JP2001155121A - Non-contact ic card reader-writer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-contact IC card device which does not have to emit an undesired radio wave nor impose any burden on a user in order to eliminate the problems on the occurrence of unneeded power consumption in the case of continuously outputting a signal for card recognition all the time or the damage of a non-contact advantage in the case a user has to recognize a card approach by performing a special operation as a means recognizing the card approach because there is nothing coming into contact with the card in a non-contact type IC card. SOLUTION: A permanent magnet is incorporated in the antenna of a normal reader-writer, and when an IC card is brought close to a DC electric field generated by the permanent magnet, an induced current is generated in the card and the coil of the reader/writer on the basis of the low of electromagnetic induction, and the approach of the card is recognized by detecting the induced current.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a read / write device used for an electromagnetic induction type non-contact IC card system.

[0002]

2. Description of the Related Art An IC card using an IC memory is superior in the amount of information that can be stored and the security level as compared with a conventional magnetic card, and is used as a key for accessing a membership card, a network or a personal computer. It is used in various fields such as cards. In recent years, IC card systems that can read and write data in a non-contact manner have become widespread. In particular, in an electromagnetic induction type system using an AC magnetic field, power required for card operation is read and written by a reader / writer (reader / writer, R / W), and a system that does not have a battery mounted on the card can be configured. Currently, work on international standardization (ISO14443) is underway.
In the spring of 1997, the service as an IC telephone card was started. With the widespread use of electromagnetic induction type non-contact IC card systems, it has been considered that these non-contact IC cards are used as membership cards, and may be used as keys for logging in to a network from a personal computer. Can be Also, a PC card type R / W incorporated in a notebook personal computer for using a non-contact IC card at home has been considered (Japanese Patent Application No. 10-20 / 1990).
8714).

[0003] Non-contact IC cards operate literally without contacting the R / W, so they are convenient for users. However, when viewed from the R / W, it is always necessary to check the presence of the card. It is necessary for the card owner to perform some operation to operate the R / W after the signal for recognizing the ID is continuously output or the card is brought close to the vicinity of the R / W. However, the power consumption of the R / W increases in order to continuously transmit the signal, and there is a problem in incorporating the signal into a notebook personal computer, a portable terminal, or the like. Further, in the case where the card owner performs some operation, the convenience of the card operating in a non-contact manner is impaired. As described above, the R / W is required to have a mechanism for detecting a non-contact IC card with low power consumption and without any trouble of the user.

[0004]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an electromagnetic induction type R / W for an IC card which operates in a non-contact manner with the R / W which has been a conventional problem as described above. Unnecessary power consumption is reduced, and non-contact I
A means for detecting the approach or presence of the C card, whereby the R / W can be automatically set to the operation start state by detecting the IC card.
It is to provide.

[0005]

According to the present invention, in order to achieve the above object, an electromagnetic induction type non-contact IC card and a non-contact IC card system composed of the R / W of the same are used in the non-contact IC card. To start communication between the R / W, at the start of operation, the user inserts this IC card into the R / W.
Paying attention to performing an operation of approaching W, a method of detecting the proximity of the IC card and setting the R / W to an operation state is adopted.
For this reason, in a non-contact IC card system having a basic configuration including an antenna coil for performing communication between the IC card and the R / W, a transmitting / receiving circuit for communication, and a control circuit for controlling these circuits. A permanent magnet for detecting the approach of an IC card is incorporated in a conventional R / W antenna.

In the above configuration, in the present invention,
At the time of non-operation in the non-communication state, transmission of the carrier for communication is stopped, and the R / W enters the communication state by detecting that the above-mentioned IC card approaches, and transmission of the carrier is started. Also, when the system is in an operating state, a signal for confirming an IC card as a communication partner is transmitted from the R / W side at a predetermined time interval, and when there is no response thereto, a communication carrier and a signal are transmitted. Transmission is stopped.

