JP2012108843A - Rfid tag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an RFID tag which can satisfy demand characteristics such as communicability with a plurality of frequency regions, compactness, high reliability with a suppressed communication failure, and high memory performance.SOLUTION: In an RFID tag compatible with a UHF band frequency, a plurality of IC chip modules comprising an IC chip and a loop conductor, constituting the RFID tag, are included. The loop conductor is electrically or electromagnetically coupled with one booster antenna comprising a dipole antenna or a loop antenna, and communications with the plurality of IC chips can be achieved via the booster antenna.

Description

  The present invention relates to an RFID tag to which a frequency in the UHF band (800 to 1000 MHz) is applied. Particularly, a plurality of IC chips are electrically and electromagnetically connected to one transmission / reception antenna, thereby increasing storage capacity. The present invention relates to an RFID tag that is improved in reliability and multi-functional.

  An RFID tag is integrally mounted with a communication chip body and an antenna suitable for the operating frequency. As a result, the IC chip antenna receives radio waves from an external reader / writer and supplies operating power to the chip body, thereby realizing necessary data communication between the chip body and the reader / writer. it can. Note that the communication method and frequency used for the IC chip are appropriately selected according to the intended use and the required information transmission distance.

  An RFID tag incorporates an antenna and an IC chip. In general, a single IC chip for communication is incorporated, the mounting function is limited, and the antenna of the IC chip is extremely small, so that sufficient transmission / reception sensitivity cannot be obtained, There was a problem that the information transmission distance was insufficient.

  Therefore, a plurality of IC chips having the same operating frequency and having an antenna integrally mounted on the chip body, and a booster coil that is provided with a resonance capacitor and operates as a common external antenna of the IC chip are provided on the card substrate. The booster coil is mounted in a two-dimensional spiral shape with a plurality of turns to form a maximum opening area within the effective area of the card base, and for at least two IC chip antennas. It is proposed that electromagnetic coupling is performed through individual surrounding portions formed in the booster coil by the total number of turns, and the surrounding portions are formed on the card substrate with the same line spacing as the booster coil.

  However, the booster coil needs to be provided for each IC chip with a booster coil portion for tightly coupling with each IC chip module, and there is a problem that the coil wiring becomes complicated. Moreover, the frequency of the signal applied in order to communicate is 13.56 MHz single, and it is not considered about the response | compatibility to communication and communication performance in a several frequency area | region (patent document 1).

Japanese Patent No. 4370601

  In view of the problems of the prior art, the object of the present invention is to respond to each required characteristic such as being capable of communication in a plurality of frequency regions, being small in size, being able to suppress communication failure, and having high reliability and high memory performance. It is to provide an RFID tag that can be used.

As means for solving the above-mentioned problem, the invention according to claim 1 is the RFID tag adapted to the frequency of the UHF band. The loop conductor is electrically (including electromagnetically) coupled to a booster antenna composed of a dipole antenna or a loop antenna, thereby enabling communication with a plurality of IC chips via the booster antenna. The RFID tag is characterized.

  The invention according to claim 2 is characterized in that an external shape of the booster antenna is a rectangle, and is symmetrical with respect to a midpoint or a center line of the long side of the rectangle. It is an RFID tag as described in above.

  According to a third aspect of the present invention, the plurality of IC chip modules have the same outer shape, and the mounting position of the IC chip on the IC chip module is symmetrical with respect to the outer shape of the IC chip module. The RFID tag according to claim 1, wherein the communication performance of the plurality of mounted IC chips is made equal, the storage capacity is increased, and the reliability is improved.

  Further, in the invention according to claim 4, the mounting positions of the IC chips of the plurality of IC chip modules and the arrangement of the plurality of IC chip modules in the RFID tag are symmetric with respect to the center position of the RFID tag outer shape. The RFID tag according to any one of claims 1 to 3, wherein a plurality of mounted IC chips have the same communication performance, and an increase in storage capacity and reliability are improved.

