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WO2009034534A2 - Rfid à ports multiples et son procédé de fabrication et d'utilisation - Google Patents

Rfid à ports multiples et son procédé de fabrication et d'utilisation Download PDF

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Publication number
WO2009034534A2
WO2009034534A2 PCT/IB2008/053664 IB2008053664W WO2009034534A2 WO 2009034534 A2 WO2009034534 A2 WO 2009034534A2 IB 2008053664 W IB2008053664 W IB 2008053664W WO 2009034534 A2 WO2009034534 A2 WO 2009034534A2
Authority
WO
WIPO (PCT)
Prior art keywords
port
tag
target
chip
magnitude
Prior art date
Application number
PCT/IB2008/053664
Other languages
English (en)
Other versions
WO2009034534A3 (fr
Inventor
Gaetano Marrocco
Original Assignee
Universita' Degli Studi Di Roma 'tor Vergata'
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Universita' Degli Studi Di Roma 'tor Vergata' filed Critical Universita' Degli Studi Di Roma 'tor Vergata'
Publication of WO2009034534A2 publication Critical patent/WO2009034534A2/fr
Publication of WO2009034534A3 publication Critical patent/WO2009034534A3/fr

Links

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
    • G06K19/077—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
    • G06K19/0716—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
    • 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
    • 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
    • G06K19/0776—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 the adhering arrangement being a layer of adhesive, so that the record carrier can function as a sticker
    • 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
    • G06K19/07766—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 comprising at least a second communication arrangement in addition to a first non-contact communication arrangement
    • G06K19/07767—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 comprising at least a second communication arrangement in addition to a first non-contact communication arrangement the first and second communication means being two different antennas types, e.g. dipole and coil type, or two antennas of the same kind but operating at different frequencies

