JPH1132452A - Reader and/or writer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure a good communication by providing a main coil and a spiral antenna generating an electromagnetic field performing both operating power supply to an IC card and transmission/reception of communication signal thereby enlarging the communication enabling range while satisfying the radiation field level regulated by the Wireless Telegraphy Act. SOLUTION: Direction of a current flowing through an auxiliary coil or a spiral antenna (hereinafter, referred to SA) 6 is set identical to that of a current flowing through a main coil or an SA 5. Direction of a current flowing through the auxiliary coil or an SA 7 is set reverse to that of a current flowing through the auxiliary coil or the SA 6. Since the majority of a field 8 induced by the main coil or the SA 5 is attracted by a pair of auxiliary coils or SA 6, 7, the field strength is weakened through cancellation at the remote site. Consequently, the radiation field level regulated by the Wireless Telegraphy Act is satisfied and the communicable range can be widened by elevating the upper limit of current being fed through the main coil or the SA 5.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cash dispenser, electronic money, an automatic ticket gate system, a cash card, a credit card, a boarding pass, a commuter pass, a coupon, a management card, an ID card, a license card in an entrance / exit management system and the like. The present invention relates to a reader and / or writer device for performing power transmission and communication for proximity wireless operation with a proximity wireless card such as a certificate.

[0002]

2. Description of the Related Art Conventionally, non-contact power supply from a power supply side to a proximity wireless card (IC card) using light or a magnetic field is disclosed in Japanese Patent Application Laid-Open Nos. 7-85233 and 9-62816. No. 1993, which is hereby incorporated by reference.

[0003]

A cash card, a credit card, a ticket, a commuter pass, and the like used at a ticket gate of a station, a bus, an entrance / exit, and the like are converted into an IC card.
When the user passes the card without contact with the reader / writer provided at the ticket gate of the station, the bus, the entrance, etc.
A contactless card system (proximity) that radiates a power transmission wave or communication wave from a coil or antenna of a reader / writer, receives and induces this electromagnetic wave by a coil or antenna on a card side, operates a circuit on a card side, and detects a signal. In a wireless card system, the electric field radiated from the coil or antenna of the reader / writer must satisfy the regulation value by the Radio Law (500 μV / m at a distance of 3 m). However, the upper limit of the current value of the coil for the reader / writer or the antenna is determined by the regulation value of the radiated electric field by the radio law (500 μV / m at a distance of 3 m), and accordingly, the strength of the magnetic field required for power transmission and communication is determined. Since the upper limit is determined, there is a problem that the communicable range is limited.

The prior art disclosed in Japanese Patent Application Laid-Open No. 9-212606 is provided with three or more loop coils, and each of the plurality of loop coils is provided with a carrier having a predetermined frequency and different phases by using a phase shifter. A non-contact reader / writer which applies a signal and cancels out electromagnetic fields in a distant place to suppress the influence of radiation on peripheral devices is described. However, in the case of this conventional technique, a waveform in which the magnetic fields generated from the respective coils are overlapped is supplied to the card, and as a result, the overlapped waveform is deformed such that the width of the waveform is wider than the expected basic waveform. This makes it difficult to transmit accurate information.

[0005] An object of the present invention is to solve the above problems.
Radiated electric field regulation value of radiation electric field (500μ at 3m distance)
V / m) and a communicable range, that is, a communicable distance of the close proximity wireless card (IC card) from the reader / writer can be extended to perform good communication in the proximity wireless card system. And / or to provide a writer device.

[0006]

In order to achieve the above object, the present invention provides an electromagnetic field for supplying both operating power to an IC card and transmitting or transmitting a communication signal to and from the IC card. And / or a writer device provided with a main coil or a spiral antenna for generating a signal. The present invention also relates to a reader and / or writer device for both supplying operating power to an IC card and transmitting or transmitting a communication signal, wherein a plurality of coils or spiral antennas have the same or opposite phases or opposite phases. By distributing currents in the same phase in the direction, magnetic fields that are components that are out of phase with each other are generated.
It is characterized by having an antenna that enables power transmission and good communication in very close areas that do not interfere with each other, and that suppresses a radiated electric field because they interfere with each other and cancel each other out in distant places. With this configuration, the communicable range can be greatly expanded while complying with the Radio Law, or the communicable range can be controlled.

Further, the present invention is a reader and / or writer device for performing both supply of operating power to an IC card and transmission or transmission of a communication signal, and generates an electromagnetic field for both the supply and the power supply. A main coil or a spiral antenna, and an auxiliary coil or a spiral antenna for generating a magnetic field having a phase opposite to that of the magnetic field generated by the main coil or the spiral antenna to suppress the electromagnetic field strength at a distant place. . The present invention is also a reader or / and writer device for performing both the supply of operating power to an IC card and the transmission or transmission / reception of a communication signal, and a main coil or a writer device for generating an electromagnetic field for both or power supply. It is characterized by comprising a spiral antenna, and an auxiliary coil or a spiral antenna that generates an axial magnetic field in a direction opposite to a magnetic field generated by the main coil or the spiral antenna and suppresses electromagnetic field strength at a distant place.

Further, the present invention is characterized in that in the reader or / and writer device, power is supplied to the main coil or the spiral antenna and the auxiliary coil or the spiral antenna in different phases. Further, the invention is characterized in that, in the reader or / and writer device, the main coil or the spiral antenna and the auxiliary coil or the spiral antenna have different winding directions. Also, in the present invention, in the reader or / and writer device, the phase of the power transmission wave is made different for each of the main coil or the spiral antenna and the auxiliary coil or the spiral antenna, and the signal wave is made in the same phase. Power is supplied.

