JPH11122146A - Ic card system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize efficient power transmission and information communication or the like with high quality in a reader/writer and an IC card where power is transmitted by a power transmission antenna and information is communicated by using an information communication antenna. SOLUTION: For example, in a reader/writer 2, a power transmission antenna 13 and an information communication antenna 14 are placed on the same plane and both the antennas are placed while axial lines s, t of coils of both the antennas 13, 14 are set orthogonally to each other so as to prevent interference resulting from electromagnetic coupling between both the antennas. Furthermore, a coil of the information communication antenna 14 is divided into plural segments 14a, 14b and they are arranged so that a voltage induced in the segment 14a interlinked with a magnetic flux of external noise is cancelled with a voltage induced in the other segment 14b to reduce the effect on the information communication antenna 14 due to the magnetic flux of external noise.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an IC for transmitting power and communicating information in a non-contact manner from a reader / writer to a mobile object such as an IC card using a power transmission antenna and an information communication antenna. Regarding the card system,
In particular, for example, in a reader / writer, by suppressing the electromagnetic coupling generated between the power transmission antenna and the information communication antenna, and by reducing the influence of the magnetic flux of external noise on the information communication antenna, the reader / writer can be used. The present invention relates to a technology for improving the efficiency of power transmission and the quality of information communication between a writer and an IC card or the like. In addition, in the mobile system using a mobile body such as a tag that permits thickness or size, for example, the present invention is also considered to be applied to a mobile body that performs power transmission or information communication with a reader / writer. I have.

[0002]

2. Description of the Related Art For example, an IC card formed by embedding a microcomputer chip and a memory chip on a card substrate having a size similar to that of a credit card or the like has been put to practical use in various fields such as finance, distribution, transportation, and medicine. Is planned. In an IC card system using such an IC card, power is transmitted and supplied from a reader / writer to the IC card, and information such as a control code and data is communicated between the reader / writer and the IC card.

In power transmission and information communication between a reader / writer and an IC card, a non-contact method using electromagnetic coupling is employed in addition to a contact method in which terminals are brought into contact with each other. Various modes are also studied in the non-contact system, but a two-frequency system in which the frequency for power transmission and the frequency for information communication are different has been studied. For example, in a single-frequency system in which the frequency for power transmission and the frequency for information communication are the same, two-way communication cannot be simultaneously performed between the reader / writer and the IC card. Since two-way communication can be simultaneously performed with the IC card, the efficiency of information communication can be further improved as compared with the one-frequency system.

In such a two-frequency system, it is preferable to separately provide a power transmission antenna for transmitting power and an information communication antenna for communicating information. For example, both antennas have different frequencies. By transmitting a current, power transmission and information communication are performed. Specifically, for example, an I / O with a reader / writer and an IC card
In the C card system, power transmission between the reader / writer and the IC card is performed by electromagnetic coupling between power transmission antennas, and information communication between the reader / writer and the IC card is performed by electromagnetic coupling between information communication antennas. Done.

[0005] The arrangement of these two antennas is as follows.
For example, as shown in FIG. 17, the direction of the axis of the coil constituting the power transmission antenna 41 and the information communication antenna 42
So that the direction of the axis of the coil constituting
It is generally considered that these two antennas 41 and 42 are arranged in an overlapping manner. In the figure, the coils constituting these antennas 41 and 42 are arranged such that the axial direction of the coils is the Z-axis direction.

[0006]

However, in the above-described antenna arrangement, mutual interference occurs between the power transmission antenna and the information communication antenna due to electromagnetic coupling. There is a problem that sufficient power cannot be transmitted to the IC card, and a problem that the quality of information communication performed between the reader / writer and the IC card is deteriorated.

FIG. 18 is a side view (a view on the XZ plane) of the two antennas 41 and 42 shown in FIG. 17, and as shown in FIG. The magnetic flux φ5 generated by flowing the high-frequency current i4 through the antenna 41 interferes with its own information communication antenna 42, and the magnetic flux emitted from the power transmission antenna 41 is coupled to the information communication antenna 42, and power is transmitted from the power transmission antenna 41. In addition to the power consumed by the information communication antenna 42, the information communication antenna 42 causes a guidance failure in the communication. In FIG. 18, for convenience of explanation, the power transmission antenna 41 and the information communication antenna 42 are shown shifted from each other in the Z-axis direction. However, in general, these two antennas 41 and 42 are arranged in the same plane. .

[0008] Similarly, in a mobile system such as a tag which permits a certain thickness or size, for example, a mobile system for performing power transmission and information communication between a mobile device and a reader / writer, for example, in the mobile device, a reader is provided. The magnetic field emitted from the information communication antenna to transmit information to the writer interferes with its own power transmission antenna, which lowers the efficiency of the antenna used for information communication and lowers the communication quality. . As described above, in the antenna arrangement as described above, there is a problem that the efficiency of power transmission and the quality of information communication are deteriorated. Therefore, interference generated between the power transmission antenna and the information communication antenna is caused. There was a demand to reduce emissions.

Further, in the configuration of the information communication antenna as described above, a voltage is induced by the magnetic flux of the external noise penetrating the coil constituting the antenna, whereby the voltage is induced.
There has been a problem that the quality of information communication is reduced. For this reason, there has been a demand to reduce the influence of the magnetic flux of external noise on the information communication antenna.

SUMMARY OF THE INVENTION The present invention has been made to solve such a conventional problem, and it is an object of the present invention to reduce the interference between the power transmission antenna and the information communication antenna by suppressing interference between the two antennas. It is another object of the present invention to provide a reader / writer arranged to realize high-quality information communication. Further, the present invention provides a mobile object in which a power transmission antenna and an information communication antenna are arranged so as to realize efficient power transmission and high quality information communication by suppressing interference between the two antennas. The purpose is to do.