Definitions

  • the present invention relates to the field of so-called RFID (Radio Frequency Identification) devices, i.e. devices adapted for identifying objects in general and/or monitoring some physical-chemical magnitudes related thereto.
  • RFID Radio Frequency Identification
  • a RFID system typically consists of an apparatus, commonly referred to as a reader, which queries a transponder, commonly referred to as a tag, which replies to the request by sending its identification, commonly referred to as an ID.
  • the reader queries the tag by emitting an electromagnetic signal that hits the tag which, if passive, takes the energy for replying therefrom thus sending its identification.
  • a tag is formed by electronic devices including storage means and an antenna for communicating with the reader and for picking up the radiated energy in order to support communications.
  • the electronic devices normally integrated in a single chip, are connected by means of a pair of terminals, referred to as a port.
  • the reply message may vary in relation to the query message sent by the reader.
  • Said reply is retrieved from an internal memory of the tag.
  • Active tags which are more cumbersome as they have their own power source, are further provided with at least one sensor adapted to detect and measure a specific magnitude and a microcontroller which handles the acquisition of the data and the communication thereof to the reader.
  • the reception and trasmission frequencies are typically in the UHF band.
  • Such systems may allow the real-time monitoring of determined magnitudes.
  • data related to a moving target may be acquired when a network of readers exists in the surrounding environment. i
  • the possibility of monitoring a magnitude opens the way to innumerable applications which involve all fields of science, medicine, industry and agriculture.
  • monitoring a magnitude imposes electronic configurations based on a microcontroller which typically requires a source of energy inside the tag.
  • the present invention thus aims at reaching the objects discussed above by making a multiple-port RFID in accordance with claim 1.
  • Another object of the invention is to provide a method for manufacturing multiple- port tags and a method of decoding the signals reflected by the tag in order to be able to obtain an estimate of at least one physical-chemical or geometric property of the target, such as for example the dielectric permittivity or the electric conductivity or its geometry.
  • a further object of the present invention is to provide a querying procedure of a multiple-port tag by a reader.
  • the present invention suggests to reach such objects by disclosing a method for manufacturing and a method for arranging a multiple-port tag, in addition to a method for estimating a physical-chemical or geometric magnitude of a target, in accordance with claims 7, 8 and 10, respectively.
  • the multiple-port RFID, object of the present invention advantageously allows to: a) classify the equivalent dielectric constant of the target in a discrete set of values, returning the closest value to the real value; b) estimate the dielectric constant or other physical-chemical or geometric features of the target, or of the over-time variations thereof, within a continuous set of values.
  • Fig. 1 shows the interaction between a reader and a multiple-port tag, which replies to a query with N different replies, as many are the chips defining the tag;
  • Fig. 2 shows a multiple-port tag including an antenna and three chips connected to said antenna by means of an equal number of ports of different impendence;
  • Fig. 3 shows a multiple-port tag including three chips connected to an equal number of antennas of different shape and impendence
  • Fig. 4 shows two possible multiple-port tag embodiments including an antenna and two chips connected to said antenna by means of a distributed matching network having two different impendence ports;
  • Fig. 5 refers to a flow chart related to a querying procedure of a multiple-port tag by a reader
  • Fig. 6 shows a chart which may be used to estimate the dielectric permittivity of a target
  • Fig. 7, 8 and 9 refer to an example in which the multiple-port tag includes two chips connected to two antennas of equal shape and different dimensions, applied by means of an adhesive substrate to a generic object;
  • Fig. 10 shows a tag embodiment with two chips consisting of two meander antennas for classifying the content of bottles
  • Fig. 11 , 12, 13 and 14 refer to an experimental setup aimed at monitoring the filling level of a box. Detailed description of preferred embodiments of the invention
  • a preferred variant of multiple-port tag includes an antenna connected to at least two chips by means of as many different impedance ports (Fig. 2).
  • the multiple-port tag includes two or more antennas, each of which is connected to one or more chips (Fig. 3).
  • a reader queries a multiple-port tag
  • each chip defining the tag on the basis of the sequence communicated by the reader, responds by modulating the query waveform.
  • the signal reflected by each chip of the tag is further influenced by the antenna gain and port impedance, thus providing information about the features of the target.
  • a multiple-port tag with different input impedances of each port replies with as many signals of different amplitude.
  • a specific case is that in which a single chip, named singular, receives energy in order to be able to reply to the reader, while all the other chips belonging to the same tag are not matched to the corresponding port.
  • a second query is required to the reader to obtain the value of the measurand magnitude stored from the chip for which the corresponding port is matched.
  • the difference between the amplitudes of the various signals emitted by the tag, and thus between the powers carried thereby, depends on the geometric and chemical-physical conformation of the target.
  • the reader queries a multiple-port tag and picks up the reply signals thus identifying the object and estimating the value and/or the variations of the geometric and/or chemical-physical features of the material forming the target.
  • the geometry of the conductors forming a multiple-port tag may either be of the wire or of the planar type, based on slots, dipoles, loops or patches.
  • a method of manufacturing multiple-port tags for example adapted to monitor the dielectric permittivity of the target, includes the following steps:
  • Arranging antennas dimensioned according to any known optimization algorithm, acting for example on their shape and size and on the position of the ports so that the n-th port has an input impendence matched to the input impendence of the chip when this is arranged on a reference target with permittivity ⁇ n of the type similar to the candidate targets.
  • these may be scaled versions of a same basic shape. The scaling coefficient is related to the reference permittivity value associated to the specific port.
  • the single radiating element or antenna is connected to two or more chips by means of an impendence matching network made with concentrated or distributed constant elements so that the impedances seen from the two or more ports are subject to the same above-mentioned constraints.