The present invention also relates to an IC card for an IC card.
A reader and / or writer device for both supplying operating power to a card and transmitting or transmitting a communication signal, comprising: a main coil or a spiral antenna for generating an electromagnetic field for both or power supply; A reader or / and writer device characterized in that an auxiliary coil or a spiral antenna for suppressing a distant electromagnetic field intensity generated by a coil or a spiral antenna is arranged in parallel. The present invention also relates to a reader and / or writer device for performing both supply of operating power to an IC card and transmission or transmission of a communication signal between the IC card and the IC card. A reader or / and writer device characterized in that a main coil or a spiral antenna for generating a field and an auxiliary coil or a spiral antenna are juxtaposed to expand a horizontal area of a magnetic field intensity distribution. Further, the present invention is characterized in that in the reader or / and writer device, power is supplied by varying the amplitude of a current flowing to each of the main coil or spiral antenna and the auxiliary coil or spiral antenna.

[0010] The present invention also relates to an IC card and an IC card.
A reader and / or writer device for both supplying operating power to a card and transmitting or transmitting a communication signal, comprising a coil or a spiral antenna for generating an electromagnetic field for both or power supply, and the coil Alternatively, the winding direction is reversed at a phase inversion portion of a current distribution on a spiral antenna line, the phase of the current on the line is inverted, and the phase of the axial magnetic field is in-phase. It is.

Further, according to the present invention, in the reader or writer apparatus, a power supply for generating a signal for power transmission, an encoding circuit for encoding input transmission data, and the power supply are provided. A modulator that amplitude-modulates and superimposes a signal obtained from an encoding circuit on a signal, and a power supply circuit that feeds the main coil or the spiral antenna and the auxiliary coil or the spiral antenna based on the signal obtained from the modulator And characterized in that:

Further, according to the present invention, in the reader or writer device, a power supply unit for generating a signal for power transmission, an encoding circuit for encoding input transmission data, and the power supply unit are provided. A modulator for amplitude-modulating and superimposing a signal obtained from an encoding circuit on the signal, and a power supply circuit for feeding power to the coil or the spiral antenna based on the signal obtained from the modulator. . The present invention also provides the reader or / and the writer device, wherein a power supply for generating a signal for power transmission, a modulator for modulating a signal obtained from the power supply,
A power supply circuit for supplying power to the main coil or the spiral antenna and the auxiliary coil or the spiral antenna based on a signal obtained from the modulator.

With the configuration described above, the electric field strength at a distant place can be suppressed, and a large current can be passed while complying with the Radio Law. Therefore, the magnetic field strength near the reader / writer device is increased, and the communication range is improved. It is possible to expand.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments according to the present invention will be described with reference to the drawings. First, the cash dispenser,
For non-contact cards such as cash cards, credit cards, tickets, commuter passes, coupons, management cards, ID cards, licenses, etc. in electronic money, automatic ticket gate systems, entrance / exit management systems, etc. and non-contact card operations in reader / writers A power transmission system and a communication antenna used for the power transmission system will be described. FIG. 1 is a block diagram showing a reader / equipment provided at a ticket gate, a bus, an entrance / exit, or a predetermined place according to the present invention.
FIG. 2 is a diagram showing a schematic configuration of a power transmission and communication system for wirelessly transmitting power and communicating with a non-contact card (proximity wireless card: IC card) 2 passed or approached by a writer 1 in a non-contact manner. The non-contact card (proximity wireless card: IC card) 2 is held by the user and separated from the reader / writer 1 provided at the ticket gate, bus, or entrance / exit by a distance of, for example, about 20 cm without contact. The information is transmitted and received using a wireless communication, such as a cash card, a credit card, a ticket, a commuter pass, and serves as a cash card, a credit card, a ticket, a commuter pass, and the like.

FIG. 2 is a block diagram showing a configuration in which power is transmitted wirelessly between a reader / writer 1 according to the present invention and a non-contact card (proximity wireless card: IC card) 2 and information is transmitted / received (communicated) wirelessly. FIG. 1 is a configuration diagram illustrating an embodiment of an apparatus (system) for performing the above. In the embodiment shown in FIG. 2, the R / W provided in the R / W unit 1
Between the coil 101 and the card coil 201 formed on the close proximity wireless card 2, both power transmission and communication transmission / reception are performed using an electromagnetic wave (wireless) composed of a power transmission wave and a data communication modulation wave shown in FIG. This is a case where the operation is performed. As described above, the power transmission wave and the signal wave in the ASK modulation method have different frequency components when viewed in the frequency domain. However, when viewed in the time domain, the amplitude of the power transmission wave only changes according to the signal speed. That is, in the time domain, the modulated wave obtained by multiplying the power transmission wave by the signal wave looks only as if the waveform amplitude of the power transmission wave fluctuates up and down. When this is transmitted wirelessly, it is conceivable that the power transmission wave and the signal wave are transmitted by different antennas. However, in the present invention, the contactless card (proximity wireless card: IC card) 2
In order to simplify the above, the electric field intensity is limited within the radio law (500 μV / m at a distance of 3 m), and the modulated wave is transmitted by a single antenna (R / W coil) 101.