Further, the present invention provides an information communication antenna,
It is an object of the present invention to provide a reader / writer arranged so as to reduce the influence of external magnetic flux. In addition, the present invention arranges the information communication antenna so as to reduce the influence of the magnetic flux of the external noise, improves the convenience of the user, and improves the quality of the information communication with the mobile object. It is an object of the present invention to provide a reader / writer capable of causing the reader / writer to operate. Also, the present invention provides a reader / writer in which an information communication antenna is arranged to reduce the influence of external noise magnetic flux based on the fact that the voltage induced in the coil by the magnetic flux depends on the winding direction of the coil. The purpose is to provide.

Further, the present invention provides an information communication antenna,
It is an object of the present invention to provide a moving body arranged so as to reduce the influence of external magnetic flux. According to the present invention, in a reader / writer, the information communication antenna is arranged so as to reduce the influence of external magnetic flux, and the power transmission antenna and the information communication antenna are interposed between the two antennas. It is an object of the present invention to provide an IC card system arranged so as to realize efficient power transmission and high-quality information communication by suppressing noise.

[0013]

In order to achieve the above object, a reader / writer according to the present invention uses a power transmission antenna, such as an IC card, for transmitting power to a mobile body, and communicates information between the mobile body and the power transmission antenna. And an information communication antenna for performing the above-mentioned operations are arranged in the same plane, and the axes of the coils constituting these antennas are orthogonal to each other. Therefore, it is possible to prevent interference between the two antennas, for example, a magnetic flux generated by flowing a high-frequency current through the power transmission antenna such that the magnetic flux interferes with its own information communication antenna. Transmission and high-quality information communication can be realized.

That is, in general, when a high-frequency current is applied to a coil, a magnetic flux in the same direction as the axis of the coil is generated in the loop of the coil, and the magnetic flux is applied to the coil in the loop of the coil. Since the voltage is induced in response to the temporal change of the magnetic flux in the same direction as the coil axis, the power transmission antenna and the information communication antenna have their coil axes orthogonal to each other as described above. In the arrangement, it is possible to prevent interference between these two antennas due to electromagnetic coupling.

In addition, for example, power is generated by a power transmission antenna or an information communication antenna due to a power supply provided in a reader / writer, an external device, a printed circuit board provided with an antenna, and the like. The magnetic flux may be distorted.In such a case, the axes of the coils constituting both antennas do not necessarily have to be completely orthogonal to each other. It is preferable to slightly adjust the tilt of the two antennas so as to completely offset or reduce the interference between the two antennas with a slight shift from the orthogonal state.

As described above, the present invention includes not only a state in which both antennas are completely orthogonal to each other, but also a state in which the inclination of both antennas is finely adjusted by shifting the inclination from such an orthogonal state. An arrangement that can further reduce the interference between the antenna and the information communication antenna is preferable. In the present invention, the case where the axes of the coils constituting both antennas are located at the twisted position is also included, and the axes of the coils constituting the power transmission antenna and the axes of the coils constituting the information communication antenna do not always intersect. It is not necessary that the directions of the axes of the coils forming both antennas be perpendicular to each other.

Further, according to the present invention, the direction of the magnetic flux generated by the coil forming one antenna on the coil surface and the direction of the magnetic flux generated by the coil forming the other antenna on the coil surface are substantially determined. This includes placing both antennas so as to be orthogonal to each other. In other words, by making the magnetic flux directions on the coil surfaces of the two antennas substantially orthogonal in this way, mutual interference due to electromagnetic coupling between the two antennas can be prevented to an extent corresponding to the arrangement, which is necessary for practical use. A wide range of effects can be realized.

Further, similarly, the arrangement of both antennas in the same plane is more difficult than the state in which both antennas are completely arranged in the same plane due to the influence of external equipment and the like. In some cases, it may be possible to reduce interference between the two antennas by finely adjusting the position from the state.In this invention, not only the state where both antennas are completely in the same plane, A state in which the arrangement of both antennas is shifted from this state and finely adjusted is also included.

Regarding the arrangement relationship between the power transmission antenna and the information communication antenna, even if the above-mentioned orthogonal state or the state of being arranged in the same plane is not completely realized, these two antennas are almost orthogonal. If the state in which the antennas are arranged and the state in which the two antennas are arranged in substantially the same plane are realized, the mutual interference between the two antennas can be reduced to an extent corresponding to the arrangement. To orthogonalize the two antennas or to arrange both antennas in the same plane, the arrangement relationship between the two antennas is slightly shifted from a completely orthogonal state or a state of being completely arranged in the same plane. The arrangement | positioning aspect is also included.

That is, the term "to make the axes of the two antenna coils orthogonal to each other and to arrange the two antenna coils in the same plane" as used in the present invention is a concept of allowing a width such as inclination as described above. The positional relationship is such that the total amount of magnetic flux generated from one antenna coil penetrating the other antenna coil surface perpendicularly is completely canceled or reduced, and interference between both antenna coils is prevented to the extent that there is no practical problem. I just need.

In the mobile unit according to the present invention, the antenna arrangement in the reader / writer described above is applied to a mobile unit such as a tag which allows a certain thickness, for example, to transmit power from the reader / writer. The antenna for communication and the antenna for information communication for communicating information between the reader / writer were arranged on the same plane, and the axes of the coils constituting both antennas were orthogonal to each other. Therefore, similarly to the case of the reader / writer described above, for example, the interference between the two antennas such that the magnetic flux emitted from the information communication antenna for transmitting information to the reader / writer interferes with its own power transmission antenna. Thus, efficient power transmission and high-quality information communication can be realized. In addition, such an antenna arrangement is applicable to a moving object that allows a thickness and a size for storing the power transmission antenna and the information communication antenna arranged as described above.

