JP5547582B2 - Integrated antenna with hollow contactless IC card antenna - Google Patents

Description

  The present invention relates to an integrated antenna in which an electric field communication antenna and a contactless IC card antenna or RFID antenna are arranged on the same plane.

  Today, payment systems using electronic money using non-contact IC cards (hereinafter referred to as IC cards) and RFID tags that are used at vending machines and cash registers of shops are becoming common.

  For example, the vending machine shown in FIG. 3A or the like is automatically sold by holding the IC card over the antenna circuit 41, the substrate 42 and the noncontact IC card antenna 40 in which the magnetic body 43 is laminated. There has been proposed a technology for performing communication between a machine and an IC card (see, for example, Patent Document 1).

  Further, an electronic payment system for vending machines using electric field communication using a human body as a communication path has been proposed (for example, see Patent Document 2).

  In this electronic settlement system, a customer who possesses an electric field communication device storing electronic money is connected between the metal electrodes 51a and 51b of the electric field communication device mounted in the vending machine shown in FIG. By holding the hand over the electric field communication antenna 50 having a structure in which the dielectric 52 is sandwiched between the electric field communication apparatus and the electric field communication antenna 50 of the vending machine, communication is performed by electrostatic coupling. The payment is made from the stored electronic money.

  In general, commercially available IC cards and RFID tags use a 13.56 MHz frequency band for data communication with the non-contact IC card antenna 40, and proximity communication that ensures compatibility of IC cards and RFID tags. It is used as an interface. The non-contact IC card antenna 40 has an approximate resonance characteristic (Q coefficient) so as to cover a subcarrier frequency band of 13.56 MHz ± 340 KHz including a carrier frequency of 13.56 MHz and a data signal.

  Currently, in consideration of customer convenience, the spread of integrated antennas equipped with both conventional contactless IC card antennas and electric field communication antennas is about to begin.

JP 2004-30393 A JP 2004-145873 A

  However, in order to use both IC card communication and electric field communication, it is necessary to mount a conventional non-contact IC card antenna and electric field communication antenna having different characteristics in a vending machine or the like.

  When the non-contact IC card antenna and the electric field communication antenna are arranged, if they are arranged at different positions in order to maximize the characteristics, there is a problem that the installation surface of the antenna becomes wide.

  In addition, if the non-contact IC card antenna and the electric field communication antenna are arranged at different positions, there is a possibility that the customer may be confused about which one to use, and in order not to impair the convenience of the customer, It is necessary to arrange the contact IC card antenna and the electric field communication antenna at the same position.

  When the non-contact IC card antenna and the electric field communication antenna are disposed at the same position, the electric field communication antenna is simply superimposed on or below the non-contact IC card antenna, or the non-contact IC card antenna is electric field communication. When sandwiched between both electrodes together with the dielectric (insulator) of the antenna for the antenna, the magnetic field generated from the antenna for the contactless IC card is blocked by the metal surface electrode of the antenna for electric field communication, and the antenna for the contactless IC card There is a problem of hindering communication with an IC card or an RFID tag.

  As shown in FIG. 4, when the electric field communication antenna 50 is simply disposed under the conventional non-contact IC card antenna 40, the laminated structure constituting the non-contact IC card antenna 40 is an antenna circuit. A capacitor having a structure in which a substrate 42 and a magnetic body 43 are sandwiched between 41 and an electric field communication antenna 50 metal surface electrode 51a is formed. When the inhibition capacitance C1 of this capacitor enters in series, there is a problem that a heterogeneous layer capacitor is formed in the electric field communication antenna 50 and becomes a communication barrier of the electric field communication antenna 50.

  In general, an existing IC card or RFID tag using 13.56 MHz that is commercially available is used for electric field communication when the non-contact IC card antenna 40 and the electric field communication antenna 50 shown in FIG. 4 are simply arranged at the same position. It is known that the impedance of the non-contact IC card antenna 40 fluctuates due to the influence of the metal surface electrode 51a of the antenna 50, and the peak frequency value of the carrier frequency 13.56 MHz shifts due to the influence of the adjacent metal surface. Yes. Therefore, an IC card or an RFID tag with high Q characteristics has a problem that the resonance frequency fluctuates and the electric field becomes weak, so that power supply is reduced and a necessary electromotive force cannot be obtained, and data communication cannot be performed.

  The present invention has been made paying attention to the above-described problems. The electric field communication antenna and the non-contact IC card antenna are arranged at the same position, and a good communication environment is obtained without hindering mutual communication. An object of the present invention is to provide an integrated antenna using a secured non-contact IC card antenna.

  In order to achieve the above-mentioned object, the present invention has the following configurations (1) and (2).

