JP2010147913A - Short-range wireless communication terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a structure in which communication performance can be improved when using a short-range wireless communication terminal functioning as RFID even if it is located close to a card reader in any direction. <P>SOLUTION: First and second magnetic material sheets 21, 22 are located on both surfaces of a holding member 11 which holds a coil antenna 12 in a planar shape. The first magnetic material sheet 21 is located to cover a portion of a region where the coil antenna 12 is held on one surface of the holding member 11. The second magnetic material sheet 22 is located to cover a portion of a region where the coil antenna 12 is held on the other surface of the holding member 11 so that the covered region does not overlap with the region covered by the first magnetic material sheet 21. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a short-range wireless communication terminal having a short-range wireless communication function called a non-contact type IC card or IC tag.

  In recent years, the use of non-contact type IC cards is rapidly spreading as transportation tickets, membership cards, employee cards, cards for payment methods in stores, and the like. Non-contact type IC card performs authentication processing by performing wireless communication with a nearby reader / writer, so it can be used in a wallet, pass case, etc., and is easier to use than a magnetic card. Is good.

  In addition, such a non-contact type IC card (or a circuit component having the same function as the IC card) is built in a portable electronic device such as a mobile phone terminal, Those that can be used for authentication and settlement have also been put into practical use. Note that when an IC card function unit is incorporated in a mobile terminal, the IC card function unit is not necessarily in the shape of a card. However, in the following description, an IC card is particularly described when referred to as an IC card. Unless otherwise specified, it includes a portion having an IC card function. In addition, this type of contactless IC card is also referred to as RFID (Radio Frequency Identification), a wireless IC tag, or the like. Although various shapes other than the mold are assumed, in this specification, they are referred to as an IC card for convenience. In addition, a functional unit such as a chip circuit or an antenna constituting the non-contact IC card is referred to as an RFID functional unit.

  When the RFID function unit performs wireless communication with the reader / writer, the RFID function unit is activated by electromagnetic induction from the reader / writer. That is, on the IC card side, a process of tuning to a carrier wave of a predetermined frequency output from the reader / writer is performed, and the detected carrier wave is modulated by ASK (Amplitude shift keying) modulation or the like, and the reader / writer side I am trying to send data. ASK modulation is amplitude modulation that represents a digital signal by a difference in amplitude of a carrier wave.

  FIG. 6 is a diagram showing an outline of the communication state between the reader / writer and the IC card. As shown in this figure, the reader / writer 1 includes a loop antenna 2 and transmits a carrier wave F1 (x) having a predetermined frequency. The IC card 3 also includes a loop antenna 4 and transmits a response waveform F2 (x) ASK-modulated by the loop antenna 4. The loop antenna 2 of the reader / writer 1 receives the carrier wave F1 (x) and the response waveform F2 ( The composite wave of x) is received.

  One way of using such an IC card is called a smart poster. FIG. 7 is a diagram showing an example of use of this smart poster. The IC card 3 is installed on the edge or side of the poster 5 posted at an outdoor station or the like. Then, the reader / writer 1 possessed by the user who viewed the poster 5 is brought close to the IC card 3 to perform wireless communication, and information prepared in the IC card 3 is wirelessly transferred to the reader / writer 1. The reader / writer 1 possessed by the user is assumed to be a reader / writer built in an electronic terminal such as a mobile phone terminal.

  By preparing such a smart poster, information related to the posted poster can be sent to the reader / writer possessed by the user. For example, you can write information about the store on the poster, and deliver detailed information about the store to the reader / writer, such as a detailed map and opening hours. If a reader / writer that can easily distribute the information is built in the mobile phone terminal, the received information can be displayed on the display panel of the mobile phone terminal. In the case of a single reader / writer without a display panel, it is possible to read the distributed information by connecting to a personal computer device or the like possessed by the user.

