JP2000259788A - Contactless IC card system and external read / write device for contactless IC card - Google Patents

Abstract

(57) [Problem] To provide a non-contact IC card, which does not require adjustment of a capacitor capacity for setting a resonance frequency of an antenna circuit composed of a coil and a capacitor, and has a receiving sensitivity to obtain a sufficient communication distance. Provided are a non-contact IC card system and a read / write device of a technology capable of maintaining a practical operation state. In a non-contact IC card system including a non-contact IC card and a read / write device, an external read / write device transmits / receives information to / from a non-contact IC card at a predetermined frequency by a transmitter, an oscillator for generating a carrier frequency, and a data modulator. In addition to the data transmission circuit, a transmission frequency scan function that varies and sweeps the transmission frequency around the frequency specified between the modulator and the data transmission circuit, and the reception unit adds the reception signal to the reception circuit and the demodulation circuit to detect the peak of the reception signal. A receiving frequency seek means for detecting and a receiving frequency auto-tuning function for stopping the sweep of the transmitting frequency when the received signal becomes maximum are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a non-contact information medium, and more particularly, to office automation (so-called OA) and factory automation (so-called F).
A) Or, in an information medium represented by an IC card or the like used in the field of security, etc., power supply power and signal transmission / reception can be performed without providing electrical contacts on the IC card by electromagnetic coupling. The present invention relates to a non-contact IC card performed in a contact state and an external reading / writing device.

[0002]

2. Description of the Related Art With the advent of an IC card having a built-in semiconductor memory or the like, the storage capacity has been dramatically increased as compared with a conventional magnetic card or the like, and an IC card having a built-in semiconductor integrated circuit device such as a microcomputer has been developed. By itself having an arithmetic processing function, it has become possible to impart high security to an information medium.

An IC card is internationally standardized by ISO. Generally, an IC card has a built-in IC such as a semiconductor memory in a card body made of plastic or the like, and has an external reading / writing device on the card surface. A metal conductive terminal is provided for connection, and the IC card is inserted into a card slot of the external read / write device for data communication between the IC card and the external read / write device. This is advantageous in applications requiring certainty and security of communication such as mass data exchange and settlement business, for example, credit and electronic wallet applications.

On the other hand, in application to gate management such as entry and exit, authentication is the main communication content, and the amount of communication data is often small, so simpler processing is desired. A technology devised to solve this problem is a contactless IC card. This is a DC power source that provides a space for vibration energy such as high-frequency electromagnetic fields, ultrasonic waves, and light in space, absorbs and rectifies the energy, and drives an electronic circuit built in the card. The frequency of the component is used as it is, or the frequency is multiplied or divided to provide an identification signal, and the identification signal is transmitted to the information processing circuit of the semiconductor element via an antenna or a coupler such as a coil or a capacitor.

[0005] In particular, many non-contact IC cards for the purpose of authentication and simple counting data processing use wireless authentication of hard logic without a battery and a CPU (Central Processing Unit) (in this specification, simply RF-ID Radio Frequenc
y Abbreviation for IDentification. With the advent of this non-contact IC card, the security against forgery and tampering is improved as compared with the magnetic card, and the card carrier passes the antenna to the antenna section of the external read / write device attached to the gate device when passing through the gate. It is only necessary to bring the card closer or touch the card carried by the antenna unit of the external read / write device, and the complexity for data communication of removing the card from the case and inserting it into the slot of the external read / write device has been reduced.

[0006] Generally, a non-contact IC card has the following configuration. Referring to FIG. 2, a non-contact IC
The card 1 includes a non-contact IC chip 3 mounted on a plastic film formed by etching a metal film by a non-contact transmission mechanism including an antenna or a coil 4 and a resonance capacitor 5 to form an inlet 6 to form a card base 2. Is sealed.

In a non-contact IC card using a short wave band, the constant of a tuning circuit including an antenna or a coil 4 and a resonance capacitor 5 must be accurately determined in order to obtain sufficient communication characteristics. However, the formation of the resonance capacitor 5 using the non-contact IC chip 3 and the plastic film causes large variations in the capacitance value in the manufacturing process.