  According to a fifth aspect of the present invention, the plurality of IC chip modules are arranged asymmetrically with respect to a center line perpendicular to the long side of the outer shape of the booster antenna. The RFID tag according to claim 1, wherein each is read and written independently.

  According to a sixth aspect of the present invention, there is provided a plurality of IC chips in which the arrangement of the plurality of IC chip modules is partially or entirely asymmetrical and the shape of the loop conductor of the IC chip module is partially or entirely changed. The RFID tag according to claim 1 or 5, wherein each is read and written independently.

  In the invention according to claim 7, the IC chip module is formed on a substrate different from the booster antenna, and the substrate on which the IC chip module is formed has the booster antenna The RFID tag according to any one of claims 1 to 6, wherein the RFID tag is attached to a formed substrate.

  The invention according to claim 8 is characterized in that, when the booster antenna is a loop antenna, at least one of the plurality of IC chip modules is mounted outside the loop of the booster antenna. The RFID tag according to any one of claims 1 to 7.

  In the invention according to claim 9, the plurality of IC chip modules are formed on the same base material as the booster antenna, and the base material has a roll shape, and the booster antenna has the roll base shape. The IC chip module mounting positions of the IC chip modules on the roll substrate are continuously arranged at regular intervals in the longitudinal direction of the material. The RFID tag according to any one of claims 1 to 6, wherein the RFID tag is arranged in a mechanical manner.

The present invention enables communication with a plurality of IC chips via a common booster antenna, and by sharing the functions among the IC chips, the memory capacity is increased and a different password lock is applied to each IC chip. A plurality of users having individual passwords can communicate exclusively with individual IC chips without any other data being read.

1 is a conceptual diagram showing an IC chip module 3 composed of an IC chip 1 and a loop-shaped conductor 2. FIG. It is the conceptual diagram which showed the RFID tag 11 which consists of the dipole type | mold booster antenna 4 and IC chip module 3 of this invention. The conceptual diagram which showed the RFID tag 11 which consists of the loop type | mold booster antenna 5 and IC chip module 3 of this invention. It is the conceptual diagram which showed the center 6 and centerline 7 of each of the dipole type | mold and loop type | mold booster antenna of this invention. 3 is a conceptual diagram showing a state where the mounting position of the IC chip 1 is at the center line 7 of the IC chip module 3. FIG. FIG. 3 is a conceptual diagram showing a state in which the mounting position of the IC chip 1 of the present invention is shifted from the center line 7 of the IC chip module 3 but mounted in a symmetrical position with respect to the center line 7 of the RFID tag 11. . FIG. 3 is a conceptual diagram showing a state where the IC chip module 3 and the dipole booster antenna 4 of the present invention are arranged in a symmetrical position with respect to the center line 7 of the RFID tag 11. FIG. 3 is a conceptual diagram showing a state in which the IC chip module 3 and the loop booster antenna 5 of the present invention are arranged at symmetrical positions with respect to the center line 7 of the RFID tag 11. FIG. 3 is a conceptual diagram showing a state where the IC chip module 3 and the dipole booster antenna 4 of the present invention are arranged in a symmetrical position with respect to the center line 7 of the RFID tag 11. FIG. 3 is a conceptual diagram showing a state in which the IC chip module 3 and the dipole booster antenna 4 of the present invention are arranged at symmetrical positions with respect to the center 6 of the RFID tag 11. FIG. 3 is a conceptual diagram showing a state in which the IC chip module 3 of the present invention is disposed at an asymmetric position with respect to the center line 7 of the RFID tag 11. It is the conceptual diagram which showed the state by which the IC chip module of this invention is arrange | positioned in the asymmetrical position with respect to the centerline of RFID tag. FIG. 3 is a conceptual diagram showing a state in which the IC chip module 3 of the present invention is disposed at asymmetric positions with respect to the center line 7 and the center 6 of the RFID tag 11. It is a conceptual diagram which shows the shape from which the shape of the loop-shaped conductor 2 in the some IC chip module 3 mounted in the dipole type | mold booster antenna 4 of this invention is one part, or all differ. It is a conceptual diagram which shows the shape from which the shape of the loop-shaped conductor 2 in the some IC chip module 3 mounted in the loop type | mold booster antenna 5 of this invention is one part, or all differ. It is a conceptual diagram which shows the shape from which the shape of the loop-shaped conductor 2 in the some IC chip module 3 mounted in the dipole type | mold booster antenna 4 of this invention is one part, or all differ. It is the conceptual diagram which showed the shape of the RFID tag 11 manufactured by affixing the IC chip module base material of this invention on a booster antenna base material. It is the conceptual diagram which showed the shape of the RFID tag 11 which has arrange | positioned the IC chip module 3 and the dipole type | mold booster antenna 4 of this invention continuously with a fixed space | interval in the longitudinal direction of the roll-shaped base material. It is the conceptual diagram which showed the shape of the RFID tag 11 which has arrange | positioned the IC chip module 3 and the dipole type | mold booster antenna 4 of this invention continuously with a fixed space | interval in the longitudinal direction of the roll-shaped base material. It is the conceptual diagram which showed the state by which all the several IC chip modules 3 arrange | positioned at the loop type booster antenna 5 of this invention were arrange | positioned outside the loop of the booster antenna. FIG. 4 is a conceptual diagram showing a state in which at least one of a plurality of IC chip modules 3 arranged in the loop booster antenna 5 of the present invention is arranged inside the loop of the booster antenna, and the other IC chip modules 3 are arranged outside. . The external view which showed arrangement | positioning of the dipole type | mold booster antenna 4 and the IC chip module 3 which were formed on the base material of Example 1 of this invention. The characteristic view which showed the relationship between the frequency and impedance of Embodiment 1 of this invention. The external view which showed arrangement | positioning of the dipole type | mold booster antenna 4 and IC chip module 3 which were formed on the base material of Example 2 of this invention. The characteristic view which showed the relationship of the frequency and impedance of arrangement | positioning of the dipole type | mold booster antenna 4 and IC chip module 3 which were formed on the base material of this invention Embodiment 2. FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.