Patent Document 1 discloses an example of a non-contact type IC card.
JP 2008-131116 A

  When the RFID function unit of the IC card performs wireless communication with the reader / writer, as described above, it operates by electromagnetic induction from the reader / writer. By setting the communication circuit unit as close as possible, wireless communication can be performed correctly. However, since wireless communication is used, when a metal plate is present close to the IC card, communication may not be performed correctly even when the RFID function unit and the reader / writer are close to each other.

As a technique for improving the wireless communication state between the RFID function unit and the reader / writer in such a case, a technique for arranging a magnetic material sheet close to an IC card is known (see Patent Document 1).
Here, with reference to FIG. 8, it will be described that the wireless communication state between the reader / writer and the IC card is improved by the magnetic material sheet. FIG. 8 is a cross-sectional view of the antenna on the IC card side and the antenna on the reader / writer side.
FIG. 8A is a diagram showing a magnetic flux loop when the reader / writer 1 and the IC card 3 are close to each other. The example of FIG. 8A is an example of a normal communication state, in which there is no metal plate or magnetic sheet.

  As shown in FIG. 8A, a magnetic flux loop is generated by the coil antenna 2 of the reader / writer 1. The magnetic flux loop reaches the coil antenna 4 of the IC card 3 and penetrates the IC card 3, so that the coil antenna 4 can receive a signal from the reader / writer 1.

FIG. 8B shows an example where the metal plate 6 is near the IC card 3.
In this case, a magnetic field due to eddy current is generated on the IC card 3 side, and the magnetic flux loop generated by the coil antenna 2 of the reader / writer 1 does not reach the coil antenna 4 of the IC card 3. That is, as shown as a non-penetrating magnetic flux loop in the figure, the magnetic flux loop does not penetrate the IC card 3, and wireless communication is hindered. Therefore, in the state shown in FIG. 8B, wireless communication cannot be normally performed due to the influence of the metal plate 6.

  FIG. 8C shows a state in which the magnetic material sheet 7 is bonded to the IC card 3 and then brought close to the metal plate 6. In this state, the metal plate 6 is close in the same way as in the example of FIG. 8B, but the magnetic material sheet 7 is bonded to the IC card 3. For this reason, the magnetic flux comes to pass through the magnetic material sheet 7, and the magnetic flux loop penetrates the periphery of the coil antenna 4 of the IC card 3. Therefore, as shown in FIG. 8C, the magnetic material sheet 7 is provided on the back surface of the IC card 3 (the back surface here is the surface opposite to the surface close to the reader / writer 1). Even in the proximity of each other, good wireless communication is possible.

As described above, it is known that the wireless communication state between the reader / writer and the IC card can be improved by sticking the magnetic material sheet on one side of the IC card or arranging the magnetic material sheet on one side of the card case.
However, the magnetic material sheet is effective only when the magnetic material sheet is on the back side, that is, the surface close to the reader / writer 1 is on the opposite surface.
That is, as shown in FIG. 9, when the magnetic material sheet 7 arranged on one side of the IC card 3 is a surface facing the reader / writer 1, the magnetic flux loop from the coil antenna 2 of the reader / writer 1 is The magnetic material sheet 7 is returned to the coil antenna 2 side, so that the magnetic flux loop does not reach the coil antenna 4 on the surface opposite to the magnetic material sheet 7. Therefore, when the IC card 3 is directed in a certain direction as shown in FIG. 8 (c), the wireless communication state is improved. However, when the IC card 3 is directed in the opposite direction as shown in FIG. The wireless communication is not possible.

  In this way, the direction of the card capable of short-range wireless communication has a directionality. When using an IC card on a daily basis, it is necessary to always pay attention to the direction and bring it close to the IC card. There was a problem that was not good. For example, when an IC card used as a smart poster as shown in FIG. 7 is installed and there is a metal plate close to the IC card (for example, when the poster is attached to the metal plate), the magnetic card Even if you try to improve the communication performance with the material sheet, if you do not pay attention to the orientation of the magnetic material sheet on the IC card, you will not only be able to improve the communication performance, but also cause the wireless communication performance to deteriorate is there.

