JP2007019692A - Ic card communication system and communication method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an IC card communication system in which a reader writer can speedily detect the presence of a contactless IC card in a magnetic field. <P>SOLUTION: The contactless IC card 40 is equipped with a control section 42 which performs internal control over the contactless IC card 40, a transmission section 41 which modulates data from the control section 42, and a beacon transmission section 43 which transmits a beacon signal at constant intervals under the control from the control section 42, and the reader writer 20 is equipped with a control section 22 which controls transmission and reception of data to and from a terminal and the inner side of the reader writer 20, a transmission section 24 which modulates data from the control section 22, a reception section 25 which demodulates a signal received from the contactless IC card 40 through an antenna 23, and a beacon signal detection section 27 which detects a beacon transmitted from the contactless IC card 40. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an IC card communication system comprising a non-contact IC card and a reader / writer device, and more particularly to a technique for reducing communication time required for the reader / writer to detect a non-contact IC card.

  A conventional IC card communication system includes a contactless IC card that stores personal information, a reader / writer device that communicates with the contactless IC card and an electromagnetic wave via an antenna, and a terminal such as a personal computer that controls the reader / writer device. Consists of

  An example of communication operation in such an IC card communication system will be described with reference to FIG.

  First, a case where a non-contact IC card exists in a magnetic field will be described.

  When the reader / writer device receives the execution command 1 from the terminal, the reader / writer device transmits the execution command 2 to the non-contact IC card. When the reader / writer device receives a response 3 to the execution command 2 from the non-contact IC card, the reader / writer device transmits a response 4 to the terminal. That is, when the reader / writer device receives a response 3 to the execution command 2 from the non-contact IC card, the reader / writer device recognizes that the non-contact IC card exists in the magnetic field.

  Next, a case where a non-contact IC card is not present in the magnetic field will be described.

  When receiving the execution command 5 from the terminal, the reader / writer device transmits the execution command 6 to the non-contact IC card. However, the reader / writer device receives no response to the execution command 6 from the non-contact IC card (no response). Subsequently, the reader / writer device retransmits the execution command 6 to the non-contact IC card. However, the reader / writer device receives no response to the execution command 6 from the non-contact IC card (no response). Further, the reader / writer device retransmits the execution command 6 to the non-contact IC card. However, the reader / writer device receives no response to the execution command 6 from the non-contact IC card (no response).

  In response to this, the reader / writer device notifies the terminal that the non-contact IC card does not exist in the magnetic field, and cancels the activated state. That is, the reader / writer device recognizes that the non-contact IC card does not exist in the magnetic field when the response to the execution command 6 cannot be received from the non-contact IC card three times in succession.

  As described above, in the conventional IC card communication system, when the communication with the non-contact IC card is not performed for a long time, that is, when the execution command from the reader / writer device to the non-contact IC card is not performed for a long time. There is a problem that the reader / writer recognizes that the non-contact IC card is not present in the magnetic field.

  In recent years, in view of the above problems, a technique for determining whether a non-contact IC card is in a state of entering a magnetic field based on a change in electrical characteristics of an antenna of a reader / writer device has been disclosed (for example, Patent Documents). 1).

  FIG. 4 is a block diagram showing the internal configuration of such a reader / writer device.

  As shown in FIG. 4, the reader / writer device 10 includes a control unit 12 that performs internal control and command transmission / reception with a terminal (not shown), a transmission unit 14 that modulates transmission data from the control unit 12, and A receiving unit 15 that demodulates data from a non-contact IC card (not shown), an antenna 13, a detection circuit 18 that detects the output of the transmission unit 14, and an output of the detection circuit 18 is compared with a reference value and detected. And a determination circuit 17 that transmits a signal to the control unit 12.

With such a configuration, it is possible to detect a change in the electrical characteristics of the antenna due to the presence of the non-contact IC card in the magnetic field, so that there is no need to retry the execution command as in the conventional case, and immediate response can be improved. It can be done.
JP 2004-110815 A

  However, in the above-described method for detecting a change in the electrical characteristics of the antenna by the reader / writer device, the electrical characteristics of the antenna change even in the presence of metal in the vicinity of the reader / writer, and the contactless IC card and the reader / writer device itself. If the variation of the impedance of the antenna is taken into consideration, a new problem arises that it is difficult to set the threshold value of the change amount.

  In view of the above problems, an object of the present invention is to provide an IC card communication system and a communication method capable of quickly and easily detecting a state in which a non-contact IC card has entered a communication area.

In order to achieve the above object, an invention according to claim 1 of the present invention is an IC card communication system comprising a non-contact IC card and a reader / writer device.
The non-contact IC card includes a beacon transmission unit that transmits a beacon signal having a desired frequency at a desired interval, and the reader / writer device includes a beacon signal detection unit that detects the beacon signal.

  According to such a configuration, the reader / writer device can quickly detect the presence or absence of a non-contact IC card in the vicinity by detecting the cycle of the beacon signal.