[0007]

The operation of bringing the IC card close to the DC magnetic flux that does not change with time created by the permanent magnet causes the antenna coil of the IC card to cross this DC magnetic flux. An induced current is generated in the side antenna coil. Further, the induced current generates a magnetic flux in a direction to cancel the DC magnetic field according to Lenz's law, and the R / W side detects the magnetic flux from the IC card side so that the R / W detects the presence of the card. Things.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A mechanism for detecting an electromagnetic induction type non-contact IC card mounted on an R / W according to the present invention is shown in FIG.
This will be described with reference to FIG. In the figure, 101 is an R / W antenna coil, 102 is a permanent magnet, and 103 is a non-contact IC card antenna coil. By incorporating the permanent magnet 102 inside the R / W antenna coil 101, the R / W
A magnetic flux B1 that generates a static DC magnetic field that does not change with time is formed in the antenna coil of FIG. Here, when the non-contact IC card is brought close to the R / W (FIG. A),
When the antenna coil 103 of the C card crosses the DC magnetic flux B1 generated by the permanent magnet 102, an induced current I1 is generated in the antenna coil inside the card (FIG. B). A magnetic flux B2 in a direction to cancel the magnetic flux B1 generated by the permanent magnet 102 is generated (FIG. C). Since the magnetic flux B2 generated by the antenna coil 103 of the non-contact IC card passes through the R / W antenna coil 101, the time-varying magnetic flux B2 crosses the R / W antenna coil 101, and the R / W The induced current I2 flows through the antenna coil 101 (D diagram).
Therefore, if the R / W detects the induced current I2 flowing through the R / W antenna coil 101, it is possible to detect that an unrecognized non-contact IC card has been inserted into the communication area with the R / W. Becomes possible.

FIG. 2 is a functional block diagram of an R / W for an electromagnetic induction type non-contact IC card according to an embodiment of the present invention. In the figure, 201 is the R / W main body, 202 is a terminal such as a personal computer, 203 is a connection cable,
211 is an R / W antenna coil, 212 is a permanent magnet,
213 is an induced current detection circuit, 214 is a transmission / reception circuit, 21
5 is a control circuit, 216 is an interface circuit with a terminal,
217 is a power supply circuit. In the present embodiment, the R / W is electrically connected to a terminal such as a personal computer by a connection cable 203, and management of information to be written to the card and information to be read from the card is basically performed by the terminal 202. However, even if the card detection mechanism of the present invention is incorporated in a PC card type R / W, which is incorporated in a terminal with a PCMCIA interface and operates as shown in Japanese Patent Application No. 10-208714, no problem occurs. Needless to say. Also, in the case of PCMCIA type,
If the connection of / W is performed by a cable which can supply power such as USB, it is needless to say that a power supply circuit is not required for R / W.

FIG. 3 shows an R / W and a non-contact IC according to the present invention.
An example from the start of communication with the card to the end of R / W operation will be described. In the figure, 4 is a non-contact IC card, 18 is R / W
41 is an antenna coil of the non-contact IC card (the same as the antenna coil 103 in FIG. 1), and 42 is a circuit section of the non-contact IC card. In the R / W body 201 according to the present invention, the non-contact IC card 4
When the communication is not performed, there is a "waiting" state in which only the DC magnetic field (magnetic flux) B1 that does not change over time due to the permanent magnet exists (FIG. A). When the non-contact IC card 4 is approached, the detection circuit 213 of the R / W main unit 201 detects the non-contact IC card 4 and, based on the principle shown in FIG.
The transmission of the carrier C1 for communication and power supply with the card 4 is started (FIG. B). After carrier transmission, R / W main unit 20
1 transmits a signal for recognizing the non-contact IC card 4 or a signal S1 for communicating with the non-contact IC card 4, and the non-contact IC card 4 transmits a response R1 to the signal S1 to execute communication. (Fig. C). Further, in the R / W main unit 201 of the present invention, in order to continuously confirm that the non-contact IC card 4 exists in the communication area,
A signal for reading information from a predetermined memory area of the card and a signal S2 for detecting a non-contact IC card 4 'newly inserted in the communication area are transmitted to the non-contact IC card 4
In addition to reading / writing data from / to the card, transmission is continued at a predetermined time interval, and by receiving a response R2 from the card, the existence of the non-contact IC card 4 and the addition of a new non-contact IC card 4 'are confirmed. (D). Therefore, even when another non-contact IC card 4 ′ is inserted into the communication area while one non-contact IC card is being recognized, the non-contact IC card 4 ′ is inserted at intervals determined by the R / W main unit 201. The response signal R2 'from the added non-contact IC card 4' to the transmitted signal S2 for detecting the card can recognize the non-contact IC card. Non-contact I
Even when the C card 4 is separated from the communication area (FIG. E),
The R / W main unit 201 continues to transmit the signal S2 for card recognition and additional confirmation, but since there is no response from the non-contact IC card, the R / W can recognize that the card is gone, and Is stopped, and the state shifts to the "waiting" state similar to that shown in FIG. Thus, the R /
In W, the R / W main unit 201 is operating only when the non-contact IC card is present, and in other time zones, only the detection circuit is operating and is in a “waiting” state. Further, even during the communication between the R / W main unit 201 and the non-contact IC card 4 after the non-contact IC card 4 is inserted into the communication area, the magnetic flux B which does not change over time due to the permanent magnet.
1, the communication between the R / W main body 201 and the non-contact IC card 4 uses an AC magnetic field, so that the magnetic flux B1 does not affect the communication.