  The present invention has been made in view of such points, and when a short-range wireless communication terminal that functions as an RFID is prepared, communication performance is improved regardless of the direction of proximity to the card reader in any direction. The object is to provide a structure that can be used.

The present invention is applied to a short-range wireless communication terminal that performs short-range wireless communication in the vicinity of a reader / writer that outputs a carrier wave of a predetermined frequency.
The configuration includes a coil antenna that performs wireless communication with a reader / writer in proximity, a communication circuit unit connected to the coil antenna, a holding member that holds the coil antenna in a planar shape, and first and second magnetic material sheets With.
The first magnetic sheet is disposed so as to cover a part of the area where the coil antenna is held on one surface of the holding member.
The second magnetic sheet is disposed so as to cover a part of the area where the coil antenna is held on the other surface of the holding member, and the covered range is the range covered with the first magnetic sheet. The range did not overlap.

  According to the present invention, a part of one surface of the holding member that holds the coil antenna in a flat shape is covered with the first magnetic material sheet, and a part of the other surface of the holding member is covered with the second magnetic material sheet. With this configuration, when this short-range wireless communication terminal is brought close to the reader / writer, even if any surface of the holding member is brought close to the reader / writer, it is close to the reader / writer. A magnetic material sheet is arranged on a part of the surface that is not.

According to the present invention, when any surface is brought close to the reader / writer, the magnetic material sheet is arranged on a part of the surface not close to the reader / writer. As a result, the magnetic flux loop from the reader / writer penetrates the coil antenna on the short-range wireless communication terminal side, and wireless communication can be performed satisfactorily.
Accordingly, the short-range wireless communication terminal of the present invention has no directionality in wireless communication sensitivity when performing wireless communication in the vicinity of the reader / writer, and the wireless communication terminal can be satisfactorily wireless regardless of which surface is close to the reader / writer. Since communication is possible, the user does not need to be aware of the surface to be brought close to the reader / writer, and the usability of this type of short-range wireless communication terminal is improved.

  An example of the first embodiment of the present invention will be described below with reference to FIGS.

  The example of this embodiment (hereinafter referred to as this example) is an example in which a short-range wireless communication terminal is configured as a non-contact type IC card provided with an RFID function unit. As described in the background art section, the non-contact type IC card performs wireless communication in the vicinity of a reader / writer. The distance at which the reader / writer and the IC card can communicate is, for example, a very close distance of several centimeters to several tens of centimeters. A carrier wave such as 13.56 MHz is used as a frequency for performing wireless communication between the reader / writer and the IC card. Note that the IC card applied in this embodiment is a so-called passive type that operates with a radio wave from a reader / writer. In this embodiment, such an IC card is referred to as a short-range wireless communication terminal. ing. A passive IC card (communication terminal) is usually configured not to incorporate a battery or the like, but to rectify a signal received from a reader / writer and store it in a capacitor to obtain a power source for operating the terminal. The power supply part such as a battery may be built in.

FIG. 1 is a view showing an example of an IC card as a short-range wireless communication terminal of this example, and FIG. 2 is an exploded view of each member of FIG.
As shown in FIG. 1, the IC card 10 of this example is configured as an IC card by disposing each part on a base material 11 made of a synthetic resin having a thin plate shape and a thickness of about 1 mm. That is, as shown in an exploded view in FIG. 2, a coil antenna 12 and an IC chip 13 connected to the coil antenna 12 are arranged on one surface of the base material 11. The IC chip 13 includes a circuit necessary for short-range wireless communication with a reader / writer, and the coil antenna 12 and the IC chip 13 constitute an RFID function unit. The coil antenna 12 is configured to be wound a predetermined number of times along the edge of the surface of the base material 11, and is configured by a thin film pattern, a wire, or the like.