  FIG. 1 shows an IC chip module 3 in which an IC chip 1 is mounted on a loop conductor 2.

  FIG. 2 shows a state where a plurality of IC chip modules 3 are electrically coupled to the dipole booster antenna 4, and FIG. 3 illustrates a state where the plurality of IC chip modules 3 are electrically coupled to the loop booster antenna 5. Yes.

  FIG. 4 shows the center 6 and the center line 7 of the dipole booster antenna 4 and the loop booster antenna 5, respectively. The outer shape of the booster antenna is close to a rectangle, and the line segment connecting the midpoints of the long sides or the outer shape. The antenna is substantially symmetrical with respect to the shape center 6.

  FIG. 5 shows a state where the mounting position of the IC chip 1 is at the center line of the IC chip module 3, and FIG. 6 shows the mounting position of the IC chip 1 relative to the center line 7 between the IC chip modules of the RFID tag 11. This shows a state where they are arranged at symmetrical positions. Similarly, in FIGS. 7, 8, 9 and 10, at least the outer shape of the IC chip module 3 is equal, and the mounting position of the IC chip 1 in the IC chip module 3 is a symmetrical center with respect to the outer shape of the IC chip module 3. The external shape of each IC chip module 3 and the mounting position of the IC chip 1 are symmetrical. Therefore, the communication performance (communication distance) of the IC chip 3 is almost the same, and it is optimal for applications requiring a communication balance between the IC chips 1 such as the purpose of memory expansion and exclusive reading by a plurality of users.