  • Possible, non-limiting embodiments of the matching network are shown in Fig. 4 and consist in two reciprocally engaged stubs, either connected to the antenna or radiating dipole (Fig. 4a) or placed in a specular position with respect to the radiating dipole (Fig. 4b).
  • the vertical dimensions si and S 2 and the horizontal dimensions I 1 and I 2 of the stubs need to be optimized by any method in order to obtain the required impendence condition.
  • a reader in accordance with the present invention, includes:
  • - processing means adapted to decode a signal radiated by a tag, to measure the power thereof and to estimate a geometric and/or physical-chemical property of the target, as well as the over-time variation thereof in relation to the reference values stored in said storage means.
  • the measurement curves or tables which allow, for the specific application and for the specific grade of antennas, to associate reply signals of a multiple-port tag to the magnitudes to be measured are stored in said storage means of the reader.
  • a preferred embodiment is examined below, wherein the measurand magnitude is the dielectric permittivity of the target.
  • the measurand magnitude is the dielectric permittivity of the target.
  • such an example is not intended to be limitative.
  • M may represent the ratio between minimum powers which must be provided to the reader in order to independently activate the two chips.
  • said curve is obtained a priori by using an electromagnetic calculation program which allows to represent the geometry of the multiple-port tag and thus to estimate the reply signals generated by its chips, i.e. to estimate the minimum powers required to the reader to remotely activate the two tags upon the variation of the permittivity of a reference target having features close to the candidate targets.
  • a same analysis method may be used to monitor further features of the target, such as for example the shape or other magnitude, such as temperature or mechanical strain.
  • a method for estimating a measurand magnitude, e.g. permittivity, of the target will now be described with reference to the block chart in figure 5, distinguishing the case in which the reader receives a single reply from the case in which it receives two replies:
  • step 1 - querying a tag arranged on the target (step 1);
  • step 2 - receiving the reply from said tag and extracting at least one ID identification code (step 2); - if there is only one reply (step 3), e.g. when there is a singular chip, a new query is carried out (3.1) by the reader to obtain (3.2) the permittivity value stored in said storage means or memory of the chip;
  • step 4 if two replies with two different IDs are received (step 4), i.e. if the permittivity of the target is such that more than one chip is sufficiently matched to the port impedance, then calculating the powers, Pi and P 2 , associated to said replies, (4.1), calculating (4.2) a value M 12 equal to the ratio P 1 /P 2 and accessing (4.3) the abscissa axis of the aforesaid decoding curve or measurement table from which the permittivity of the target on the ordinate axis in relation to said value of M 12 is estimated (4.4). Furthermore, the values of the distance between reader and tag, with which such permittivity value is identified, is obtained from the same curve.
  • the procedure may further be carried out by calculating Mi 2 as a ratio between the minimum input powers Pi and P 2 required to the reader to remotely activate the two chips placed on the tag. Therefore, the method is advantageously adapted to measure further magnitudes by producing corresponding measurement charts or tabies.
  • step 2 When there is more than one multiple-port tag in the environment, the reader isolates the replies from each multiple-port tag (step 2).
  • the sub-steps or intermediate steps included in step 2 are listed below: - receiving the IDs of the chips defining the different tags existing in the query region (step 2.1);
  • step 2.2 querying the corresponding chip and reading in its memory the ID of all the chips which form the same multiple-port tag (step 2.2); - grouping all the IDs belonging to a same multiple-port tag (step 2.3);
  • step 2.4 - identifying the chips which, despite belonging to a multiple-port tag, are the only ones to receive energy to reply to the reader (step 2.4), then processed in step 3;
  • the target is assumed to be a homogenous dielectric half-space of infinite extension.
  • the curve in Fig. 6 is numerically calculated and loaded on said storage means belonging to the reader, which uses this curve at step 4.3 of the preceding flow chart in Fig. 5.
  • the amplitude of the permittivity range of the target may be distinguished by the reader according to the distance between reader and tag. Such a range is indicated on the curve by the pair of equivalent markers.
  • the entire permittivity range 2.7 ⁇ ⁇ ⁇ 4 may be distinguished up to a maximum distance of 4 meters.
  • a smaller range, i.e. 2.9 ⁇ ⁇ ⁇ 3.45, may instead distinguished up to 5 meters.
  • the reader having queried the target according to the aforesaid procedure, receives two reply signals in such a manner that the ratio between the powers M 12 is 2, the estimated permittivity value ⁇ ta rg et obtained from the curve is equal to 3.3, which may be identified for a distance of up to 6m.
  • the second example relates to a double-port tag applied on a surface of a liquid container (Fig. 10) for monitoring the integrity of the container and, specifically, for determining whether it contains water or a flammable and toxic liquid having the same appearance, e.g. chlorobenzene.
  • the tag with the antenna MLAw Upon the query by the reader, the tag with the antenna MLAw transmits a code IDw 1 while the tag with the antenna MLACB transmits a code IDCB-
  • the matching of the antenna MLA W is better than that of the antenna MLACB, SO that the first antenna will always send its identification, regardless of the type of content of the container or bottle.
  • the reader queries the two-port tag in an appropriate reading distance range, depending on the power emitted by the tag and on the sensitivity of the chip (e.g. in the range between 0.5m and 2m, in the case in which the power emitted by the reader is 3.2W EIRP and the sensitivity of the chip is 10 ⁇ W), said tag will reply only with the code IDw if the bottle contains water, thus simply identifying the code thereof.
  • the second antenna MLA C B will also be activated transmitting back its identification ICB and indicating that the bottle with code IDw has been adulterated.
  • a third example consists in monitoring the filling level of a container.
  • the content is powdered sugar and the container is a 20 cm side cubic box made of plastic material (Perspex) (Fig.11).
  • the multiple-port tag again consists of a pair of facing meander antennas (Fig.12).
  • the plastic container was placed on a 1 m x 1 m size copper sheet which acts as image plane and therefore only half of the antennas needed to be constructed.
  • the power transmission coefficient ⁇ was measured, for the two ports, which represents the proportional share of the power picked up by the single antenna which is absorbed by its chip and, in case of perfect impendence matching, must be unitary.
  • the patterns of T 1 and ⁇ 2 which have been computer simulated and measured in laboratory (Fig.13), show the different matching of the two antennas MLAi and MLA 2 .