  In the example of FIG. 2, these RFID function units are arranged on the base material 11, but may be configured to be embedded in the base material 11. Also, other members such as a thin film capacitor required by the RFID function unit may be arranged on the base material 11.

In this example, as shown in FIG. 2, a first magnetic material sheet 21 is attached to one end of the surface of the base material 11 on the side where the coil antenna 12 is arranged.
In addition, a second magnetic material sheet 22 is attached near the other end of the back surface, which is the surface of the base material 11 opposite to the side on which the coil antenna 12 is disposed.
The first and second magnetic material sheets 21 and 22 are made of a very thin resin sheet formed by filling a soft magnetic metal powder having a high magnetic permeability and a low magnetic loss, for example.

  When the IC card 10 is viewed in a plan view, the position where the first magnetic material sheet 21 is pasted (position disposed) and the position where the second magnetic material sheet 22 is pasted (position disposed) do not overlap. It is like that. Furthermore, when the IC card 10 is viewed in a plan view, a place where both the first magnetic material sheet 21 and the second magnetic material sheet 22 are not disposed is generated.

  Specifically, the base material 11 is covered with the first magnetic material sheet 21 from one end (the right side in FIG. 1) of the base material 11 to a range of, for example, about 1 to 2 cm, and the back side of the base material 11 The other magnetic material sheet 22 is covered from the other end (left side in FIG. 1) to a range of about 2 cm, for example. The place where both the magnetic material sheets 21 and 22 are arranged is a position overlapping the place where the coil antenna 12 is arranged at the end of the base material 11. And about the location where the center part of the coil antenna 12 is arrange | positioned, it is an area | region which does not overlap any magnetic material sheets 21 and 22. FIG. In addition, each magnetic material sheet 21 and 22 is arrange | positioned in the state insulated with the thin film or wire which comprises the coil antenna 12. FIG.

Further, as shown in FIG. 2, the surface of the IC card 10 is smoothed by stretching a protective film 31 after the first magnetic material sheet 21 is stretched. Also on the back surface side, after the second magnetic material sheet 22 is stretched, the protective film 32 is stretched so that the back surface of the IC card 10 becomes smooth.
It should be noted that some member (sheet) is arranged so that the thickness of the card does not change between the place where the magnetic material sheets 21 and 22 are arranged and the place where the magnetic material sheets 21 and 22 are not arranged. May be.

FIG. 3 is a cross-sectional view of the IC card 10 in a state where wireless communication is performed by bringing the IC card 10 of this example and the reader / writer 1 close to each other. In FIG. 3, the IC card 10 is close to the reader / writer 1 with the front surface shown in FIG. 1 as the lower side, and the back surface is the upper side. Further, it is assumed that the metal plate 6 is disposed in the vicinity of the IC card 10.
In the case of the IC card 10 of this example, at the place where the magnetic material sheet 21 is arranged on the surface facing the reader / writer 1 (on the left side in FIG. 3), the coil antenna at a position overlapping the magnetic material sheet 21. 12, the magnetic flux loop from the coil antenna 2 of the reader / writer 1 (the magnetic flux loop on the left side in FIG. 3) flows through the magnetic material sheet 21 to the coil antenna 12 because the magnetic material sheet 21 is present. Will not reach.

On the other hand, at the place where the magnetic material 22 is arranged on the surface opposite to the surface facing the reader / writer 1 (right side in FIG. 3), the magnetic material sheet 22 is placed on the back surface (upper side in FIG. 3) of the coil antenna 12. Therefore, when the magnetic flux loop passes through the magnetic material sheet 22, a magnetic flux loop is generated around the coil antenna 12, and the coil antenna 12 can receive a signal from the reader / writer 1.
Therefore, even if the metal plate 6 is close to the IC card 10 or the reader / writer 1, wireless communication can be satisfactorily performed.