Conventionally, in manufacturing such a non-contact IC card, the resonance capacitor 5 is trimmed by cutting the lead wire of the capacitance adjusting portion 7 of the resonance capacitor 5 by a punch mechanism after manufacturing the inlet 6. Had been synchronized.

As a result, the cost of the card is increased by the process of adjusting the resonance constant. Furthermore, the burrs caused by the punches had a bad influence on the quality of the card.

On the other hand, in an IC card having both a contact type and a non-contact type function, the IC card comprises an IC module and a card base, and the IC module has a contact type transmission function for the IC card and a non-contact type transmission. It is composed of a composite IC chip having a built-in function, a module substrate having external terminals as a contact-type transmission mechanism, and an antenna as a non-contact transmission mechanism. The external terminal as the contact type transmission mechanism is formed as a conductor pattern on the module substrate. Further, an antenna as a non-contact transmission mechanism of the IC module is embedded in a card base, and an IC module mounting hole is formed in the card base in a final step,
The antenna terminal of the module is connected to the antenna.
In the card having such a configuration, adjusting the capacitance of the resonance capacitor, such as managing the correspondence between the IC module and the antenna, complicates the manufacturing process and increases the manufacturing cost.

[0011]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and is used for setting a resonance frequency of an antenna circuit including a coil and a capacitor in a card manufacturing process. It is an object of the present invention to provide a non-contact IC card system and an external read / write device of a technology which does not require adjustment of the capacitor capacity, has a receiving sensitivity enough to obtain a sufficient communication distance, and can maintain a practical operation state.

[0012]

Means provided by the present invention for solving the above-mentioned problems are:
As shown in the figure, a non-contact IC card having a non-contact IC card for transmitting information and power in a non-contact manner and a non-contact IC having an external read / write device
A card IC card system, wherein the external read / write device comprises: (a) data transmission / reception means for transmitting / receiving information to / from a non-contact IC card at a predetermined frequency; and (b) varying a transmission frequency around a specified frequency. (C) a reception frequency seeking means for detecting the peak of the reception signal, and a reception frequency auto-tuning means for stopping the transmission frequency sweep when the reception signal becomes maximum. A non-contact IC card system comprising all of (c).

According to another aspect of the present invention, there is provided a non-contact IC card external read / write device capable of non-contact reading and writing of a non-contact IC card for transmitting information and power in a non-contact manner. Data transmission / reception means for transmitting / receiving information to / from a non-contact IC card at a frequency, (e) transmission frequency scanning means for varying and sweeping a transmission frequency around a specified frequency, and (f) reception for detecting a peak of a reception signal External reading and writing of a non-contact IC card, comprising: frequency seek means and a receiving frequency auto-tuning means for stopping the sweep of the transmission frequency when the received signal becomes maximum, and all of the above (d) to (f). Device. The external read / write device for a non-contact IC card according to claim 6 preferably has the same features as those of the external read / write devices that are elements of the non-contact IC card system according to claims 2 to 5.

According to the invention such as the non-contact IC card system according to the first aspect or the external reading / writing device for the non-contact IC card according to the sixth aspect, the tuning frequency of the non-contact IC card deviates from the design value. Even if the external read / write device sweeps the frequency, the frequency of the card can be searched for, locked to the frequency tuned to the card, and communication with the card can be performed. As a result, there is no need to precisely match the resonance frequency of the non-contact IC card, and the manufacture of the non-contact IC card becomes much easier than before. A particularly preferable example of the reception frequency seek means for detecting the peak of the reception signal shown in the above (c) or (f) is one in which the phase inversion of the impedance of the transmission / reception antenna of the external read / write device is made uniform so that the peak of the reception signal is obtained. Is detected.

According to a second aspect of the present invention, when one or more non-contact IC cards are present in a communication area, the external read / write device includes one or more non-contact IC cards in the communication area.
Communication that can detect that a card is present and that one or more tuning frequencies have been detected, transmit at one or more detected tuning frequencies, and communicate with one or more contactless IC cards in the communication area. It is characterized by having management means. The non-contact IC card system includes such an external read / write device.