  According to a second aspect of the present invention, in the first aspect of the present invention, the beacon signal has the same frequency as a carrier wave that transmits a command.

  According to such a configuration, the configuration can be simplified.

  The reader / writer device according to claim 3 is a communication method of an IC card communication system that transmits an execution command after detecting the beacon signal.

  According to such a configuration, when the non-contact IC card is not in the magnetic field, it is not necessary to retransmit the execution command because it is unnecessary to transmit the execution command.

  As described above, according to the present invention, when a non-contact IC card enters the magnetic field range of the reader / writer, a beacon signal is transmitted, and when this is detected, the reader / writer sends a detection command to perform communication. Since the sequence is started, it is not necessary to retry the execution command, and communication can be performed quickly.

  Further, the beacon signal can be easily configured by using the same frequency as the carrier wave.

  Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 and 2.

  FIG. 1 is a block diagram of an IC card communication system according to the present invention.

  As shown in FIG. 1, the IC card communication system includes a terminal 30 such as a personal computer, a reader / writer device 20, and a non-contact IC card 40.

  Here, the non-contact IC card 40 according to the present invention includes a control unit 42 that controls the inside of the non-contact IC card 40, a transmission unit 41 that modulates data from the control unit 42, and a control from the control unit 42. Thus, a beacon transmission unit 43 that transmits beacon signals at regular intervals, a reception unit 45 that demodulates a signal received from the reader / writer device 20 via the antenna 47, and a power supply unit (not shown) that supplies the internal circuit And.

  In addition, the reader / writer device 20 according to the present invention includes a control unit 22 that transmits / receives data to / from a terminal and controls the reader / writer device 20, a transmission unit 24 that modulates data from the control unit 22, and a non-contact IC. A receiving unit 25 that demodulates a signal received from the card 40 via the antenna 23 and a beacon signal detecting unit 27 that detects a beacon transmitted from the non-contact IC card 40 are provided.

  Note that a power source (not shown) used for an internal circuit of the non-contact IC card 40 converts the magnetic field energy induced by the antenna 47 into a voltage, and further smoothes and supplies the voltage.

  Next, the communication operation of the IC card communication system of the present invention having the above configuration will be described with reference to the sequence diagram of FIG.

  First, when the non-contact IC card 40 enters the magnetic field generated by the reader / writer device 20, the internal circuit of the non-contact IC card 40 is activated, the control unit 42 controls the beacon transmission unit 43, and the beacon 50 is read by the reader. Transmit to the writer device 20.

  Next, on the reader / writer device 20 side, the beacon detection unit 27 determines whether or not it is a beacon signal from the non-contact IC card 40. If the beacon signal is from the non-contact IC card 40, the control unit 22 Notifies the terminal 30 that the beacon 52 has been detected.

  That is, the terminal 30 recognizes that the non-contact IC card 40 has entered the magnetic field of the reader / writer device 20.

  Then, the terminal 30 transmits an execution command 55 to the reader / writer device 20, and the reader / writer device 20 transmits an execution command 56 to the non-contact IC card 40.

  The contactless IC card 40 that has received the execution command 56 transmits a response 58 to the reader / writer device 20, and the reader / writer device 20 transmits a response 59 to the terminal 30.

  Through the above sequence, the non-contact IC card 40 and the reader / writer device 20 shift to the activated state.

  According to the IC card communication system and the communication method of the present invention described above, whether or not the non-contact IC card exists in the magnetic field generated from the reader / writer device can be determined by the beacon from the non-contact IC card. Therefore, the reader / writer device does not need to retransmit the execution command.

  Further, according to the present invention, since the presence of the non-contact IC card is not detected by a magnetic field change, the non-contact IC can be surely detected even if there is an object that changes the magnetic field such as metal in the vicinity of the reader / writer device. The presence or absence of a card can be detected.

  In the above description, the beacon transmission cycle from the non-contact IC card has been described as a constant interval, but the present invention is not limited to this, and any specific transmission pattern may be used.

  In addition, by using the same frequency as the carrier wave used for the execution command and response as the beacon frequency, it is not necessary to provide a new frequency generation means, so the configuration can be simplified and the cost can be reduced. Can do.

  The present invention can be applied to a system that is required to quickly detect that a non-contact IC card has entered a communication area.

Configuration of IC card communication system of the present invention The sequence diagram which shows the communication method of the IC card communication system of this invention Sequence diagram showing a communication method of a conventional IC card communication system Block diagram showing the internal configuration of a conventional reader / writer device

Explanation of symbols

  10, 20 Reader / writer device

Claims (3)

In an IC card communication system comprising a non-contact IC card and a reader / writer device,
The contactless IC card includes a beacon transmission unit that transmits a beacon signal of a desired frequency at a desired interval, and the reader / writer device includes a beacon signal detection unit that detects the beacon signal. IC card communication system. 2. The IC card communication system according to claim 1, wherein the beacon signal has the same frequency as a carrier wave for transmitting a command. The reader / writer device transmits a detection command after detecting the beacon signal.

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