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  • Engineering & Computer Science (AREA)
  • Computer Hardware Design (AREA)
  • Microelectronics & Electronic Packaging (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Radar Systems Or Details Thereof (AREA)
  • Developing Agents For Electrophotography (AREA)
  • Surface Acoustic Wave Elements And Circuit Networks Thereof (AREA)
  • Burglar Alarm Systems (AREA)
  • Near-Field Transmission Systems (AREA)

Abstract

La présente invention concerne un RFID à ports multiples comprenant un lecteur qui émet un signal d'interrogation et une ou plusieurs étiquettes multi-ports passives, chacune incluant au moins deux puces connectées à la même antenne ou chacune à une antenne différente, de sorte que l'impédance du port de chaque puce est différente en ce que les caractéristiques du signal de réponse de chaque puce permet de détecter une ou plusieurs magnitudes physiques-chimiques ou géométriques de la cible sur laquelle l'étiquette multi-ports est appliquée, lesdites magnitudes affectant à la fois la réception du signal d'interrogation et l'émission du signal de réponse.
PCT/IB2008/053664 2007-09-11 2008-09-11 Rfid à ports multiples et son procédé de fabrication et d'utilisation WO2009034534A2 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ITRM2007A000466 2007-09-11
ITRM20070466 ITRM20070466A1 (it) 2007-09-11 2007-09-11 Rfid a porta multipla e relativo metodo di realizzazione e di utilizzo

Publications (2)

Publication Number Publication Date
WO2009034534A2 true WO2009034534A2 (fr) 2009-03-19
WO2009034534A3 WO2009034534A3 (fr) 2010-01-07

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Application Number Title Priority Date Filing Date
PCT/IB2008/053664 WO2009034534A2 (fr) 2007-09-11 2008-09-11 Rfid à ports multiples et son procédé de fabrication et d'utilisation

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IT (1) ITRM20070466A1 (fr)
WO (1) WO2009034534A2 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9317726B2 (en) 2012-04-23 2016-04-19 Avery Dennison Corporation Radio frequency identification sensor assembly

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5764138A (en) * 1994-04-29 1998-06-09 Hid Corporation RF identification system for providing static data and one bit of variable data representative of an external stimulus
US5461385A (en) * 1994-04-29 1995-10-24 Hughes Identification Devices, Inc. RF/ID transponder system employing multiple transponders and a sensor switch
US6121880A (en) * 1999-05-27 2000-09-19 Intermec Ip Corp. Sticker transponder for use on glass surface

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9317726B2 (en) 2012-04-23 2016-04-19 Avery Dennison Corporation Radio frequency identification sensor assembly

Also Published As

Publication number Publication date
ITRM20070466A1 (it) 2009-03-12
WO2009034534A3 (fr) 2010-01-07

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