[0011]

As described above, according to the present invention, by incorporating a permanent magnet and a simple detection circuit into a conventional non-contact IC card R / W, the R can be obtained only by the operation of bringing the non-contact IC card close to the R / W. / W starts operation, and a non-contact IC card reader / writer that can suppress unnecessary power consumption when not in use has been realized.

[Brief description of the drawings]

FIG. 1 is a principle diagram of a method for detecting an R / W non-contact IC card according to the present invention.

FIG. 2 is a functional block diagram of an R / W according to the present invention.

FIG. 3 is an example of R / W operation according to the present invention.

[Explanation of symbols]

1: R / W, body 2: terminal 3: connection cable 4: non-contact I
C card 11, 101: R / W antenna coil, 102, 212: permanent magnet 18: R /
W circuit unit 213: detection circuit 214: transmission / reception circuit 215: control circuit 216: interface circuit with terminal 217: power supply circuit 41, 103: antenna coil of non-contact IC card, 42: circuit unit of non-contact IC card B1: Magnetic flux that does not change over time due to the permanent magnet B2: Magnetic flux generated by the non-contact IC card in a direction to cancel the magnetic flux generated by the R / W permanent magnet C1: Carrier transmitted by R / W, I1: Guided to the antenna coil of the card I2: Current induced in the R / W antenna coil, S1: Signal transmitted from R / W to card S2: Transmitted from R / W to card to recognize presence of card and addition of card R1: Response signal of card to S1 R2, R2 ': Response signal of card to S2

 ────────────────────────────────────────────────── ─── Continuing from the front page (72) Inventor Takashi Nishitani 2-3-1 Otemachi, Chiyoda-ku, Tokyo F-term in Nippon Telegraph and Telephone Corporation (reference) 5B058 CA15 CA22

Claims (3)

[Claims] An AC magnetic field is used as a communication medium to read and write data from and to an electromagnetic induction type non-contact IC card having a communication antenna coil, a storage element, a transmission / reception circuit, and a circuit for controlling these elements. A non-contact IC card reading and writing device, wherein the non-contact IC card reading and writing device includes a communication antenna coil;
At least a transmission / reception circuit and a circuit for controlling them, a permanent magnet is provided inside the antenna coil for communication, and a magnetic flux generated by the interaction between the magnetic flux by the permanent magnet and the antenna coil of the non-contact IC card A circuit for detecting a current induced in an antenna coil of the non-contact IC card reader / writer. 2. The non-contact IC card reading and writing device according to claim 1, wherein the carrier used for communication is stopped when the communication with the non-contact IC card is not performed. Wherein the detection circuit detects a current induced in an antenna coil of the read / write device by a time-varying magnetic flux generated by an interaction between the non-contact IC card and the permanent magnet, thereby communicating with the non-contact IC card. A non-contact IC card reading / writing device, which starts operation. 3. The non-contact IC card read / write device according to claim 1, wherein said non-contact IC card is in a communication state.
To the C card, a signal for reading into a specific memory area at a time interval set at intervals or recognizing an unrecognized non-contact IC card is transmitted. A non-contact IC card reader / writer which stops transmission of a communication carrier and a signal when there is no response.