According to the second aspect, even when a plurality of contactless IC cards having different tuning frequencies simultaneously enter the communication area of the system, the communication operation can be performed sequentially.

According to a third aspect of the present invention, the communication management means is further provided with a feature, and one or more detected tuning frequencies are time-divided and transmitted, and one or more tuning frequencies within the communication area are transmitted.
It is also preferable to sequentially communicate with the above-mentioned non-contact IC card.

It is preferable that the communication management means further has a feature, and stores that one or more non-contact IC cards are present and that one or more tuning frequencies are detected.

The communication management means may further provide a feature, transmit all detected tuning frequencies, and perform communication with all contactless IC cards in a communication area. Is also preferred.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The basic structure and basic principle of a non-contact transmission mechanism according to the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of an external read / write device of the contactless IC card system according to the present invention.

In FIG. 1, a data transmitting means 101 and a data receiving means 10 of a non-contact type external reading device 100 are shown.
A transmission / reception antenna 103, which is an electromagnetic coupler for supplying power to the non-contact transmission mechanism of the non-contact IC card 1 and transmitting / receiving information, is connected to 2.

On the other hand, as shown in FIG. 2, a non-contact transmission mechanism of the non-contact IC card 1 is an antenna which is directly electromagnetically coupled to the transmission / reception antenna 103 of the external reader 100 and is involved in power reception and information transmission / reception. This is a tuning circuit including a coil 4 and a resonance capacitor 5. A non-contact IC chip 3 is connected to a terminal of the antenna or the coil 4.
This non-contact transmission mechanism is enclosed in the card base 2.

Here, when transmitting power and information from the external read / write device 100 to the non-contact IC card 1, the non-contact IC whose tuning frequency is different from that of the external read / write device is used.
The procedure for detecting the card 1 will be described below.

A signal obtained by modulating the original signal of the oscillating means 105 provided in the external reading / writing apparatus 100 with data by the modulating means 106 is mixed with the output signal of the frequency varying means 104 by the transmission frequency scanning means 107, and the center frequency f0 To obtain a high frequency signal. A high-frequency magnetic field is induced in the transmitting / receiving antenna 103 by the high-frequency signal of the center frequency f0 transmitted to the data transmitting unit 101.
This high frequency signal is radiated into space as magnetic energy.

At this time, the non-contact I tuned to the frequency f0
When the C card 1 is located in the high-frequency magnetic field, a current flows through the antenna or the coil 4 of the non-contact IC card 1 by the high-frequency magnetic field generated by the transmission / reception antenna 103 of the external read / write device 100. The signal received by the antenna or the coil 4 is transmitted to the non-contact IC chip 3 connected to the terminal of the antenna or the coil 4. The non-contact IC chip 3 rectifies the received high-frequency signal so that the non-contact IC chip 3
The driving power of the chip 3 is obtained. In addition, the non-contact IC chip 3
The data is restored by a demodulation circuit (not shown) built in.

However, the maximum transmission efficiency between the transmitting / receiving antenna 103 of the external read / write device 100 and the antenna or coil 4 of the non-contact IC card 1 is determined by the degree of synchronization with the communication frequency. If the tuning frequency of the non-contact IC card 1 deviates from the frequency radiated from the transmission / reception antenna 103 of the external read / write device 100, sufficient power is not induced in the antenna or the coil 4 of the non-contact IC card 1.

Therefore, in a system using the non-contact IC card 1 whose tuning frequency varies, the signal of the optimum tuning frequency of the non-contact IC card 1 is read by the external read / write device 10.
It is effective means that 0 can be selected.

In order to solve the problem of tuning without adjusting the circuit constant of the tuning circuit of the non-contact IC card in the manufacturing process, an external read / write device 100 of the present invention is used.
In addition, a transmission frequency auto scan function and a reception frequency seek function are provided. Next, these functions will be described in more detail.