Assuming that the back surface of the IC card 10 is brought close to the reader / writer 1, in this case, the positional relationship between the first magnetic material sheet 21 and the second magnetic material sheet 22 shown in FIG. Is just the opposite. Therefore, the magnetic flux loop from the reader / writer 1 passes around the coil antenna 12 at the place where the first magnetic material sheet 21 is disposed. On the contrary, at the place where the second magnetic material sheet 22 is disposed, the magnetic material sheet 22 prevents the passage of the magnetic flux loop.
Therefore, even when the direction of the IC card 10 is opposite, the signal from the reader / writer 1 can be received by the coil antenna 12 in the same state as shown in FIG.

In addition, a normal wireless communication state in which the metal plate is not close to the IC card is secured by the coil antenna 12 at a location where the magnetic sheets 21 and 22 are not disposed.
That is, as described above, the range a (see FIG. 1) in which the magnetic material sheet 21 is disposed is a reader / writer on the back surface (the lower surface in FIG. 1) of the IC card 10 in a state where the metal plate is in close proximity. When 1 is brought close, the magnetic flux is satisfactorily passed by the magnetic material sheet 21.
The range b (see FIG. 1) in which the magnetic material sheet 22 is arranged is when the reader / writer 1 is brought close to the surface of the IC card 10 (the upper surface in FIG. 1) in the state where the metal plate is close. This is a range in which the magnetic flux passes favorably due to the influence of the magnetic material sheet 22.
In addition, there is a central range c (see FIG. 1) in which neither the magnetic material sheet 21 nor the magnetic material sheet 22 is arranged, and therefore the metal antenna is not close to the coil antenna 12 in the range c. Wireless communication with the reader / writer 3 can be performed satisfactorily. That is, good near field communication is possible without causing deterioration of sensitivity even in a general use environment.

  As described above, according to the IC card 10 of this example, the magnetic material sheets 21 and 22 are arranged, so that when performing wireless communication in proximity to the reader / writer 1, even if the metal plate is in proximity. The wireless material can be satisfactorily performed by the action of the magnetic material sheet 21 or 22. Then, the surface on which the two magnetic material sheets 21 and 22 are arranged is set as another surface, and the arrangement positions of the two magnetic material sheets 21 and 22 are not overlapped, so that either the front surface or the back surface is brought close to the reader / writer 1. However, wireless communication can be performed satisfactorily. Therefore, the user who has the IC card 10 of this example does not need to consider the direction of the card when bringing it close to the reader / writer 1, and the usability of the IC card as an RFID is improved.

  Next, a second embodiment of the present invention will be described with reference to FIGS. 4 and 5, parts corresponding to those in FIGS. 1 to 3 described in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

  The present embodiment is also an example applied to an IC card that performs near field communication with a reader / writer.

FIG. 4 is a perspective view showing the configuration of the IC card 10 ′ in the present embodiment, and FIG. 5 is a cross-sectional view taken along the line VV in FIG. FIG. 4A is a diagram showing the front side, and FIG. 4B is a diagram showing the back side.
In this example, an RFID function unit such as a coil antenna 12 is disposed on the surface of the base material 11 as the IC card 10 '. And the 1st belt-shaped 1st magnetic material sheet | seat 41 of 1 round is arrange | positioned on the surface side so that the predetermined range inside the perimeter of the arrangement | positioning location of the coil antenna 12 may be covered. Furthermore, a belt-shaped second magnetic sheet 42 of one circumference is arranged on the back side of the base material 11 so as to cover a predetermined range outside the arrangement place of the coil antenna 12.

  As shown in a cross section in FIG. 5, the arrangement position of the first magnetic material sheet 41 and the arrangement position of the second magnetic material sheet 42 are positions that do not overlap vertically, and the remaining arrangement position of the coil antenna 12 In the range x of the portion (center portion), neither of the magnetic material sheets 41 and 42 is arranged above and below. This range x is provided over the entire circumference of the coil antenna 12. Also, with respect to the IC card 10 'of this example, protective films may be arranged on the front surface and the back surface, respectively, as in the example of FIG.