  (1) An integrated antenna including an electric field communication antenna and a non-contact IC card antenna, wherein the electric field communication antenna has a laminated structure in which a metal surface electrode, a dielectric, and a metal surface electrode are stacked in order. The non-contact IC card antenna has an annular structure in which an antenna portion formed in an annular shape, a substrate formed in an annular shape along the shape of the antenna portion, and an annular magnetic body along the substrate are stacked. And the magnetic body of the non-contact IC card antenna is placed on an upper surface of the metal surface electrode of the electric field communication antenna so that the metal surface can be seen. Integrated antenna by antenna.

  (2) An integrated antenna including an electric field communication antenna and a non-contact IC card antenna, wherein the electric field communication antenna has a laminated structure in which a metal surface electrode, a dielectric, and a metal surface electrode are stacked in this order. The non-contact IC card antenna has an annular structure in which an antenna portion formed in an annular shape, a substrate formed in an annular shape along the shape of the antenna portion, and an annular magnetic body along the substrate are stacked. The magnetic material of the non-contact IC card antenna is placed opposite to the metal surface electrodes on both sides of the electric field communication antenna so that the metal surface can be seen. Integrated antenna with IC card antenna.

  According to the present invention, the non-contact IC card antenna and the electric field communication antenna are arranged at the same position, so that the customer's convenience is not impaired and each antenna is good without interfering with the mutual communication. An integrated antenna using a hollow contactless IC card antenna that ensures a communication environment can be provided.

(A) Configuration diagram of an integrated antenna using a hollow non-contact IC card antenna according to the present invention using a frame-shaped non-contact IC card antenna, (b) Medium according to the present invention using a circular non-contact IC card antenna Configuration diagram of an integrated antenna with a non-contact IC card antenna, (c) AA enlarged sectional view (A) The figure which shows the circuit structure at the time of mounting the antenna for non-contact IC cards in the conventional antenna for electric field communication, (b) The circuit structure of the integrated antenna by the antenna for hollow non-contact IC cards concerning this invention Illustration (A) Configuration diagram of a conventional contactless IC card antenna, (b) Configuration diagram of a conventional electric field communication antenna The perspective view which shows the structure which mounted the conventional antenna for non-contact IC cards on the metal surface upper part of the conventional electric field communication antenna

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

  FIG. 1 is a configuration diagram of an integrated antenna (hereinafter referred to as an integrated antenna) using a hollow non-contact IC card antenna. 1a is a frame-type integrated antenna using a frame-type non-contact IC card antenna 2, and 1b is a circular non-contact antenna. It is a circular integrated antenna using a contact IC card antenna 8.

  A frame-shaped integrated antenna 1a shown in FIG. 1A includes a frame-shaped antenna portion 2a, a substrate 2b, and a magnetic body 2c of a frame-shaped non-contact IC card antenna 2, and metal surface electrodes 7a on both sides of an electric field communication antenna 5. 7b is an integrated antenna which is laminated on the metal surface electrode 7a and in which the central part of the frame-shaped non-contact IC card antenna 2 is cut out in an annular shape along the antenna formation width to form a hollow hole H. As the magnetic body 2c placed on the metal surface of the metal surface electrode 7a, one having a relative permeability of 100 or more is used in order to secure a magnetic path of the magnetic field M generated by the frame-type non-contact IC card antenna 2.

  In the circular integrated antenna 1b shown in FIG. 1B, a circular antenna portion 8a, a substrate 8b, and a magnetic body 8c of a circular non-contact IC card antenna 8 are laminated on the metal surface electrode 7a of the electric field communication antenna 5. This is an annular integrated antenna in which a hollow hole H is formed by hollowing out the central portion to avoid the formation width of the antenna.

  The function of the integrated antenna according to the present embodiment will be described with reference to the AA cross-sectional view of the frame-shaped integrated antenna 1a shown in FIG. 1C. The frame-shaped integrated antenna formed on the metal surface electrode 7a of the electric field communication antenna 5 will be described. The contact IC card antenna 2 has a hollow hole H formed by cutting the peripheral and central substrate 2b and the magnetic body 2c along the formation width of the frame-shaped antenna part 2a, and the hollow hole H and the frame-shaped antenna part 2a. It is possible to have a structure in which the metal surface electrode 7a of the electric field communication antenna 5 is exposed in a wide range in the portion around the periphery.

  When the customer who owns the device for electric field communication holds his hand over the integrated antenna, the frame-shaped non-contact IC card antenna 2 avoids communication obstruction caused by the metal surface of the metal surface electrode 7a being insulated. By obtaining the strength of the electric field E necessary for communication with the communication antenna 5, it is possible to ensure good communication sensitivity.