Further, in the reader / writer according to the present invention, a coil constituting an information communication antenna for communicating information with a mobile body is divided into a plurality of segments, and a part of the segments is divided by a magnetic flux of external noise. The arrangement was such that the induced voltage and the voltages induced in other segments were offset. In such an arrangement, when a magnetic flux of external noise which has a substantially uniform influence on each segment from the same direction is input, the voltage induced in the partial segments by the magnetic flux of the external noise and the other The sum of the voltages induced in the plurality of segments, that is, the sum of the electromotive voltages received by the entire information communication antenna due to the magnetic flux of the external noise is calculated so that the voltage induced in the segment is canceled.

Therefore, even when the magnetic flux of the external noise penetrates the information communication antenna, the sum of the voltage induced in some of the segments and the voltage induced in the other segment is canceled out. That is, since the voltages induced in the plurality of segments act so as to cancel each other, the influence of the magnetic flux of the external noise on the information communication antenna as a whole can be reduced. Can be realized.

It is to be noted that the sum of the electromotive voltages in the partial segments and the other segments is offset when the electromotive voltages in the respective segments contribute to the total voltage induced in the information communication antenna. It is offset in such a point. That is, in the present invention, the sum of the electromotive voltages generated in all the segments becomes the total electromotive voltage generated as the entire information communication antenna. For example, when the information communication antenna is not divided and only one coil is provided as the antenna. In comparison, by using an arrangement in which the total sum of the electromotive voltages generated in the partial segments and the other segments is offset and reduced by the magnetic flux of the external noise,
It is realized that the influence of the magnetic flux of external noise is reduced as a whole.

Here, in the present invention, the voltage induced in some of the segments and the voltage induced in the other segment are completely canceled out (that is, the sum of these electromotive voltages is zero by the cancellation). Is preferably used, but is not necessarily limited to such an arrangement, and the voltage induced in some of the segments and the voltage induced in the other segments are partially canceled out ( That is, the sum of these electromotive voltages is reduced, if not eliminated, by cancellation.) An arrangement may be used.

As an arrangement for realizing such an offset of the electromotive voltage, for example, the voltage induced in some of the segments and the voltage induced in the other segments due to the magnetic flux of external noise are defined as these. It can be configured by connecting the segments so that they are canceled each other when the sum of the electromotive voltages is obtained. In other words, by connecting the segments based on the direction and magnitude of the electromotive voltage generated in each segment by the magnetic flux of the external noise so that the sum of the electromotive voltages in the plurality of segments is offset, the external noise is reduced. An arrangement that can reduce the influence of the magnetic flux on the entire information communication antenna can be realized.

For example, when the information communication antenna is divided equally into two segments, it is preferable to arrange the two segments so that the angle between the two segments is 180 degrees. By connecting the two segments so as to cancel each other, the sum of the electromotive voltages applied to the entire information communication antenna by the magnetic flux of the external noise can be reduced to zero.
Further, for example, when the information communication antenna is divided into three segments, it is preferable to arrange the three segments symmetrically so that the angle formed by each of the three segments is 120 degrees. By connecting the segments so that the induced voltage is canceled out, it is possible to cancel out the sum of the electromotive voltages received by the entire information communication antenna due to the magnetic flux of the external noise.

As for the mode of arranging the plurality of divided segments, any arrangement that can completely cancel or reduce the influence of the magnetic flux of the external noise on the entire information communication antenna can be used. Such an arrangement may be used. For example, an arbitrary embodiment such as an embodiment in which all segments are arranged in the same plane, an embodiment in which these segments are arranged in a three-dimensional manner, and the like are used. May be.

Further, in the reader / writer according to the present invention, a communication recommendation area is provided between the segments so as to hold the mobile object and perform information communication with the mobile object. Therefore, since a communication recommended area suitable for holding a mobile object such as an IC card is shown on the outer surface of the reader / writer, the user holds the mobile object over the communication recommended area.
High-quality information communication can be performed between the reader / writer and the IC card, and the convenience for the user can be improved.

That is, when the moving object is held between the segments, the directions of the electromotive voltages of the partial segments and the other segments match, and these electromotive voltages are applied to reinforce each other. Therefore, the quality of information communication can be improved. Here, in the present invention, not only the case where the moving body is positioned above the reader / writer, but also, for example, the case where the moving body is positioned below the reader / writer and held over the communication recommended area provided below the reader / writer Are also included.

Further, in the reader / writer according to the present invention, by arranging the partial segments and the other segments so that the winding directions of the coils are opposite to each other, both of the segments are affected by the magnetic flux of external noise. The sum of the induced voltages was offset. Therefore, even in such a configuration, similarly to the above, for example, compared with the case where the information communication antenna is not divided and only one coil is provided as the antenna, the partial segments and the The sum of the electromotive voltages generated with other segments can be offset and reduced.

Specifically, for example, when the coil constituting the information communication antenna is equally divided into two segments, the angle formed by these two segments is set to 180 degrees.
By changing the winding directions of the coils constituting both segments so that they are wound clockwise and counterclockwise, the total sum of the voltages induced in these segments can be completely canceled. Thus, by changing the winding direction of the coil of the segment between the right-handed winding and the left-handed winding, the direction in which each segment contributes to the sum of the electromotive voltages is changed to one of the opposite directions. be able to.

Further, in the moving body according to the present invention, the arrangement of the information communication antenna in the reader / writer is applied to provide a plurality of coils constituting the information communication antenna for communicating information with the reader / writer. , And arranged so that the voltage induced in some segments and the voltage induced in other segments are offset by the magnetic flux of external noise. Therefore, similarly to the case of the above-described reader / writer, the influence of the magnetic flux of the external noise on the information communication antenna can be reduced, thereby realizing high-quality information communication. In addition,
Such an antenna arrangement can be applied to a mobile body that allows a size or the like for storing the information communication antenna configured as described above.