  4 and 5, even in the case of the communication state shown in FIG. 3, when the front side of the IC card 10 'is brought close to the reader / writer, and the back side is the reader / writer. In this case, the short range wireless communication can be satisfactorily performed. Furthermore, since there is the range x of the coil antenna 12 in which neither the first magnetic material sheet 41 nor the second magnetic material sheet 42 is arranged, the sensitivity deterioration is caused even in a general use environment where the metal plate is not close. Good short-range wireless communication that does not occur is possible. The range x of the coil antenna 12 that is not covered with the magnetic material sheet needs to be a range that can ensure the sensitivity of the antenna in a general use environment where the metal plate is not close.

In each of the above-described embodiments, an example of a short-range wireless communication terminal configured as a thin plate-like IC card has been described. However, any other communication terminal having a similar processing unit may be used as long as it is a communication terminal. Applicable to shapes. For example, the magnetic material sheets may be alternately arranged on one surface and the other surface of the location where the coil antenna of the RFID unit built in the mobile phone terminal device is disposed. Further, the present invention can also be applied to an RFID unit built in a device other than the mobile phone terminal device.
Even if it is configured as a stand-alone RFID, it can be applied to other configurations as long as part of the front side and part of the back side of the coil antenna are individually covered with a magnetic material sheet. Applicable.

It is a perspective view which shows the IC card by the example of the 1st Embodiment of this invention. It is a disassembled perspective view which decomposes | disassembles and shows the IC card by the example of the 1st Embodiment of this invention. It is explanatory drawing which shows the example of the radio | wireless communication state by the 1st Embodiment of this invention. It is the perspective view which shows the IC card by the example of the 2nd Embodiment of this invention, (a) shows the example of the surface side, (b) is the figure which showed the example of the back side. It is sectional drawing which follows the VV line of FIG. It is explanatory drawing which shows the example of the radio | wireless communication state of a reader / writer and an IC card. It is explanatory drawing which shows the example of a smart poster. It is explanatory drawing which showed the example of the communication state of a reader / writer and an IC card in the cross section, (a) is a normal communication state, (b) is a communication state when a metal plate is near, (c) is magnetic It is the figure which showed the communication state in case the material sheet is affixed. It is explanatory drawing which showed the state which a magnetic material sheet interferes and cannot perform wireless communication.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Reader / writer, 2 ... Coil antenna, 3 ... IC card, 4 ... Coil antenna, 6 ... Metal plate, 10, 10 '... IC card, 11 ... Base material, 12 ... Coil antenna, 13 ... IC chip, 21 , 22 ... Magnetic material sheet, 31, 32 ... Protective film, 41, 42 ... Magnetic material sheet

Claims (3)

In a short-range wireless communication terminal that performs short-range wireless communication in proximity to a reader / writer that outputs a carrier wave of a predetermined frequency,
A coil antenna for wireless communication with a nearby reader / writer;
A communication circuit unit connected to the coil antenna;
A holding member for holding the coil antenna in a planar shape;
A first magnetic sheet disposed so as to cover a part of a region where the coil antenna is held on one surface of the holding member;
The other surface of the holding member is disposed so as to cover a part of the region where the coil antenna is held, and the covered range is a range that does not overlap with the range covered with the first magnetic sheet. A short-range wireless communication terminal comprising: a second magnetic sheet. The short-range wireless communication terminal according to claim 1,
The first magnetic sheet is disposed so as to cover the coil antenna in the first angle range in which the coil antenna held by the holding member is wound 360 °,
The short-range wireless communication terminal, wherein the second magnetic sheet is disposed so as to cover a coil antenna in a second angle range that does not overlap the first angle range. The short-range wireless communication terminal according to claim 1,
The first magnetic sheet is arranged so as to cover the coil antenna in the first range of the entire circumference of the coil antenna held in a planar shape by the holding member,
The short-range wireless communication terminal, wherein the second magnetic sheet is disposed so as to cover a coil antenna in a second range of the entire circumference that does not overlap the first range.

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