Oscillator 105 of external read / write device 100
Oscillates at the frequency fp set in the system. In a normal non-contact IC card system, data is superimposed on this frequency fp by the modulator 106, and is radiated as high-frequency energy from the transmitting / receiving antenna 103 to the space via the transmitting circuit 101. In the present invention, the center frequency transmitted between the modulating means 106 and the data transmitting means 101 is swept over the transmission frequency within a certain frequency range, for example, within the maximum frequency shift fs. That is, an automatic scan function controlled by the CPU 110 having the frequency variable means 104 and the transmission frequency scan means 107 for changing the transmission frequency between the highest frequency fp + fs and the lowest frequency fp-fs is provided. As a result, all the non-contact IC cards 1 whose tuning frequency is within the range of fp ± fs can individually receive the optimum tuning frequency.

On the other hand, the external read / write device 100 always
While sweeping the transmission frequency, it waits for a response from at least one non-contact IC card 1. At the time of the reception operation of the external read / write device 100, a response signal from the non-contact IC card 1 is detected by the transmission / reception antenna 103 of the external read / write device 100 and guided to the data reception circuit 102 connected to the antenna. The normal receiving means comprises a data receiving means 102 and a demodulating means 108, and the demodulated signal is stored in a CPU 110 or the like.
1 is temporarily stored. Alternatively, it is transmitted to a higher-level device (not shown). In the present invention, the data receiving means 102 is provided with a seek function comprising a tuning means 109 for detecting the strength of a received signal and a CPU 110.

The external read / write device 100 constantly detects the response signal level of the non-contact IC card 1 while sweeping the transmission frequency. At a certain frequency, the response signal from the contactless IC card 1 exceeds the minimum detection level, and when a peak is detected, a tuning detection signal is output from the tuning means 109 to the CPU 110. With this output signal, the CPU 110 stops scanning the transmission frequency and executes communication with the non-contact IC card 1. When the communication is executed, the non-contact IC card 1 communicating with the external read / write device 100 sends a response signal as a response signal.
A D code is transmitted. The contactless IC card 1 having the same tuning frequency is identified by the ID code. Non-contact IC cards entering the communicable area of the external read / write device 100 are sequentially processed according to the procedure described above.

Furthermore, as shown in FIG. 3, if a plurality of non-contact IC cards 1 are simultaneously in the communicable area of the external read / write device 100 and one or more tuning frequencies are detected, first, The CPU 110 processes that a plurality of tuning frequencies are detected, and stores all the detected peak frequencies in the memory 111. Next, the detected frequencies f1, f2,..., Fn are sequentially transmitted, for example, and all the detected tuning frequencies in the order of card 1, card 2,. The communication with all the non-contact IC cards in the area is completed. If there are a plurality of contactless IC cards having the same tuning frequency, the IDs are assigned to the plurality of contactless IC cards.
Identify by code. If desired, a plurality of tuning frequencies among the detected frequencies f1, f2,... Fn are transmitted at a time, as long as the external read / write device according to the present invention has the ability to execute processing. , Or all of them may be transmitted at one time.

[0034]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
This is an example of a "composite IC card system" in which a non-contact IC card system is configured by applying to a complex IC card which is one form of a non-contact IC card. In addition, the compound IC card is
Although it is a single IC card, it not only has the function of a non-contact IC card, but also has a function of providing an external terminal and making contact with the external terminal to communicate with an external reading / writing device. Refers to an IC card. And, as the IC chip of the composite IC card, a type in which the non-contact type and the contact type are combined into one, or a type in which the non-contact type and the contact type are separate in one IC card are both used. Although it is conceivable, any of them may be used in applying the present invention.

FIG. 4 is a schematic configuration diagram of a complex IC card system according to the present invention. The composite IC card system according to an example of the present invention includes an external read / write device 200 and a composite IC card 10. External read / write device 20
0 denotes an oscillator 201, a modulation circuit 202, and a frequency mixing circuit 2 for non-contact information transmission with the complex IC card 10.
03, a local oscillator 208, a transmission unit including a data transmission circuit 204, a data reception circuit 205, a demodulation circuit 206,
A receiving means comprising a frequency peak detecting circuit 107, a transmitting / receiving antenna 103, a CPU 110 for controlling an auto tuning and a seek function, and a memory 111 for storing a detected frequency, a card ID code, and the like are provided. A PLL oscillator was used as the local oscillator 208, but any other oscillator whose output frequency can be changed is applied to the present invention.