  In the conventional integrated antenna shown in FIG. 4 as the antenna circuit, when the customer holds his / her hand over the integrated antenna, the mounting area S1 of the conventional non-contact IC card antenna 40 is equal to the antenna circuit 41 and the electrode 51. In the meantime, a fault capacitor C1 applied in series is generated by a capacitor formed by sandwiching the dielectric of the substrate 41 and the magnetic body 43, and there is a problem that the communication of the electric field communication antenna 50 is hindered.

  That is, the connection between the conventional electric field communication antenna 50 and the non-contact IC card antenna 40 is caused by the fault capacitance C1 generated by the capacitor formed by the conventional non-contact IC card antenna 40 as shown in FIG. Since the capacitor C2 of the electric field communication antenna 50 is connected in series, the capacitor C2 of the electric field communication antenna 50 changes its impedance when the customer holds his / her hand, and the electric field strength required for electric field communication. Fluctuates.

  Further, the capacitance C of the parallel plate capacitor is obtained by a value C = εS / L obtained by multiplying the area S of the electric field antenna by the dielectric constant ε of the dielectric and the distance L between the electrodes. The surface area S of the electrode is important. Therefore, the strength of the electric field E necessary for communication is such that when the mounting area S1 of the conventional non-contact IC card antenna 40 becomes wide, the obstacle area increases and obstructs the communication of the electric field communication antenna 50. Since the required electric field strength cannot be ensured, the sensitivity of the electric field communication antenna 50 decreases.

  However, in the integrated antenna of the present embodiment, due to the annular structure of the non-contact IC card antenna 2, only the region where the frame-like antenna portion 2 a is formed is an exposed region of the metal surface electrode 7 a of the electric field communication antenna 5. Since the area directly touched by the human body is greatly enlarged and the formation width of the frame-like antenna portion 2a is made as narrow as possible, the fault capacitance C1 generated by the non-contact IC card antenna 2 can be ignored ( C4 >> C1), the fluctuation of the electric field intensity due to the change of the synthetic impedance is slight, and the area occupied on the metal surface of the metal surface electrode 7a is reduced, and the sensitivity of the electric field communication antenna 5 is not affected.

  Therefore, in the integrated antenna of this embodiment, the circuit connection between the capacitor C3 of the non-contact IC card antenna 2 using the magnetic field M and the capacitor C4 of the electric field communication antenna 5 using the electric field E is shown in FIG. As shown in FIG. 2, each of them can have an independent circuit configuration. The capacitor C4 of the electric field communication antenna 5 has a structure in which the metal surface electrode 7 of the electric field communication antenna 5 is exposed in a wide range when the customer who owns the electric field communication device holds his hand, and the electric field necessary for communication Since E is sufficiently secured, electric field communication is not affected.

  Next, the function of the hollow contactless IC card antenna is such that, for example, in the case of the frame-shaped contactless IC card antenna 2, the IC card is mounted on the upper surface of the metal surface electrode 7 of the electric field communication antenna 5. It is necessary to make the structure unaffected by the electric field communication antenna 5 when approaching.

  However, when the frame-shaped non-contact IC card antenna 2 is placed on the metal surface electrode 7a of the electric field communication antenna 5, an eddy current is generated due to the image effect of the metal surface, and a reverse-phase magnetic field is generated. There is a problem in that the magnetic field M of the contact IC card antenna 2 is canceled and shielded.

  In this embodiment, when the IC card is held over the frame-shaped antenna portion 2a formed on the substrate 2b, the transparent non-contact IC card antenna 2 shown in FIG. By laminating magnetic bodies 2c having magnetic tensities of several tens to several hundreds, a magnetic path of a magnetic field generated in the frame antenna portion 2a is secured, and a stable magnetic field is generated without shielding the magnetic field on the metal surface electrode 7a. Thus, a structure that suppresses the influence of the metal surface electrode 7a is provided, and sufficient electromotive force due to electromagnetic induction of the IC card is sufficiently ensured to enable good data communication.

  In addition, since many kinds of sheet-like magnetic materials having various thicknesses and magnetic permeability are commercially available, the type of the magnetic body 2c laminated on the frame-shaped antenna portion 2a should be selected according to the application. However, the present embodiment is not limited.

  Further, with respect to the problem that the impedance of the non-contact IC card antenna 2 fluctuates due to the influence of the adjacent metal surface electrode 7a shown in FIG. In the tag, the electromotive force due to electromagnetic induction cannot be obtained due to the deviation of the resonance frequency. Alternatively, even if an electromotive force is obtained, the effective power is greatly reduced, so that the approach distance between the IC card or RFID tag and the non-contact IC card antenna 2 is limited to a narrow range, or the frequency band of data communication is out of range. May cause an error in data communication.