That is, the R / W (reader or / and writer) unit 1 has a power supply 105 for generating a high-frequency voltage of 13.56 MHz, and input data (DATA) 106 to be transmitted to the proximity wireless card 2. 13. An encoding circuit 107 for encoding.
The coding circuit 107 is placed on a high frequency voltage of 56 MHz.
Amplitude modulation (Amplitude Shift Keyi
ng modulation), and the modulator 108
The transmission amplifier 109 amplifies a signal ASK-modulated on a high-frequency voltage of 13.56 MHz, and the signal amplified by the transmission amplifier 109 is coupled by an inductance coupling 103, and the impedance is matched by having a capacitor 104. And a matching circuit (feeding circuit) 102 for preventing reflection and generating an electromagnetic wave for transmitting power and transmitting data in accordance with the output of the matching circuit 102, and from a card coil 201 of the proximity wireless card 2. An R / W coil 101 for receiving data transmitted by an electromagnetic wave, and a filter circuit 110 for matching a signal received by the R / W coil 101 with a matching circuit 102 and removing a noise component from a signal generated by the inductance coupling 103. And a reception amplifier for amplifying a signal obtained through the filter circuit 110. And 111, 13.56M obtained the signal amplified by the receiving amplifier 111 from the power supply 105
Demodulator 11 that demodulates using a high-frequency voltage signal of 1 Hz
2 and a decoding circuit 113 for decoding the signal demodulated by the demodulator 112 and outputting it as received data (DATA) 114.

The proximity wireless card (contactless card: IC card) 2 receives an electromagnetic wave generated for transmitting power and transmitting data from the R / W coil 101 of the R / W unit 1 and performs load switching modulation. A card coil 201 that generates an electromagnetic wave according to the transmitted data, and a matching / rectifying circuit 203 that rectifies 13.56 MHz power received by the card coil 201 and matches an impedance of the transmission / reception signal by matching the impedance. 5 from the induced voltage rectified from the matching / rectifying circuit 203
a power supply circuit 204 for supplying a constant DC voltage power supply 205 of about 2 to 5 V at about mW and the matching / rectifying circuit 20;
3 and a LPF circuit 20 for removing a noise component from the received signal obtained from the matching and rectifying circuit 203.
7, a waveform shaping circuit 208 for shaping the waveform of the reception signal obtained from the LPF circuit 207, and a load switching modulation circuit for load switching modulating the transmission signal and supplying the modulated signal to the matching / rectifying circuit 203 for matching and supplying it to the card coil 201. 209, a frequency dividing circuit 211 for generating a signal for operating the microcomputer 214 by dividing the frequency based on the clock signal extracted by the clock extracting circuit 206 of the wireless chip 202, and a waveform shaping of the wireless chip 202. A decoding circuit 212 for decoding a signal obtained from the circuit 208, a reception data control circuit 213 for controlling decoded data (reception data) obtained from the decoding circuit 212 and inputting the data to the microcomputer 214, and transmission data from the microcomputer 214. Data control circuit 215 obtained by controlling the A built-in encoding circuit 216 that encodes transmission data obtained by controlling from 215 and inputs the encoded data to the load switching modulation circuit 209 of the wireless chip 202 and a memory that stores information as a card, and performs processing of transmission / reception data and memory. H8 for transferring data between
And a CPU + interface chip 210 which receives a stable power supply 205 from the power supply circuit 204 of the wireless chip 202.

The reason why the R / W coil 101 and the card coil 201 are used to transmit power by electromagnetic waves (wireless) is to improve the efficiency of power transmission in the vicinity. Further, when the coil 201 is formed on the close proximity wireless card 2, there is an advantage that the close proximity wireless card 2 is strong against deformation. Further, both the R / W coil 101 and the card coil 201 may be formed by a spiral antenna. As explained above,
In the proximity wireless card system, a contactless card (proximity wireless card:
By bringing the (IC card) 2 close to each other, power is wirelessly transmitted between the reader / writer 1 and the non-contact card 2, and information is transmitted and received (communication) wirelessly.
Will be performed. That is, in the close proximity wireless card system, a power transmission wave or a communication wave is radiated by the coil for the reader / writer or the spiral antenna 101, and the coil or the spiral antenna 2 on the card side is radiated.
01, the electromagnetic wave is received and induced, the card side circuit is operated, and a signal is detected.

As the coil or spiral antenna 101 used in the reader / writer 1, for example, FIG.
Also, when formed as indicated by 11 in FIG. 18, the current distribution 13 on the antenna is considered to be substantially a -like distribution with respect to the wavelength 22 m determined by the used frequency 13.56 MHz. Therefore, an electric field 14 is generated strongly in the side direction of the antenna, and a magnetic field 15 is generated in the vertical direction. In this case, a vertical coil or spiral antenna 2
When the contactless card 2 on which the 01 is mounted is brought in, power transmission waves or signal waves can be transmitted and received. However, if the radiated electric field is restricted within the regulation value of the Radio Law (500 μV / m at a distance of 3 m), the upper limit of the current value 13 of the coil for the reader / writer or the spiral antenna 11 is determined, and accordingly, the upper limit of the electric power transmission and communication is required. The upper limit of the strength of the magnetic field 15 is determined, and the communicable range is limited. Therefore, a coil or a spiral antenna 101 used for the reader / writer 1 needs to have a radiated electric field that satisfies the regulation value of the Radio Law (500 μV / m at a distance of 3 m) and can expand the communicable range. .