The composite IC card 10 includes a composite IC module 11, a second coupling coil 12, and a resonance capacitor 1.
3. Card substrate 1 enclosing antenna inlet 15 having antenna or coil 14 formed on the surface with a conductor pattern
Consists of seven.

FIG. 5 shows a composite IC card 1 used in the present invention.
0 is a schematic configuration diagram. The composite IC module 11 includes a patterned terminal electrode 21 serving as a contact-type transmission unit, a composite IC chip 22 having a built-in contact type interface and a non-contact type interface (not shown), and a periphery of the composite IC chip 22 or a module substrate 23. , A first coupling coil 24 of a non-contact type transmission portion formed by a conductive wire provided with an insulating film around the module, and a module substrate 23. The composite IC chip 22 is mounted on the surface of the module substrate 23 opposite to the surface on which the terminal electrodes 21 are formed. Composite IC
The chip 22 and the terminal electrodes 21 of the module substrate 23 are connected by through holes. The circuit is formed by thermally welding the composite IC chip 22 and the circuit pattern of the first coupling coil 24 using solder or a conductive adhesive. This connection can also be realized by wire bonding the circuit formation surface of the composite IC chip 22 and the module substrate 23.

Subsequently, the composite IC card 10 according to the present invention
The manufacturing process will be briefly described.

First, a plastic film having copper foil adhered to both sides is prepared. This is etched to form a resonance capacitor 12 having a copper foil on both sides as an electrode, a second coupling coil 13, an antenna or a coil 14,
The antenna inlet is manufactured by cutting it slightly smaller than the card size. Next, the card substrate 17 is formed by injection molding so as to sandwich the antenna inlet. A chamber for the fitting hole 16 of the IC module is provided in the molding die, and the fitting hole 16 of the composite IC module 10 is formed simultaneously with the production of the card substrate 17 by injection molding. Finally,
Fitting hole 16 of compound IC module 11 of card board 17
The composite IC card 10 is completed by bonding the composite IC module 11 to the substrate. FIG. 6 shows a schematic equivalent circuit of the composite IC card configured as described above.

Although vinyl chloride was used as the card base material, any other material such as PET, polycarbonate, synthetic paper, etc., which can obtain sufficient card characteristics can be applied to the present invention.

In the present invention, the card is manufactured by injection molding. However, any method that maintains card characteristics can be applied to the present invention, and for example, a laminate method may be used. The fitting hole 16 of the IC module is
Hollowing after card molding is also included in the present invention.

[0042]

As is apparent from the above description, in the non-contact IC card system according to the present invention, the external read / write device comprises an oscillator for generating a carrier frequency, a data modulator and a non-contact IC at a predetermined frequency. In addition to the data transmission circuit that transmits and receives information to and from the card, transmission frequency scanning means that varies and sweeps the transmission frequency around the frequency specified between the modulator and the data transmission circuit, the reception circuit, and the demodulation circuit The reception frequency seek means for detecting the peak of the reception signal and the reception frequency auto-tuning means for stopping the sweep of the transmission frequency when the reception signal reaches the maximum are CP.
It was configured to be realized by U processing.

By incorporating this auto-tuning function into an external read / write device, it is possible to control all the products manufactured without adjusting the tuning circuit constant of a card including an antenna or a coil and a resonance capacitor enclosed in the card, which has been conventionally performed. Cards can be used.

[0044] This also eliminates the need for tuning adjustment equipment and processes in the card manufacturing process, so that a large cost saving effect can be obtained as compared with the related art.

After all, according to the present invention, it is possible to solve the problems of the prior art, and it is not necessary to adjust the capacitance of the capacitor for setting the resonance frequency of the antenna circuit composed of the coil and the capacitor in the card manufacturing process, so that sufficient communication is possible. It is possible to provide a non-contact IC card system and an external read / write device of a technology having a receiving sensitivity to obtain a distance and maintaining a practical operation state.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an external read / write device of a contactless IC card system according to the present invention.