11, 12, and 13 show a state where the arrangement of the IC chip module 3 is asymmetric with respect to the center line of the long side in the outer shape of the dipole booster antenna 4 and the loop booster antenna 5. The dipole booster antenna 4 and the IC chip module 3 in FIGS. 11 and 13 are electrically coupled.
<Embodiment 1>
FIG. 22 shows that the center line 7 and the dipole booster antenna are mounted in order to mount the two IC chip modules 3 asymmetrically with respect to the center line vertically passing through the long side of the outer shape of the dipole booster antenna 4. By changing the distance from 4, each IC chip module 3 can be read and written independently. The simulation was performed on the RFID tag 11 in which the IC chip 1 was electrically connected to the IC mounting portion 1A and the IC mounting portion 2B to the common dipole booster antenna 4.

  The relationship between the frequency and impedance of the RFID tag 11 was obtained by simulation. The simulation result is shown in FIG. 23, and the communication distance between the IC chips mounted on the IC mounting unit 1A and the IC mounting unit 2B is shown in Table 1.

The communication distances at 953 MHz are 1.5 m and 5.0 m, respectively, and it can be seen that only the IC chip 1 mounted on the IC mounting unit 2B can be read when reading from a distance.

  Thus, by adjusting so that only one of the plurality of IC chips 1 can be read, even if the RFID tag 11 having the same booster antenna and the plurality of IC chips 1 is crowded, the communication can be performed. It becomes easy to read the individual RFID tags 11 collectively from a distant place without causing a failure.

  Further, the same effect can be obtained when the RFID tag 11 is read and read close to the antenna for writing. By applying different password locks for individual IC chips, a plurality of users having individual passwords can communicate exclusively with the individual IC chips without any other data being read. In particular, the antenna structure is effective when the radiating element is close to a metal body other than the radiating element with a dielectric interposed therebetween.

14, 15, and 16 show the shapes of the loop-shaped conductors in the plurality of IC chip modules 3 mounted on the dipole type 4 or loop type booster antenna 5, which are partially or entirely different.
<Embodiment 2>
FIG. 24 shows an RFID tag in which mounting of two IC chip modules 3 is asymmetrical and the shape of the loop conductor 2 of the IC chip module 3 is changed so that a plurality of IC chips can be read and written independently. 11. The frequency that can be communicated with two IC chips 1 electrically connected to a common booster antenna is adjusted to 953 MHz (Japan) and 867 MHz (Europe) so that only the IC chip 1 corresponding to each frequency can be read. .

  The relationship between the frequency and impedance of the RFID tag 11 was simulated. FIG. 25 shows the simulation result, and Table 2 shows the communication distance of the IC chip mounted on the IC mounting unit 3C (953 MHz) and the IC mounting unit 4D (867 MHz).

The communication distance at each frequency of 953 MHz (Japan) and 867 MHz (Europe) is 6.7 m at 953 MHz for the IC mounting unit 3C, whereas the communication distance is short at 1.3 m for the IC mounting unit 4D, and conversely at 867 MHz. It can be seen that the communication distance is as long as 1.7 m and 5.8 m.

  The RFID tag 11 is particularly effective for an antenna structure in which a radiating element is close to a metal body other than the radiating element with a dielectric interposed therebetween.

  FIG. 17 shows an RFID tag 11 formed by attaching the IC chip module 3 formed on another substrate to a booster antenna formed on another substrate. This makes it easy to change the position of the IC chip module 3 with respect to the booster antenna and to change the IC chip module 3 to be applied, and to easily change / correct the characteristics of the RFID tag 11.

18 and 19, the IC chip module 3 is formed on the same roll-shaped substrate as the booster antenna, and the booster antenna is continuously arranged at a predetermined interval in the longitudinal direction of the roll-shaped substrate. The individual IC chip 1 mounting positions are also continuously arranged at regular intervals in the longitudinal direction of the roll-shaped substrate. This makes it possible to mount the IC chip 1 at equal intervals, and mount the IC chip 1 using a mounting machine having a single mounting head or a mounting machine in which a plurality of mounting heads are aligned at equal intervals. Becomes easy. In particular, when the mounting position of the IC chip 1 is always constant with respect to the width direction of the roll, the IC chip can be sent without moving the mounting head greatly in the surface direction by sequentially feeding the roll by the arrangement interval of the IC chip mounting portions. 1 can be continuously mounted, and work efficiency is improved.