Next, the radiated electric field according to the present invention satisfies the regulation value of the Radio Law (500 μV / m at a distance of 3 m) and the coil provided in the reader / writer 1 capable of expanding the communicable range. Spiral antenna 1
The first embodiment will be described. When a coil or a spiral antenna for power transmission and a coil or a spiral antenna for transmitting or transmitting or receiving a signal for communication are separately provided, in particular, the condition for power transmission is stricter and the condition for power transmission is more severe. In the coil or spiral antenna 101, the radiated electric field needs to satisfy the regulation value of the Radio Law (500 μV / m at a distance of 3 m).

FIG. 4 is a diagram showing a basic configuration of a coil or spiral antenna 101 provided in the reader / writer 1 according to the present invention. Reference numeral 5 denotes a coil or a spiral coil of the spiral antenna 101 for generating an electromagnetic wave for transmitting power and transmitting data. 6 and 7 are provided outside the main coil or the spiral antenna 5 so that most of the magnetic field 8 generated by the main coil or the spiral antenna 5 is drawn so as not to spread to a distant place and the electromagnetic field strength is suppressed at a distant place. 2) shows a pair of auxiliary coils or spiral antennas installed in FIG. The direction of the current flowing through the auxiliary coil or the spiral antenna 6 is the same as the direction of the current flowing through the main coil or the spiral antenna 5. The direction of the current flowing through the auxiliary coil or the spiral antenna 7 is opposite to the direction of the current flowing through the auxiliary coil or the spiral antenna 6.
As a result, as shown in FIG. 5, much of the magnetic field 8 generated by the main coil or the spiral antenna 5 is drawn by the pair of auxiliary coils or the spiral antennas 6 and 7, and the electric field strength at a distant place is canceled out. Radiated electric field is regulated by the Radio Law (distance 3m
In this case, the upper limit of the value of the current flowing through the main coil or the spiral antenna 5 can be increased to expand the communicable range. That is,
As shown in FIG. 6, most of the magnetic field 8 generated by the main coil or the spiral antenna 5 is drawn by the pair of auxiliary coils or the spiral antennas 6 and 7, and the electromagnetic field strength is canceled and suppressed at a distant place. In the vicinity, the electromagnetic field generated by the main coil or the spiral antenna 5 is generated so as to be wrapped. Even if the value of the current flowing through the main coil or the spiral antenna 5 is increased to increase the electromagnetic field, the regulation of the Radio Law The value (500 μV / m at a distance of 3 m) can be satisfied. As a result, the communicable range and the distance separating the close proximity wireless card 2 from the reader / writer 1 can be increased.

Next, an embodiment of a coil or a spiral antenna 101 provided in the reader / writer 1 according to the present invention and having a reduced electromagnetic field intensity at a distance will be described with reference to FIG. That is, the antenna 101a is composed of the main part 28 in which the current winding directions are opposite to each other and the auxiliary part 29 installed around the main part 28, so that the magnetic field 26a generated from each of these parts 28, 29 27b is in opposite phase and cancels out at a distance. Further, by giving the canceling auxiliary coil or the spiral antenna 29 a very small width compared to the wavelength determined by the frequency to be used, the coil or the spiral antenna 29
Currents 22a, 24a flowing in
As a result, the electric fields 23a and 25a generated by the respective currents 22a and 24a also become opposite to each other and cancel each other. Similarly, an electric field 23b due to a current 22b flowing through the central main coil or spiral antenna 28,
Auxiliary coil for cancellation or spiral antenna 29
The electric field 25b caused by the current 24b flowing in the opposite direction also becomes opposite to each other, and cancels each other. As a result, the electric field strength at a distance cancels out and weakens, and the upper limit value of the current flowing through the main coil or the spiral antenna 28 for complying with the Radio Law can be increased, thereby expanding the communicable range. it can. Here, although the magnetic field is canceled similarly, the card side coil or the spiral antenna 20 near the center main coil or the spiral antenna 28 near the center main coil or the spiral antenna 28 due to the directivity synthesis of the antenna.
1a is a central main coil or spiral antenna 2
8, the card-side coil or the spiral antenna 201b is combined with the magnetic field 26a generated by the center coil or the spiral antenna 28 and the canceling auxiliary coil or the magnetic field 27a generated by the spiral antenna 29 in a distant upper part. From the detection of the components, it can be seen that they become weaker.

Accordingly, the antenna 101 of the present embodiment
17A generates a large magnetic field in the vicinity as compared with the antennas shown in FIGS. 17 and 18, and can comply with the Radio Law at a long distance, indicating that the antenna is suitable for a card reader / writer. Furthermore, a coil or a spiral antenna 1 provided in the reader / writer 1 according to the present invention.
An embodiment as the further improved far electromagnetic field canceling antennas I101b and II101c as 01 will be described with reference to FIGS. An antenna (distant electromagnetic field canceling antenna I) 101b shown in FIG. 8 generates a magnetic field 26a by a central main coil or a spiral antenna 36 to perform power transmission and communication. 3m radiation
In order to make the distance fall within the regulation value of the Radio Law, an oppositely-wound antenna 37 is used to generate an anti-phase magnetic field 27b. Thereby, the magnetic fields vertically above the antenna 101b cancel each other. As for the electric field in the side direction, the electric field 33 generated by the center main coil or the side 32a of the spiral antenna 36 is equal to the side 34 of the auxiliary antenna 37 wound in the reverse direction.
The electric field 35a generated by a and the electric field 35b generated by the side 34b are canceled in each direction. From the above,
Since the magnetic field 26b generated by this antenna is dominant near the center main coil or the spiral antenna 36, power transmission and communication are enabled by this magnetic field 26b, and the electromagnetic field 27b by the reverse winding auxiliary antenna 37 is distant in the distance. As a result, power transmission and communication can be performed in the vicinity while satisfying the Radio Law at a distance of 3 m.