Here, the moving body referred to in the present invention includes not only the above-mentioned IC card, the tag attached to the product or the article, but also a name plate, an identification plate attached to livestock, and a home delivery service. A delivery destination plate attached to a package, a delivery destination plate attached to a container, and the like are also included. That is, for example, a system that reads information by communicating information with a tag attached to a product by a reader / writer, or communicates information with a tag attached to an article flowing on a belt conveyor by a reader / writer. By applying the present invention to a system for performing sorting and the like, efficient power transmission and high-quality information communication between a reader / writer and a tag can be realized.

The moving object to which the present invention can be applied is not limited to those described above.
The present invention can be widely applied to various kinds of devices that perform authentication processing, identification processing, and the like by performing information communication and the like with a reader / writer.

Further, in the IC card system according to the present invention, the reader / writer is provided with a power transmission antenna for transmitting power and an information communication antenna for communicating information separately, and the information communication antenna is provided in the same plane. The coil constituting the communication antenna is divided into a plurality of segments, and arranged so that the voltage induced in some segments and the voltage induced in other segments are offset by the magnetic flux of external noise, In addition, the power transmission antenna and the information communication antenna are arranged in the same plane, and the axes of the coils constituting both antennas are orthogonal to each other. With this arrangement, power is transmitted from the reader / writer to the IC card using the power transmission antenna, and information is communicated between the reader / writer and the IC card using the information communication antenna.

Accordingly, as described above, interference between the two antennas can be prevented to realize efficient power transmission and high-quality information communication, and the information communication antenna can be used by the magnetic flux of external noise. It is possible to reduce the influence. As described above, it is preferable to use the antenna arrangement for preventing interference between the two antennas and the antenna arrangement for reducing the influence of the magnetic flux of external noise on the information communication antenna, and in this case, As compared with the case where only one of the antenna arrangements is used, the quality of information communication and the like can be ensured more reliably.

[0038]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment according to the present invention will be described with reference to the drawings. In this example, a case where an IC card is used as a moving object will be described as an example. As shown in FIG. 1, the IC card system according to the present embodiment is configured such that a reader / writer 2 connected to an information terminal device 1 that performs data processing such as finance, distribution, traffic, medical treatment, etc. An IC card 3 for communicating information and transmitting power by a contact method.

In this system, for example, the reader / writer 2
The reader / writer 2 and the IC card 3 are held by holding the IC card 3 over a portion where the antenna is disposed.
And power communication and information communication using an antenna. That is, the IC card 3 operates using the power supplied wirelessly from the reader / writer 2 as energy,
Information such as control commands and write data to the C card 3 is wirelessly communicated from the reader / writer 2 to the IC card 3 and information such as read data from the IC card is wirelessly communicated from the IC card 3 to the reader / writer 2. Is done.

As shown in FIG. 2, a reader / writer 2 includes an interface 11 for communicating information with the information terminal device 1 and a power supply circuit 1 for receiving power from an external power supply (not shown).
2, a power transmission antenna 13 for transmitting power to the IC card 3, an information communication antenna 14 for communicating information with the IC card 3, and a control for causing these units 11 to 14 to function and control. A transmission / reception unit 15.

The control transmission / reception unit 15 includes, for example, a microcomputer having a memory storing a control program and a CPU for executing the program, and a transmission / reception circuit. To be transmitted from the power transmission antenna 13, and from the information terminal device 1 to the interface 11.
Is converted into a form suitable for wireless communication and transmitted from the information communication antenna 14, and the information received by the information communication antenna 14 is demodulated and transmitted to the information terminal device 1 via the interface 11. It has functions such as sending to

FIG. 3 shows an example of an antenna arrangement of the power transmission antenna 13 and the information communication antenna 14.
In this arrangement, a power transmission antenna 13 composed of a coil wound in a rectangular loop and an information communication antenna 14 composed of a coil divided into two segments 14a and 14b are provided. Here, two segments 14a constituting the information communication antenna 14,
14b is divided so as to be a coil having the same number of turns and the same winding direction.

In the present embodiment, it is assumed that the winding directions of these two segments 14a and 14b are both right-handed, and that these segments 14a and 14b are each constituted by a coil wound around a magnetic core. I do. As described above, in the present embodiment, the antenna wound on the magnetic core is used as the information communication antenna 14 to increase the antenna sensitivity to the magnetic flux. However, for example, even when an air-core coil is used, Except for the points such as the antenna sensitivity to magnetic flux and the like, it is the same as the case using the magnetic core.

As shown in FIG. 3, the power transmission antenna 13 and the information communication antenna 14 are disposed on the same plane. In this example, the coil segments 14a and The axis t common to the segments 14b is arranged so as to be located on the same plane as the coil constituting the power transmission antenna 13. That is, in this example, the segments 14a and 14b of the information communication antenna 14
Are arranged so as to be divided into two equal parts by the surface of the coil that constitutes. Note that the arrangement as shown in FIG. 3 is not necessarily used, and the point is that an arrangement in which the power transmission antenna 13 and the information communication antenna 14 are located in the same plane may be used.

In FIG. 3, the axis s of the coil forming the power transmission antenna 13 is in the Z-axis direction, and the common axis t of the coil 14a and the segment 14b of the coil forming the information communication antenna 14 is shown. Is Y
It is arranged to be in the axial direction. That is, the axes s and t of the coils constituting the antennas 13 and 14 are orthogonal to each other. In this example, the position of the center of gravity of the information communication antenna 14, that is, the segment 14
The position of the midpoint between a and the segment 14b is located on the axis s of the power transmission antenna 13.