  FIG. 20 shows a form in which all the IC chip modules 3 are mounted outside the loop of the booster antenna when the booster antenna is a loop antenna. Thereby, since the magnetic flux of the booster antenna and the magnetic flux of the IC chip module 3 do not cancel each other, the communication distance can be greatly extended as compared with the case where the IC chip module 3 is mounted inside the loop-shaped booster antenna.

  FIG. 21 shows a form in which at least one of the IC chip modules 3 is mounted outside the loop of the booster antenna. Since the communication distance of the IC chip module 3 mounted inside the loop-shaped booster antenna can be reduced as compared with other modules, it is possible to adjust so that only one of the plurality of IC chips 1 is difficult to read. It becomes possible.

DESCRIPTION OF SYMBOLS 1 ... IC chip 2 ... Loop-shaped conductor 3 ... IC chip module 4 ... Booster antenna (dipole)
5 ... Booster antenna (loop)
6 ... Center 7 ... Center line 8 ... Booster antenna substrate 9 ... IC chip module substrate 10 ... Roll longitudinal direction 11 ... RFID tag A ... IC mounting part 1
B ... IC mounting part 2
C ... IC mounting part 3
D: IC mounting part 4

Claims (9)

  In an RFID tag that conforms to a frequency in the UHF band, a plurality of IC chip modules including an IC chip and a loop conductor constituting the RFID tag are mounted, and the loop conductor is electrically connected to one booster antenna including a dipole antenna or a loop antenna. An RFID tag characterized in that it can be connected to a plurality of IC chips through the booster antenna by being coupled to each other mechanically or electromagnetically.   2. The RFID tag according to claim 1, wherein an external shape of the booster antenna is a rectangle and is symmetrical with respect to a midpoint or a center line of a long side of the rectangle.   The plurality of IC chip modules have the same outer shape, and the mounting position of the IC chip on the IC chip module is symmetric with respect to the outer shape of the IC chip module, so that the communication performance of the plurality of mounted IC chips is equivalent. The RFID tag according to claim 1, wherein an increase in storage capacity and reliability are improved.   The mounting performance of the plurality of mounted IC chips is equalized with the mounting positions of the IC chips with respect to the plurality of IC chip modules and the mounting of the plurality of IC chip modules in the RFID tag being symmetrical with respect to the center position of the outer shape of the RFID tag. The RFID tag according to claim 1, wherein an increase in storage capacity and reliability are improved.   The mounting of the plurality of IC chip modules is mounted asymmetrically with respect to the center line passing vertically through the long side of the external shape of the booster antenna, and the plurality of IC chips are independently read and written. The RFID tag according to claim 1, wherein:   The mounting of the plurality of IC chip modules is partially or entirely asymmetrical, and the shape of the loop conductor of the IC chip module is partially or completely changed to allow the plurality of IC chips to be read and written independently. The RFID tag according to claim 1 or 5, wherein   The IC chip module is formed on a substrate different from the booster antenna, and the substrate on which the IC chip module is formed is attached to the substrate on which the booster antenna is formed. The RFID tag according to any one of claims 1 to 6, wherein:   8. The booster antenna according to claim 1, wherein when the booster antenna is a loop antenna, at least one of the plurality of IC chip modules is mounted outside the loop of the booster antenna. The described RFID tag.   The plurality of IC chip modules are formed on the same base material as the booster antenna, and the base material is in a roll shape, and the booster antenna is continuous at a constant interval in the longitudinal direction of the roll-like base material. The IC chip mounting positions with respect to the IC chip module on the roll-shaped substrate are continuously mounted at a predetermined interval in the longitudinal direction of the roll-shaped substrate. The RFID tag according to any one of claims 1 to 6.