The antenna (distant electromagnetic field canceling antenna II) 101c shown in FIG. 9 is the same as the antenna 101 shown in FIG.
The magnetic field 26a radiated in the side direction without the auxiliary antenna 29 having the opposite phase at the side a is canceled out by weakening the magnetic field 27a having the opposite phase by preparing the auxiliary antenna 29 'having the opposite phase also in this side direction. Have. Here, the electric field emission in the lateral direction is canceled out by the electric field 45 emitted by the current 44 flowing on the side of the anti-phase auxiliary antenna 29, and the electric field 43 emitted by the current 42 flowing on the side of the main antenna 28 at the center. Current 46 flowing on the side of the anti-phase auxiliary antenna adjacent to the anti-phase auxiliary antenna
Only electric fields 47a and 47b radiated by a and 46b are provided. Therefore, the electric field in the side direction can be reduced as compared with the antenna having a simple loop shape, and the magnetic field leaking to the side surface can be suppressed as compared with the case of the shape shown in FIG. The antenna (distant electromagnetic field canceling antenna III) 101d shown in FIG. 10 is an anti-phase antenna 2 that generates electric fields 47a and 47b in the lateral direction in the case shown in FIG.
9 against the currents 46a and 46b flowing through the side 51
The generation of an electric field is suppressed by flowing a reverse current with the side 51 'of the anti-phase auxiliary antenna 29' adjacent to 1 being opposed. In this case, the electric field in the side direction is the electric field 43 generated by the current 42 flowing on the side of the main antenna 28 at the center and the current 44 flowing on the side of the antiphase auxiliary antenna 29 ′
Since the electric fields 45 generated by each other cancel each other, the electric field in the side force direction can be suppressed as compared with the antenna 101c shown in FIG.

The antenna (distant electromagnetic field canceling type antenna IV) 101e shown in FIG. 11 is the same as the antenna 1 shown in FIG.
01d has a shape in which adjacent sides of the anti-phase antennas are omitted, and is formed by a combination of a central main coil or spiral antenna 28 and an auxiliary coil or spiral antenna 29 "that generates an anti-phase magnetic field. Is generated in the antenna 101d shown in FIG.
10, the antenna 101d shown in FIG. 10 has a main coil or spiral antenna 28 at the center and coils or spiral antennas 29 having opposite phases to each other.
29 'can be fed independently, so that the antenna line length can be sufficiently shortened, whereas the antenna structure shown in FIG.
Is a single structure, so the line length becomes longer. However, when the wavelength determined by the used frequency 13.56 MHz is sufficiently long and the line length of the antenna is sufficiently short, the structure is simple and the manufacturing cost can be reduced.

An antenna (distant electromagnetic field canceling antenna V) 101f shown in FIG. 12 includes an antiphase auxiliary coil or a spiral antenna 29 prepared to cancel a distant magnetic field generated by a central main coil or a spiral antenna 28. In order to further cancel the leakage of the magnetic field due to 29 'in the side direction of the reader / writer, the main coil or spiral antenna 28 at the center and the auxiliary coil or spiral antenna 30 excited in phase are combined. In the antenna 101f, the magnetic field generated by the central main coil or the spiral antenna 28 is opposite in phase to the auxiliary coil or the spiral antenna 2.
Auxiliary coil or spiral antenna 2 which is canceled by 9 and 29 'at the top, but in opposite phase on the outside of the side
The magnetic field generated by 9, 29 'remains. In order to cancel this, an auxiliary coil or a spiral in the same phase as the main coil or the spiral antenna 28 at the center, which generates a magnetic field having a phase opposite to the magnetic field generated by the anti-phase auxiliary coil or the spiral antenna 29, 29 ' An antenna 30 is prepared. Here, since the distance between the opposite sides 84 and 85 of the auxiliary coil or spiral antennas 29 and 29 ′ in opposite phase to the center main coil or spiral antenna 28 is narrow, the coil or spiral prepared further outside the side surface The interval between the opposing sides 86 and 87 in the antenna 30 can be reduced, and the electric field radiated to the outside of the side surface can be effectively canceled out. As a result, the electric field outside the side surface can also be suppressed.

The antenna (distant electromagnetic field canceling antenna VI) 101g shown in FIG. 13 is the same as the antenna 1 shown in FIG.
The same effect as 01f is shown, and the whole antenna is formed of a continuous line, and becomes a single feed. This is similar to the antenna 101e shown in FIG. 11, and when the line length becomes longer than the wavelength determined by the frequency used, the current on the line undergoes phase inversion, the electromagnetic field distribution is disturbed, and the canceling effect is weakened. However, if the line length is sufficiently short with respect to the wavelength, the same effect as that of the antenna 101f shown in FIG. 12 is obtained, and the structure is simple, so that the manufacturing cost can be reduced.