In this antenna arrangement, for example, as shown in FIG. 4 which is a side view of the arrangement in the YZ coordinates, a magnetic flux φ1 generated by flowing a high-frequency current i1 to the power transmission antenna 13 has an information communication antenna. Due to the reciprocity theorem, the magnetic flux generated when a high-frequency current flows through the information communication antennas 14a and 14b does not affect the power transmission antenna 13 either. That is, in this arrangement,
The effect of the magnetic flux φ1 generated from the power transmission antenna 13 on the segments 14a and 14b is offset as a whole, and the magnetic flux generated from the information communication antenna 14 has no effect on the power transmission antenna 13. In addition,
FIG. 5 is a side view of the above-described antenna arrangement in XZ coordinates.

Therefore, it is possible to suppress the occurrence of electromagnetic coupling between the power transmission antenna and the information communication antenna, and to prevent the occurrence of interference between these two antennas. It is possible to realize efficient power transmission and high quality information communication between the IC card and the IC card. That is, in the antenna arrangement as described above, the magnetic flux generated from one antenna coil penetrates the surface of the other antenna coil vertically, and at the same time, the total amount is cancelled, so that interference between both antenna coils can be prevented. Further, even when the power transmission antenna and the information communication antenna are arranged close to each other as in this example, it is possible to prevent electromagnetic coupling from occurring between these two antennas. The area occupied by the antenna can be reduced, and the practical effect can be enhanced.

When the magnetic flux generated by the power transmission antenna or the information communication antenna is affected by the power supply circuit or the like provided in the reader / writer, for example, the inclinations of the coils constituting both antennas may be changed. Fine adjustments can be made with a slight shift from the position where both antennas are completely orthogonal, and fine adjustments can be made on the positions of both antennas with a slight shift from the state where both antennas are completely in the same plane. May be. As described above, when the antenna is affected by various situations, it is preferable that the arrangement of the antennas is finely adjusted to further reduce the interference between the two antennas. That is, the total amount of magnetic flux generated from one antenna coil passing perpendicularly through the other antenna coil surface is completely canceled or reduced,
The two antennas may be arranged in such a positional relationship that interference between the two antenna coils is prevented to such an extent that there is no practical problem.

Further, as described above, even if the arrangement relationship between the two antennas is not completely orthogonal or completely arranged in the same plane, the two antennas are almost orthogonal, Is realized in a state where the antennas are arranged in substantially the same plane, mutual interference between the two antennas can be reduced to an extent corresponding to the arrangement. A mode may be used in which the antennas are arranged in a state of being completely orthogonal to each other or slightly deviating from a state of being completely in the same plane.

In the antenna arrangement shown in FIG. 3, the voltage of one coil 14a and the voltage of another coil 14b caused by the magnetic flux of the external noise are changed for the coil constituting the information communication antenna 14. Are arranged in opposite directions. In other words, both segments 14a,
The arrangement is such that the voltages induced by the information communication antennas 14 are generally opposite to each other and the voltages induced by the information communication antenna 14 are generally reduced.

Here, generally, the magnetic flux of external noise can be regarded as a uniform magnetic flux in the same direction. In this example, as shown in FIG. 6, the antenna arrangement in the XY coordinates, for example, when the magnetic flux φ2 of the external noise penetrates both segments 14a and 14b along the Y-axis direction,
In a and 14b, voltages of the same magnitude are induced. For this reason, as shown in the figure, by connecting and connecting the two segments 14a and 14b so that the voltages induced in the two segments 14a and 14b by the magnetic flux φ2 of the external noise cancel each other, this flux φ2 As a result, the voltage induced by the information communication antenna 14 can be offset. Further, in the arrangement of this example, when the magnetic flux of the external noise is in the X-axis direction or the Z-axis direction, the magnetic flux is orthogonal to the axis of the coil of both segments 14a and 14b. Does not induce a voltage.

Therefore, the voltage induced between the terminal A and the terminal B of the information communication antenna 14 can be canceled by the magnetic flux φ2 of the external noise, thereby realizing high quality information communication. it can. Here, in the present example, as the most preferable aspect of the present invention, a case is shown in which the sum of voltages induced in a plurality of segments constituting the information communication antenna is completely canceled by the magnetic flux of external noise. The present invention is not limited to the antenna arrangement which causes such complete cancellation of the electromotive voltage.For example, the voltage induced in some segments by the magnetic flux of external noise and the voltage induced in other segments are partially reduced. An offset configuration may be used. That is, by using an arrangement in which the voltage induced in some segments by the magnetic flux of the external noise and the voltage induced in the other segments cancel each other, the information communication antenna is generally received by the magnetic flux of the external noise The effect of completely or partially canceling out the influence can be obtained in a degree corresponding to the setting, and an effect in a practically necessary range can be realized.

In this embodiment, the information communication antenna 14
Is divided into a plurality of segments having the same winding direction. For example, as shown in FIG. 7, the coil forming the information communication antenna 14 is divided into a segment 14c and a segment 14d whose winding directions are opposite to each other. Even when divided, these segments 14c and 14d can be connected so as to obtain the same effect. For example,
When the magnetic flux φ2 of the external noise penetrates the information communication antenna 14 along the Y-axis direction, the segment 14c which is a left-handed coil and the segment 14c which is a right-handed coil
In d, voltages of the same magnitude and opposite to each other with respect to the Y-axis direction are induced.

For this reason, as shown in FIG. 14, both segments 14c and 14d are induced by the magnetic flux φ2 of the external noise so that the voltages induced in both segments 14c and 14d cancel each other.
By connecting and connecting between c and 14d, the voltage induced by the information communication antenna 14 as a whole can be canceled by the magnetic flux φ2.

The coil constituting the information communication antenna need not necessarily be divided into a plurality of segments having the same number of turns, and the number of turns of the coil in each segment may be arbitrary. Further, the number of turns of the coil as the whole information communication antenna may be arbitrary. Also,
Similarly, the number of turns of the coil constituting the power transmission antenna may be arbitrary.