FIG. 2 is a schematic configuration diagram of a non-contact IC card according to the present invention.

FIG. 3 is an explanatory diagram of simultaneous processing of a plurality of sheets in the non-contact IC card system according to the present invention.

FIG. 4 is a schematic configuration diagram of a complex IC card system according to an embodiment of the present invention.

FIG. 5 is a schematic configuration diagram of a composite IC card according to an embodiment of the present invention.

FIG. 6 is an equivalent circuit diagram of a non-contact coupling circuit for explaining the principle of the non-contact transmission mechanism according to the embodiment of the present invention.

[Explanation of symbols]

 1 ··· Non-contact IC card 2 ··· Card base 3 ··· Non-contact IC chip 4, 12 ··· Antenna or coil 5, 13 ··· Resonant capacitor 6 ··· Inlet 7 ··· Capacity adjuster 10 ··· Compound IC card 11 ··· Compound IC module 14 ··· Second coupling coil 15 ··· Antenna inlet 16 ··· Fit hole 17 ··· Card board 18 Resin sealing 21 Terminal electrode 22 Composite IC chip 23 Module board 24 First coupling coil 100, 200 External read / write device 101 Data transmission means 102 Data receiving means 103 transmitting / receiving antenna 104 local oscillation means 105 oscillation means 106 modulation means 107 transmission frequency scanning means 108 demodulation means 109 Tuning means 110 CPU 111 Memory 201 Oscillator 202 Modulation circuit 203 Frequency mixing circuit 204 Data transmission circuit 205 Data reception circuit 206 Demodulation circuit 207 Frequency peak detection circuit 208 ..Local oscillators

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Susumu Emori 1-5-1, Taito, Taito-ku, Tokyo Letterpress Printing Co., Ltd. F-term (reference) 2C005 MA18 NA02 NA09 PA18 PA27 RA02 RA07 RA12 SA12 TA22 5B035 AA04 BB09 CA23 5B058 CA17 KA40 5J070 BC29

Claims (6)

[Claims] 1. Non-contact I for transmitting information and power in a non-contact manner
A non-contact IC card IC card system comprising a C card and an external read / write device, wherein the external read / write device comprises: (a) data transmission / reception means for transmitting / receiving information to / from a non-contact IC card at a predetermined frequency; ) Transmission frequency scanning means for variably sweeping the transmission frequency around a specified frequency, (c) reception frequency seeking means for detecting the peak of the reception signal, and stopping the transmission frequency sweep when the reception signal becomes maximum. A non-contact IC card system comprising: a receiving frequency auto-tuning means for performing the above; (a) to (c). 2. When one or more non-contact IC cards are present in the communication area of the external read / write device, one or more non-contact IC cards are present in the communication area and one or more tuning frequencies are detected. Can be detected,
The non-contact IC according to claim 1, further comprising: communication management means for transmitting at one or more detected tuning frequencies and communicating with one or more non-contact IC cards in a communication area.
Card system. 3. The communication management means performs time-division transmission of one or more detected tuning frequencies, and sequentially communicates with one or more non-contact IC cards in a communication area. The contactless IC card system according to claim 1. 4. The communication management means according to claim 1, wherein said communication management means includes at least one non-contact IC.
The non-contact IC card system according to any one of claims 1 to 3, wherein the presence of the card and the detection of one or more tuning frequencies are stored. 5. The communication management means according to claim 1, wherein said communication management means transmits all detected tuning frequencies to communicate with all contactless IC cards in a communication area. A non-contact IC card system according to the item (1). 6. A non-contact I for transmitting information and electric power in a non-contact manner.
An external read / write device for a non-contact IC card capable of reading and writing a C card in a non-contact manner, comprising: (d) data transmission / reception means for transmitting and receiving information to and from the non-contact IC card at a predetermined frequency; (F) reception frequency seek means for detecting the peak of the reception signal, and reception frequency auto-tuning means for stopping the transmission frequency sweep when the reception signal becomes maximum. An external read / write device for a non-contact IC card, comprising all of the above (d) to (f).