An antenna (distant electromagnetic field canceling antenna VII) 101h shown in FIG. 14 has a plurality of coils or spiral antennas 61a, 61b and 61c, and mutually excites opposite phases as indicated by 61a, 61b and 61c. Or, the antenna has the current direction reversed. Thus, for example, in the case of three coils or spiral antennas 61a, 61b, 61c, the magnetic field 66a generated by the coil is dominant immediately above the center main coil or spiral antenna 61a, Magnetic fields 66b and 66c generated by the auxiliary coils or spiral antennas 61b and 61c whose current directions are close to each other in the opposite direction cancel each other upward in the magnetic field 66a generated by the main coil or the spiral antenna 61a at the center, and the electric field in the side direction is also the same. Therefore, it is possible to generate a strong magnetic field in the vicinity as compared with a single coil while satisfying the Radio Law. That is, power is supplied to the auxiliary coil or the spiral antennas 61b and 61c which are close to (adjacent to) the main coil or the spiral antenna 61a at different phases from each other (specifically, for example, the opposite phase excitation is performed) to thereby generate the magnetic field 66a. And the magnetic fields 66b and 66c are generated to cancel the magnetic field 66a in the upper distant place, and also cancel the electric field in the side direction in the same way. To be able to In this embodiment, the auxiliary coil or spiral antenna 61b, 6b which is close to (adjacent to) the central main coil or spiral antenna 61a.
1c are arranged one-dimensionally (uniaxially), but as shown in FIGS. 8 to 13, two-dimensionally (biaxially: x,
Obviously, the arrangement may be made in the (y-axis direction).

In the embodiment described above, the magnetic field generated by the main coil or the spiral antenna 28, 61a is not affected by the auxiliary coil or the spiral antenna 29, 2a.
The magnetic fields generated at 9 ', 29 ", 61b, and 61c are reversed in phase or in the opposite axial direction to cancel the magnetic field in the upward distant place, and also cancel the electric field in the lateral direction in the same manner, satisfying the Radio Law. In the vicinity, it is possible to generate a stronger magnetic field as compared with a single coil and expand the communicable range.The antenna (uniform near-field antenna) 101i shown in FIG. Antennas 62a, 62b, 62c
As shown by 9a, 69b and 69c, the antennas are excited in the same phase or have the same current direction. In this embodiment, in order to satisfy the Radio Law, the current flowing through each of the antennas 62a, 62b, and 62c needs to be reduced as compared with the case of the single coil shown in FIGS. Since the magnetic field distribution 71 above the antenna can be made more uniform over a wide lateral area as compared with the case of, the lateral area where communication is possible can be expanded. Especially the outer coil or spiral antenna 62
It is desirable that the current flowing through b and 62c be larger than the current flowing through the center coil or spiral antenna 62a. That is, it is desirable that the amplitude of the current flowing through the outer coil or the spiral antennas 62b and 62c be different from the amplitude of the current flowing through the center coil or the spiral antenna 62a to supply the power.

In the antenna 101i of this embodiment, all the coils or spiral antennas 62
When currents that are not in phase for a, 62b, and 62c are given, it is possible to expand the power transferable area. In this case, the coil or spiral antenna 62a, 62
It is necessary to shift (change) the phase of power transmission to, for example, 0 °, 90 °, and 180 ° with respect to each of 2b and 62c, and feed the communication signal wave in the same phase. That is, the coil or spiral antenna 62a, 62
This is because transmission or transmission / reception cannot be performed unless the communication signal wave is supplied to each of b and 62c in the same phase.
In this embodiment, a case is shown in which the central main coil or spiral antenna 62a and the auxiliary coil or spiral antenna 62b, 62c approaching (adjacent) are arranged one-dimensionally (uniaxially). 13
It is obvious that the array may be arranged two-dimensionally (biaxial directions: x, y-axis directions) as shown in FIG.

The antenna shape shown in FIG. 16 is an embodiment of in-phase excitation. This antenna 101j has a frequency 13.2 used by the line length from the feeding point 81 to the turn-back position 82.
Half length 1 of wavelength 22m determined by 56MHz 1
In the case of using a power supply method which is equal to 1 m or in which the phase inversion of the current occurs at the turning position 82, the power supply point 81
This is a spiral array antenna that utilizes the fact that the magnetic field generated by the line from the turn position 82 to the turn position 82 and the magnetic field generated by the line from the turn position 82 to the ground position 83 have the same phase and strengthen each other. By installing such a spiral array antenna 101j in the reader / writer 1, the magnetic field distribution above the antenna is wider than in the case of the single coil shown in FIGS. 17 and 18, as in the embodiment shown in FIG. It can be made more uniform over the horizontal area, and as a result, it is possible to expand the horizontal area where communication can be performed while satisfying the Radio Law.

[0032]

According to the present invention, a coil or an antenna installed in a reader / writer, particularly for supplying operating power to an IC card, is regulated by the Radio Law.
m By suppressing the electromagnetic field strength at a distant place, it is possible to supply a large amount of power to the card side near the reader / writer while satisfying the Radio Law at a distant place,
As a result, while satisfying the Radio Law, for example, a C of about 5 mW
This has the effect of enabling operation power transmission to an IC card such as a PU that consumes a large amount of power. Further, according to the present invention, an electromagnetic field at a distance of 3 m, which is regulated by the Radio Law, in a coil or an antenna installed in a reader / writer for supplying operating power to an IC card and transmitting or transmitting a communication signal. By configuring to reduce the strength,
A large amount of power can be supplied to the card side near the reader / writer while satisfying the Radio Law while being distant. As a result, operation to a large power consumption IC card such as a CPU of about 5 mW while satisfying the Radio Law can be achieved. This has the effect of enabling power transmission.