In this example, the coil constituting the information communication antenna is divided into two segments. However, the number of segments to be divided may be any number as long as it is plural. Here, FIG. 8 shows an example of an antenna arrangement when the information communication antenna is divided into three segments. In the antenna arrangement shown in the figure, the information communication antenna 14 is divided into three right-handed segments 14e, 14f, and 14g in the same plane, and the number of turns of the coils of the segments 14f and 14g is equal. . These two segments 14f, 1f
The axes of the coils constituting 4g make the same angle with the X axis, and the segments 14f and 14g are arranged so that the axes intersect each other. The segments 14e are arranged so that the axis of the coil is in the Y-axis direction.

It is more preferable that the three segments 14e, 14f, and 14g have the same number of coils and that the segments 14e, 14f, and 1g have the same number of turns.
The antenna arrangement should be such that an equilateral triangle is formed when the positions where 4g are arranged are connected. In this case, for example, these three segments 14e, 14f, 1
The axes of the coils constituting 4g intersect at one point, and the angles formed by the axes of these three segments 14e, 14f, 14g are equal to each other.

In the above arrangement, the two segments 14f and 14g respond to external magnetic flux in the Y-axis direction.
Is equal to the magnitude of the voltage induced in the segment 14e by the magnetic flux, for example, and the three segments 14e, 14f, and 14g are connected so that they cancel each other. It is connected. Also, these segments 14e, 14f, 1
The voltage induced by 4 g is configured to cancel each other. As described above, even when the coil constituting the information communication antenna is divided into three segments, the influence of the magnetic flux of the external noise can be reduced.
Even when divided into one or more segments, the influence of the magnetic flux is reduced by arranging such that the sum of the voltages induced in some segments and other segments is offset by the magnetic flux of the external noise. be able to.

Further, as shown in FIG.
Is a power transmission antenna 21 for receiving the power transmitted from the reader / writer 2, an information communication antenna 22 for communicating information with the reader / writer 2, and data for finance, distribution, transportation, medical care, etc. Memory 2 for storing read / write freely
3 and a control transmission / reception unit 24 for causing these units 21 to 23 to function and control.

The control transmission / reception unit 24 includes, for example, a microcomputer and a transmission / reception circuit having a memory storing a control program and a CPU for executing the program, and controls the transmission of the magnetic flux received by the power transmission antenna 21. The change is converted into electric power, the information read from the memory 23 is converted into a form suitable for wireless communication and transmitted from the information communication antenna 22, and the information received by the information communication antenna 22 is demodulated. It has functions such as writing in the memory 23.

In this embodiment, the power transmission antenna 21 and the information communication antenna 22 of the IC card 3 are each formed of a coil wound in a rectangular shape or the like.
Note that, as a moving body such as an IC card 3 that performs power transmission and information communication with the reader / writer 2, for example, a moving body such as a nameplate or a tag that allows a certain thickness or size is included in the above described moving body. The same antenna arrangement as the reader / writer 2 described above can be applied. That is, the arrangement of the power transmission antenna and the information communication antenna provided in such a mobile body is the same as the power transmission antenna 13 and the information communication antenna 14 of the reader / writer 2 described with reference to FIGS. Thus, efficient power transmission and high-quality information communication can be realized. Further, the antenna arrangement according to the present invention,
It can be applied to both reader / writer and mobile object,
Thereby, the above-mentioned effect can be realized more reliably.

Next, power transmission and information communication between the reader / writer 2 and the IC card 3 will be described with reference to the drawings. In this example, a case where the present invention is applied to only the reader / writer 2 will be described as an example. That is, in the reader / writer 2, the power transmission antenna 13 and the information communication antenna 14 are provided in the antenna arrangement shown in FIG. 3, and the IC card 3 is formed in a square loop shape as described above. It is assumed that a wound power transmission antenna 21 and an information communication antenna 22 are provided.

As shown in FIG. 10, for example, as shown in FIG. 10, the power transmission from the reader / writer 2 to the IC card 3 and the information communication are performed by using the axis of the coil constituting the power transmission antenna 13 of the reader / writer 2 and the power of the IC card 3. The IC so that the axis of the coil constituting the transmission antenna 21 is in the same direction as that of the coil.
The operation is performed by holding the card 3 over the reader / writer 2. That is, by passing a high-frequency current i2 between the terminal C and the terminal D of the power transmission antenna 13 of the reader / writer 2,
For example, a magnetic flux φ3 penetrating the coil from the top to the bottom is generated in the coil constituting the antenna 13, and the magnetic coupling generated in the power transmission antenna 21 of the IC card 3 due to the magnetic flux φ3 causes Power is received by the power transmission antenna 21.

In this case, generally, the coil surface forming the power transmission antenna 13 of the reader / writer 2 and the IC card 3
As the area of the overlapping portion with the coil constituting the power transmission antenna 21 is larger, the power transmission can be performed more efficiently. The power generated by the power transmission antenna 13 of the reader / writer 2 causes
Information to be transmitted to the card 3 can be superimposed. That is, in this example, the power transmission antenna 13 of the reader / writer 2 is also used as an antenna for downlink communication of information to the IC card 2.

In the upward communication of information from the IC card 3 to the reader / writer 2, for example, as shown in FIG. 11, information communication between the axis of a coil constituting the power transmission antenna 13 of the reader / writer 2 and the IC card 3 is performed. The IC card 3 is held over the reader / writer 2 so that the axis of the coil forming the antenna 22 is in the same direction. On this occasion,
As shown in FIG. 11, the magnetic flux φ4 generated by the high-frequency current i3 flowing through the information communication antenna 22 of the IC card 3 causes the information communication antenna 1 of the reader / writer 2
The IC card 3 is positioned with respect to the reader / writer 2 such that the IC card 3 passes through the antenna 4 in the same direction as the axis of the coil constituting the antenna 14.

