of the returning RF signal's frequency from that of the stable oscillator in the master tag would be determined and compared to the frequency-temperature calibration data for the slave tag's oscillator. The resulting calculated temperature at the slave tag would then be recorded in the master tag's temperature data memory. As indicated above, the data could be stored in the slave tag's memory, perhaps after having been calculated and recorded at the master tag. At a later time, a party interested in the temperature to which the container was exposed could download the stored temperature data from the master tag using a RF or other type of reader.
• the slave tag In use, the slave tag is placed inside a container at the time of shipping or at the time of manufacture of such container.
• the master tag is placed outside the container in close proximity, such as attached to the container by adhesive or other means.
• the master tag is programmed to cause the slave tag to transmit data to it at intervals of interest to the user.
• the master tag polls the slave tag by transmitting an RF signal that excites the slave tag's tick oscillator and provides energy to the device.
• the Slave tag responds by transmitting an RF signal that can be detected by the master tag. Because of the sensitivity of the slave tag's tick oscillator to changes in temperature, its signal will deviate from the master tag's RF frequency according to a predictable relationship.
• Calibration data for the slave tag's temperature-frequency relationship will be stored either in the slave tag's or master tag's memory, and the difference in frequency from the transmitted RF signal to the received RF signal will be applied to the calibration data to determine the temperature at the slave tag. This will be time stamped and recorded in the master tag's data memory, or possibly in the slave tag's memory.
• the slave tag could be inserted into a temperature insulated chamber containing a thermoelectric element (atti Peltier). The temperature could be changed rapidly and with precision, allowing Penc t
• PencBA to be determined.
• the specific function can then be calculated for this tag sample and stored in the procedure memory of the slave tag from which it would be downloaded to the master tag or writer/reader to be used in temperature determination. This would obviate the necessity of uniquely pairing slave and master tags.
• the temperature-frequency function might equally be stored in the procedure memory of the master tag if specific master-slave pairs are to be used. From this function the temperature can be computed for any value of Penc.
• each tag would be calibrated.
• calibration could be generalized to the design and components of a particular type of slave tag (such as a standard RFID tag produced by a particular manufacturer) and therefore avoid the requirement for individual calibration of each tag.
• a generic calibration coefficient would be sufficient to provide temperature measurements in the +/- 1 degree C range, if not better.
• the temperature data can be retrieved from the master tag or from the slave tag, if stored there, by an interested party.
• the master tag can be single use or multiple use and may be reprogrammable. Petersen and Wilson describe various means by which this might be done.
• the slave tag can also be single use or reusable
• the master tag is omitted from the system and the passive RFID slave tag is inserted into a package or container.
• the temperature at the RFID tag at that time could also be determined and processed (stored, downloaded) by the reader. This would allow a central database to keep track of the time and internal temperature of the package at each waypoint in systems where such packages are already being scanned and tracked using barcodes and/or RFID tags.
• the package ID, electronic packing slip, other logistics related information, manufacturer code (to facilitate "generic" calibration - see above) and temperature sensitive components could be combined in a single passive RFID tag, thereby eliminating the requirement for additional hardware to provide the benefit of temperature measurements, by utilizing RFID readers and passive RFID tags already incorporated into the logistics infrastructure of shipping and courier companies.

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• Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Theoretical Computer Science (AREA)
• Computer Hardware Design (AREA)
• Microelectronics & Electronic Packaging (AREA)
• Artificial Intelligence (AREA)
• Computer Vision & Pattern Recognition (AREA)
• Computer Networks & Wireless Communication (AREA)
• Measuring Temperature Or Quantity Of Heat (AREA)
• Arrangements For Transmission Of Measured Signals (AREA)

Abstract

Description

Claims

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

Family

ID=29425959

Family Applications (1)

Country Status (3)

Cited By (111)

Families Citing this family (4)

Citations (4)

• 2002
  • 2002-05-21 CA CA002387106A patent/CA2387106A1/en not_active Abandoned
• 2003
  • 2003-05-21 WO PCT/CA2003/000746 patent/WO2003098175A1/en not_active Application Discontinuation
  • 2003-05-21 AU AU2003229460A patent/AU2003229460A1/en not_active Abandoned

Patent Citations (4)

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