  In order to avoid the phenomenon of frequency shift due to the influence of the metal surface, the impedance of the matching circuit of the frame-shaped non-contact IC card antenna 2 is set in advance to a value that takes into account the influence of the metal surface electrode 7a. It is possible to provide a characteristic in which the bandwidth required for communication is widened by suppressing the Q characteristic value of 2a. As a result, by forming the frame-shaped non-contact IC card antenna 2 having a Q characteristic having a wide resonance frequency bandwidth capable of supplying effective power without reducing the electric field strength, the electric field communication antenna 5 The integrated antenna corresponding to the frequency shift which is the influence of the metal surface electrode 7a can be provided.

  Furthermore, in order to prevent an eddy current generated by the image effect of the metal surface electrode 7a of the electric field communication antenna 5, the metal surface electrode 7a is divided into two horizontal plates at the center, and the two horizontal plates are formed. Provided is an integrated antenna that is configured to prevent generation of eddy currents by connecting the frame-shaped non-contact IC card antenna 2 so as to straddle the metal surface electrodes 7a of the two horizontal plates, connected by conducting wires. be able to.

  In addition, the impedance of the antenna matching circuit of the non-contact IC card antenna is set to a value in consideration of the influence of the metal surface electrode 7a in advance, and the bandwidth is widened by suppressing the Q characteristic value of the frame-shaped antenna portion 2a. By forming the frame-shaped non-contact IC card antenna 2 having the Q characteristic of the resonance frequency bandwidth capable of supplying effective power without lowering the induced electromotive force of the IC card or the RFID tag, for electric field communication The integrated antenna corresponding to the frequency shift which is the influence of the metal surface electrode 7a of the antenna 5 can be provided.

  The integrated antenna of this embodiment has been described with a configuration in which a hollow non-contact IC card antenna is formed on one side of a metal surface electrode of an electric field communication antenna for the purpose of mounting in a vending machine or the like. When installing the integrated antenna of this embodiment on a glass door with an auto-lock mechanism for opening and closing the door, electric field communication is performed in the hole for the authentication device on which the door is formed. The authentication device can be accessed from both sides of the door by attaching integrated antennas having hollow non-contact IC card antennas formed on the metal surfaces 7a and 7b on both sides of the antenna 5 for use.

  Or use glass door structure, use glass as dielectric for electric field communication antenna and install integrated antenna with hollow contactless IC card antenna and electric field communication antenna on both sides of glass door Is also possible.

  In addition, the integrated antenna of this example is formed by forming an antenna pattern and a metal surface electrode into a film by depositing an electric field communication antenna and a hollow contactless IC card antenna on a resin, and laminating them. By creating an integrated integrated antenna, it is possible to make an integrated antenna with a laminated structure of a thin and flexible sheet material that can be installed on a curved surface.

DESCRIPTION OF SYMBOLS 1a Frame-shaped integrated antenna 1b Circular integrated antenna 2 Frame-shaped non-contact IC card antenna 2a Frame-shaped antenna part 2b Substrate 2c Magnetic body 5 Electric field communication antenna 6 Dielectric 7 Metal surface electrode 8 Circular non-contact IC card antenna 8a Circular antenna section 8b Substrate 8c Magnetic body 40 Non-contact IC card antenna 41 Antenna portion 42 Substrate 43 Magnetic body 50 Electric field communication antenna 51 Electrode 52 Dielectric C1 Inhibition capacitance E Electric field M Magnetic field H Hollow hole

Claims (2)

An integrated antenna comprising an electric field communication antenna and a non-contact IC card antenna,
The electric field communication antenna has a laminated structure in which a metal surface electrode, a dielectric, and a metal surface electrode are stacked in order,
The non-contact IC card antenna has an annular structure in which an antenna portion formed in an annular shape, a substrate formed in an annular shape along the shape of the antenna portion, and an annular magnetic body along the substrate are stacked Have
According to the hollow contactless IC card antenna, wherein the magnetic body of the contactless IC card antenna is placed on an upper surface of the metal surface electrode of the electric field communication antenna so that the metal surface can be seen. Integrated antenna. An integrated antenna comprising an electric field communication antenna and a non-contact IC card antenna,
The electric field communication antenna has a laminated structure in which a metal surface electrode, a dielectric, and a metal surface electrode are stacked in order,
The non-contact IC card antenna has an annular structure in which an antenna portion formed in an annular shape, a substrate formed in an annular shape along the shape of the antenna portion, and an annular magnetic body along the substrate are stacked Have
The hollow non-contact IC card, wherein the magnetic body of the non-contact IC card antenna is placed facing the metal surface electrodes on both sides of the electric field communication antenna so that the metal surface can be seen. Integrated antenna with an antenna.

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