FIG. 12 shows the antennas 13 and 14 of the reader / writer 2 and the antenna 2 of the IC card 3 shown in FIG.
FIG. As shown in the figure, the magnetic flux φ4 generated from the information communication antenna 22 of the IC card 3 is applied to the two segments 14a and 14b constituting the information communication antenna 14 of the reader / writer 2 in the Y-axis direction. Penetrate in opposite directions.

In this case, the voltages induced by the coils 14a and 14b are in the same direction and reinforce each other, so that the information communication antenna 14 of the reader / writer 2 is totally driven by the magnetic flux φ4 generated from the IC card 3. The magnitude of the received electromotive voltage is increased. That is, reader / writer 2
The magnitude of the voltage V induced between the terminal A and the terminal B of the information communication antenna 14 is increased. In this case, it is generally better to position the information communication antenna 22 of the IC card 3 above the segments 14a and 14b constituting the information communication antenna 14 of the reader / writer 2, for example. , 14b, it is possible to perform higher-quality information communication as compared with the case where the position is deviated from the position between.

As described above, in the configuration of the information communication antenna of the reader / writer according to the present embodiment, the quality of the information communication performed between the reader / writer and the IC card can be improved. In addition, the influence of external magnetic flux due to magnetic flux can be reduced. The power transmission antenna 21 and the information communication antenna 22 of the IC card 3 may be shared by one antenna.

As described above, in general, when the IC card is held between the segments constituting the information communication antenna of the reader / writer, higher quality information is obtained than when the IC card is held off the segments. Communication can be performed. For this reason, it is preferable to provide a communication recommended area where the IC card is to be held over the outer surface of the reader / writer, and to indicate this area to the user. In this way, the convenience for the user can be improved. For example, FIG.
As shown in the example of the appearance of the above, the communication recommended area R1 is provided at the position of the outer surface corresponding to between the segments 14a and 14b constituting the information communication antenna 14 provided inside, so that the user can place the IC in the area R1. Hold card 3
High-quality information communication can be performed between the reader / writer 2 and the IC card 3.

Also, for example, regarding the information communication antenna 14 of the reader / writer 2 shown in FIG. 8, when the recommended communication area R2 is provided at the position of the outer surface corresponding to the three segments 14e, 14f, and 14g, FIG. 14 shows an example of the appearance of the reader / writer 2 from FIG. As described above, it is most preferable that the IC card is held over the reader / writer between the segments constituting the information communication antenna of the reader / writer.

In the case where the IC card is held outside the segment constituting the information communication antenna of the reader / writer and the magnetic flux generated from the IC card is positioned so as to penetrate all the segments in the same direction, As described above, the influence of the magnetic flux generated from the IC card on the information communication antenna of the reader / writer is reduced. Therefore, only when the user needs it, that is,
Information communication is realized only when the IC card is held over the communication recommended area.

As described above, for example, in a reader / writer,
By indicating the recommended communication area on its outer surface or the like, the user can hold the IC card over a certain position (the recommended communication area), thereby performing high-quality information communication with the IC card. Has been realized. In addition, by holding the IC card over the recommended communication area,
Information communication can be reliably performed between the IC card and the reader / writer, and from such a point, convenience is improved.

Also, for example, when the antenna arrangement of the present invention is applied to both a reader / writer and a moving object such as a tag, and both of them have the antenna arrangement shown in FIG. Power can be transmitted to and from the moving object using the respective power transmission antennas, and information communication can be performed using the respective information communication antennas. That is, for power transmission, electromagnetic coupling may be generated between the power transmission antennas, and for information communication, electromagnetic coupling may be generated between the information communication antennas.

Here, in the above-described embodiment, in the reader / writer, by arranging the power transmission antenna and the information communication antenna at right angles in the same plane, it is possible to prevent interference between both antennas, By disposing the coil constituting the antenna into multiple segments, etc.,
Although the influence of the magnetic flux of the external noise has been reduced, for example, only one of these two antenna arrangements can be applied to a reader / writer or a moving body. When both of these antenna arrangements are applied as in this example,
It is possible to more reliably ensure the quality of information communication and the like.

In a case where a reader / writer or a mobile body does not use an arrangement in which the power transmission antenna and the information communication antenna are orthogonal to each other in the same plane, for example, both antennas are shared by one antenna. You can also. In addition, for example, the influence of the magnetic flux of external noise can be reduced by dividing the coil constituting the power transmission antenna into a plurality of segments. And the like.

Further, as shown in FIG. 15, for example, when the coil forming the power transmission antenna 31 is not substantially flat but has a three-dimensional shape, the coil forming the information communication antenna 32 is placed on the same plane. As shown in FIG. 2, all the segments 32 constituting the information communication antenna 32 are arranged on the same plane P orthogonal to the axis of the coil constituting the power transmission antenna 31 as shown in FIG.
a, 32b, 32c, and 32d as well as some segments 3 as shown in FIG.
The segments 2a and 32c and the other segments 32b and 32d can be located on different planes.

That is, for example, the partial segment 3
By arranging the other segments 32a, 32c and the other segments 32b, 32d on the plane Q and the plane W respectively having the same distance from the plane P, substantially all of the segments 32a, 32b, 32c, 32d Are in the same plane P, the same effect can be obtained. As described above, the concept of the same plane includes a case where the surfaces are substantially the same.