According to the present invention, the upper magnetic field distribution is made more uniform over a wide lateral area, particularly in a coil or an antenna installed in a reader / writer and for supplying operating power to an IC card. It is possible to expand the horizontal area in which communication is possible, and as a result, it is possible to transmit operating power to an IC card such as a CPU with a large power consumption of, for example, about 5 mW while satisfying the Radio Law. Further, according to the present invention, in a coil or an antenna installed in a reader / writer for supplying operating power to an IC card and transmitting or transmitting a communication signal,
The upper magnetic field distribution can be made more uniform over a wide lateral area, thereby expanding the communicable lateral area. As a result, while satisfying the Radio Law, the power consumption of a CPU or the like of, for example, about 5 mW is reduced. This has the effect of enabling the transmission of operating power to a large IC card.

[Brief description of the drawings]

FIG. 1 is a schematic configuration perspective view showing a power transmission / communication system in which power is wirelessly transmitted between a reader / writer device according to the present invention and a close proximity wireless card (IC card) and wireless communication is performed.

FIG. 2 is a configuration diagram showing an embodiment of a device (system) that wirelessly transmits power and performs wireless communication between a reader / writer device and a close proximity wireless card (IC card) according to the present invention. .

FIG. 3 is a diagram showing a relationship between a power transmission wave and a data communication modulation wave according to the present invention.

FIG. 4 is a perspective view showing a basic configuration of an R / W coil (antenna) installed in the reader / writer device according to the present invention.

5 is a diagram showing a distribution of a magnetic field generated by the basic configuration shown in FIG.

FIG. 6 is a diagram illustrating a state in which the electromagnetic field strength is canceled and suppressed in a distant place by the basic configuration shown in FIG. 4, and the electromagnetic field generated by the main coil or the spiral antenna is generated in a nearby area so as to be wrapped.

FIG. 7 is a perspective view illustrating a basic configuration of an embodiment of an R / W coil (antenna) installed in the reader / writer device according to the present invention.

FIG. 8 is a perspective view showing a far electromagnetic field canceling antenna I which is an embodiment of an R / W coil (antenna) installed in the reader / writer device according to the present invention.

FIG. 9 is a perspective view showing a far electromagnetic field canceling antenna II which is an embodiment of an R / W coil (antenna) installed in the reader / writer device according to the present invention.

FIG. 10 is a perspective view showing a far electromagnetic field canceling antenna III which is an embodiment of an R / W coil (antenna) installed in the reader / writer device according to the present invention.

FIG. 11 is a perspective view showing a far electromagnetic field canceling antenna IV which is an embodiment of the R / W coil (antenna) installed in the reader / writer device according to the present invention.

FIG. 12 is a perspective view showing a far electromagnetic field canceling antenna V which is an embodiment of an R / W coil (antenna) installed in the reader / writer device according to the present invention.

FIG. 13 is a perspective view showing a far electromagnetic field canceling antenna VI which is an embodiment of an R / W coil (antenna) installed in the reader / writer device according to the present invention.

FIG. 14 is a perspective view showing a far electromagnetic field canceling antenna VII which is an embodiment of an R / W coil (antenna) installed in the reader / writer device according to the present invention.

FIG. 15 is a perspective view showing a near-field uniform type antenna which is an embodiment of an R / W coil (antenna) installed in the reader / writer device according to the present invention.

FIG. 16 is a diagram illustrating an antenna shape for in-phase excitation which is an embodiment of an R / W coil (antenna) installed in the reader / writer device according to the present invention.

FIG. 17 is a diagram showing a magnetic field generation state by a single coil as a comparative example of an R / W coil (antenna) installed in the reader / writer device according to the present invention.

FIG. 18 is a diagram showing a single coil as a comparative example of an R / W coil (antenna) installed in the reader / writer device according to the present invention and a magnetic field generation state by the single coil.

[Explanation of symbols]

1 ... Reader / writer unit, 2 ... Proximity wireless card (I
C card: contactless card), 5, 28, 36 ... main coil or spiral antenna, 6, 7, 29, 29 ',
29 ", 30, 37: auxiliary coil or spiral antenna, 61a, 61b, 61c: coil or spiral antenna, 62a, 62b, 62c: coil or spiral antenna, 81: feeding point, 82: folding position, 83: grounding position, 101: R / W coil (antenna), 102: matching circuit (feeding circuit), 105: power supply, 107: coding circuit, 108: modulator, 109: transmission amplifier, 110: filter circuit, 111: reception amplifier, 112 ... demodulator, 113 decoding circuit, 201 card coil, 202 wireless chip, 203 matching / rectifying circuit, 204 power supply circuit, 206 clock extraction circuit,
207: LPF circuit, 209: load switching circuit, 210: CPU + interface chip, 214
… Microcomputer

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Masami Makuuchi 292, Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Prefecture Inside of Hitachi, Ltd. Production Technology Laboratory (72) Ryozo Yoshino 1- 1 Horiyamashita, Hadano-shi, Kanagawa Co., Ltd. Within Hitachi Computer General-purpose Computer Division

Claims (21)