[0078]

As described above, according to the reader / writer of the present invention, the power transmission antenna for transmitting power to the mobile unit and the information communication antenna for communicating information with the mobile unit are provided. Since these antennas are arranged so as not to cause mutual interference due to electromagnetic coupling, efficient power transmission, high-quality information communication and the like can be realized. According to the moving body of the present invention, the power transmission antenna for receiving power from the reader / writer and the information communication antenna for communicating information with the reader / writer are electromagnetically coupled between the two antennas. Therefore, since the arrangement is made such that mutual interference does not occur, efficient power transmission, high-quality information communication and the like can be realized.

Further, according to the reader / writer of the present invention, since the information communication antenna for communicating information with the mobile object is arranged so as to reduce the influence of the antenna on the magnetic flux of the external noise, the height is high. High quality information communication and the like can be realized. Also, according to the reader / writer according to the present invention, since a communication recommended area suitable for holding a moving object is provided, for example, a user can perform high-quality information communication between the reader / writer and the moving object. It is possible to improve user convenience and the like. According to the reader / writer of the present invention, it is also possible to reduce the influence of the magnetic flux of external noise on the information communication antenna based on the fact that the voltage induced in the coil by the magnetic flux depends on the winding direction of the coil. Thus, high-quality information communication can be realized in this manner.

Further, according to the moving body of the present invention, since the information communication antenna for communicating information with the reader / writer is arranged so as to reduce the effect of the antenna on the magnetic flux of the external noise, the height is high. High quality information communication can be realized. According to the IC card system according to the present invention, in the reader / writer, the information communication antenna for communicating information is arranged so as to reduce the influence of the antenna on the magnetic flux of external noise, and the information communication antenna And a power transmission antenna for transmitting power are arranged so that mutual interference does not occur due to electromagnetic coupling between these two antennas, so that efficient power transmission and high-quality information communication can be more reliably performed. Can be realized.

[Brief description of the drawings]

FIG. 1 is a configuration example of an IC card system according to an embodiment of the present invention.

FIG. 2 is a diagram showing a schematic configuration of a reader / writer.

FIG. 3 is a diagram illustrating an example of an antenna arrangement of a reader / writer.

FIG. 4 is a diagram illustrating an antenna arrangement according to the present invention.

FIG. 5 is a diagram illustrating an antenna arrangement according to the present invention.

FIG. 6 is a diagram illustrating an arrangement of an information communication antenna according to the present invention.

FIG. 7 is another arrangement example of the information communication antenna.

FIG. 8 is another arrangement example of the information communication antenna.

FIG. 9 is a diagram showing a schematic configuration of an IC card.

FIG. 10 is a diagram for explaining power transmission between a reader / writer and an IC card.

FIG. 11 is a diagram for explaining information communication between a reader / writer and an IC card.

FIG. 12 is a diagram for explaining information communication between a reader / writer and an IC card.

FIG. 13 is an example of a communication recommended area provided in a reader / writer.

FIG. 14 is an example of a communication recommended area provided in a reader / writer.

FIG. 15 is an example of an antenna arrangement.

FIG. 16 is an example of an antenna arrangement.

FIG. 17 shows an arrangement of a power transmission antenna and an information communication antenna according to a conventional example.

FIG. 18 is a side view of an antenna arrangement according to a conventional example.

[Explanation of symbols]

2 .... reader / writer, 3 .... IC card, 13, 21
..Power transmission antennas, 14, 22 ... information communication antennas, 14a, 14b, 14c, 14d, 14
e, 14f, 14g ··· segment, R1, R2 ··· recommended communication area, φ1, φ2, φ3, φ4 ··· magnetic flux, A,
B, C, D, terminals, 31 antennas for power transmission,
32 ··· Information communication antenna, 32a, 32b, 32
c, 32d segment, i1, i2, i3 ... current,

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Mitsuhiro Okada 3- 14-20 Higashi-Nakano, Nakano-ku, Tokyo Kokusai Denki Co., Ltd. (72) Inventor Manabu Nakamura 3- 14-20, Higashi-Nakano, Nakano-ku, Tokyo Kokusai Electric Inside the corporation

Claims (7)

[Claims] 1. A reader / writer for transmitting power to a mobile using an antenna for power transmission and communicating information with the mobile using an antenna for information communication, the reader / writer comprising: A reader / writer, wherein an antenna and the information communication antenna are arranged on the same plane, and axes of coils constituting both antennas are orthogonal to each other. 2. A mobile body that receives power from a reader / writer using an antenna for power transmission and performs information communication with the reader / writer using an antenna for information communication. A moving body, wherein an antenna and the information communication antenna are arranged in the same plane, and axes of coils constituting both antennas are orthogonal to each other. 3. A reader / writer which communicates information with a mobile body using an information communication antenna, wherein a coil constituting the information communication antenna is divided into a plurality of segments, and one of the coils is divided by a magnetic flux of external noise. A reader / writer arranged so that a voltage induced in a segment of a part and a voltage induced in another segment are offset. 4. The reader / writer according to claim 3, wherein a communication recommended area for providing information communication with the moving object by holding the moving object between the segments is provided. . 5. The reader / writer according to claim 3, wherein a winding direction of a coil of the partial segment is opposite to that of the other segment. 6. A mobile body that communicates information with a reader / writer using an information communication antenna, wherein a coil constituting the information communication antenna is divided into a plurality of segments, and one of the coils is divided by a magnetic flux of external noise. A moving body characterized in that a voltage induced in a segment of a part and a voltage induced in another segment are arranged so as to cancel each other. 7. An IC card system for transmitting power from a reader / writer to an IC card using a power transmission antenna and communicating information between the reader / writer and the IC card using an information communication antenna. In the reader / writer, a coil constituting the information communication antenna is divided into a plurality of segments in the same plane, and a voltage induced in some segments by a magnetic flux of external noise and another segment are used. The antennas for power transmission and the antenna for information communication are arranged in the same plane, and the axes of the coils constituting these antennas are mutually aligned. An IC card system characterized by being orthogonal.