[Claims] 1. A reader and / or writer device for both supplying operating power to an IC card and transmitting or transmitting a communication signal to and from the IC card, wherein the reader and / or the writer device generates both electromagnetic fields. A reader or / and writer device comprising a main coil or a spiral antenna. 2. The reader / writer device according to claim 1, further comprising: generating a magnetic field having a phase opposite to that of the magnetic field generated by the main coil or the spiral antenna to suppress the electromagnetic field strength at a distant place. A reader and / or writer device comprising an auxiliary coil or a spiral antenna. 3. The reader and / or writer device according to claim 1, further comprising: generating an axial magnetic field in a direction opposite to a magnetic field generated by the main coil or the spiral antenna to reduce an electromagnetic field strength at a distant place. A reader or / and a writer device comprising an auxiliary coil or a spiral antenna for suppressing. 4. The reader or the writer device according to claim 2, wherein the main coil or the spiral antenna and the auxiliary coil or the spiral antenna are supplied with power having different phases from each other. And writer equipment. 5. The reader and / or writer device according to claim 2, wherein the main coil or the spiral antenna and the auxiliary coil or the spiral antenna have different winding directions from each other. Writer device. 6. The reader or / and writer device according to claim 2, wherein the power transmission wave has a different phase for each of the main coil or spiral antenna and the auxiliary coil or spiral antenna, and A reader or / and writer device for feeding waves in phase. 7. A reader and / or writer device for both supplying operating power to an IC card and transmitting or transmitting a communication signal to and from the IC card, wherein the reader and / or writer device generates both electromagnetic fields. A reader or / and writer device, comprising: a main coil or a spiral antenna; and an auxiliary coil or a spiral antenna for suppressing a distant electromagnetic field intensity generated by the main coil or the spiral antenna. 8. A reader and / or writer device for both supplying operating power to an IC card and transmitting or transmitting a communication signal to and from the IC card, wherein the reader and / or writer device generates both electromagnetic fields. A reader or / and writer device having a main coil or a spiral antenna and an auxiliary coil or a spiral antenna arranged side by side to expand a horizontal area of a magnetic field intensity distribution. 9. The reader or writer device according to claim 8, wherein power is supplied by varying the amplitude of a current flowing to each of said main coil or spiral antenna and said auxiliary coil or spiral antenna. Reader and / or writer device. 10. A reader and / or writer device for both supplying operating power to an IC card and transmitting or transmitting a communication signal to and from the IC card, wherein the reader and / or writer device generates both electromagnetic fields. With a coil or spiral antenna, the winding direction is reversed at the phase inversion portion of the current distribution on the coil or spiral antenna line,
A reader or / and writer device wherein the phase of a current on a line is inverted and the phase of an axial magnetic field is the same. 11. A reader or / writer apparatus according to claim 2, wherein a power supply section for generating a signal for power transmission, and an encoding circuit for encoding input transmission data. A modulator that amplitude-modulates and superimposes a signal obtained from an encoding circuit on a signal obtained from the power supply unit, and the main coil or the spiral antenna and the auxiliary coil or based on a signal obtained from the modulator. A power supply circuit for supplying power to the spiral antenna. 12. The reader or writer device according to claim 10, wherein a power supply for generating a signal for power transmission, an encoding circuit for encoding input transmission data, and a signal obtained from the power supply. And a power supply circuit for feeding power to the coil or the spiral antenna based on the signal obtained from the modulator. Reader or /
And writer equipment. 13. A reader and / or writer device for performing both operation power supply to an IC card and transmission or transmission of a communication signal to and from the IC card, wherein at least an electromagnetic field for power supply is provided. A main coil or a spiral antenna to be generated, and an auxiliary coil or a spiral antenna for generating a magnetic field having a phase opposite to that of the magnetic field generated by the main coil or the spiral antenna to suppress electromagnetic field strength at a distant place. A reader or / and writer device characterized. 14. A reader and / or writer device for both supplying operating power to an IC card and transmitting or transmitting a communication signal to and from the IC card, wherein at least an electromagnetic field for power supply is provided. A main coil or a spiral antenna to be generated, and an auxiliary coil or a spiral antenna that generates an axial magnetic field in a direction opposite to a magnetic field generated by the main coil or the spiral antenna to suppress electromagnetic field strength at a distance. A reader or / and writer device characterized by the above-mentioned. 15. The reader or / and writer device according to claim 14 or 15, wherein the main coil or the spiral antenna and the auxiliary coil or the spiral antenna are supplied with power having different phases from each other. And writer equipment. 16. The reader and / or writer device according to claim 14, wherein the main coil or the spiral antenna and the auxiliary coil or the spiral antenna have different winding directions from each other. Writer device. 17. A reader and / or writer device for both supplying operating power to an IC card and transmitting or transmitting a communication signal to and from the IC card, wherein at least an electromagnetic field for power supply is provided. A reader or / and writer device wherein a main coil or a spiral antenna to be generated and an auxiliary coil or a spiral antenna are juxtaposed to expand a horizontal area of a magnetic field intensity distribution. 18. The reader / writer device according to claim 17, wherein the power is supplied by varying the amplitude of a current flowing to each of the main coil or the spiral antenna and the auxiliary coil or the spiral antenna. Reader and / or writer device. 19. A reader and / or writer device for both supplying operating power to an IC card and transmitting or transmitting a communication signal to and from the IC card, wherein at least an electromagnetic field for supplying power is provided. It has a coil or spiral antenna that generates, and the winding direction is reversed at the phase inversion part of the current distribution on the coil or spiral antenna line, the current on the line is inverted in phase, and the axial magnetic field is in phase. A reader or / and writer device characterized by the above-mentioned. 20. The reader or writer device according to claim 14, 15 or 17, wherein a power supply for generating a signal for power transmission, a modulation unit for modulating a signal obtained from the power supply, and the modulation unit A feeder circuit for feeding power to a main coil or a spiral antenna and an auxiliary coil or a spiral antenna based on a signal obtained from a reader or a writer device. 21. The reader or writer device according to claim 19, wherein a power supply for generating a signal for power transmission, a modulator for modulating a signal obtained from the power supply, and a signal obtained from the modulator. A feeder circuit for feeding power to a coil or a spiral antenna based on a signal.