JP2006243779A - Collation system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a collation system capable of transmitting a further large power from a collation terminal to an information carrier. <P>SOLUTION: The collation terminal transmits a command signal designating a specified information carrier and a subsequent carrier wave signal toward an information carrier group by use of a first frequency, and transmits a preceding feed wave and a subsequent feed wave to the information carrier group by use of a second frequency. The preceding feed wave is transmitted prior to the command signal, the transmission of the command signal is started after the end of the preceding feed wave, and the transmission of the subsequent feed wave is started after the end of the command signal. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a verification system such as an RFID (Radio Frequency Identity System) system.

  This type of collation system includes a collation terminal and an information carrier, transmits a collation signal from the collation terminal toward the information carrier, and the information carrier returns a response signal to the collation terminal in response to the collation signal. The verification signal includes a command signal followed by a carrier signal. The command signal designates a specific information carrier, and the designated information carrier returns a response signal obtained by modulating the carrier signal with the stored information to the collation terminal, and the collation terminal transmits the response signal of the specific information carrier based on the response signal. Stored information can be obtained.

Japanese Laid-Open Patent Publication No. 9-18381 discloses an RFID system. In this RFID system, a verification terminal called a reader and an information carrier called an identification tag are used. The reading device transmits a verification signal called an interrogation radio wave toward the identification tag. The identification tag is a non-contact type non-contact identification tag, which converts the inquiry radio wave into electric power and supplies it to the control circuit. The identification tag generates a clock signal from the interrogation radio wave, and the control circuit outputs identification information. The transmission circuit of the identification tag uses the interrogation radio wave as a carrier wave and multiplexes the identification information on the carrier wave, thereby transmitting a response signal called a response radio wave to the reading device.

  In addition, paragraph 0014 of the prior art also discloses that the interrogation radio waves transmitted from the reading device are two types of interrogation radio waves for the first frequency for power supply and interrogation radio waves for the second frequency for signal communication. ing. Two types of interrogation radio waves, a first frequency interrogation radio wave for power supply and a second radio frequency interrogation radio wave for signal communication, are the first frequency interrogation radio wave for power supply and the second frequency for signal communication. Therefore, it is considered effective to supply a larger power source power to the identification tag of the non-power source system.

Japanese Patent Application Laid-Open No. 9-18183, especially paragraph 0014

  However, in order to transmit a sufficient power source to a non-powered information carrier, it is not yet sufficient to use only two types of interrogation radio waves.

  The present invention proposes an improved collation system so that a larger power can be supplied to a non-powered information carrier.

  A collation system according to the present invention includes a non-power-source information carrier group and a collation terminal, wherein the collation terminal designates a specific information carrier toward the information carrier group, and a carrier signal following the command signal. A specific information carrier transmitted using a first frequency and a specific information carrier specified by a command signal returns a response signal to the verification terminal based on a carrier wave signal, wherein the verification terminal uses the second frequency The preceding feeding wave and the subsequent feeding wave are transmitted toward the information carrier group, the preceding feeding wave is transmitted prior to the command signal, and the command signal is transmitted after the end point of the preceding feeding wave. The transmission of the subsequent feeding wave is started after the end of the command signal.

  In the collation system according to the present invention, the collation terminal transmits a command signal designating a specific information carrier and a subsequent carrier signal using the first frequency, and uses the second frequency and the preceding feed wave and the subsequent feed. Since radio waves are transmitted, a larger power source can be transmitted to the information carrier. In addition, the preceding feed wave is transmitted prior to the command signal, the command signal is transmitted after the end of the preceding feed wave, and the subsequent feed wave is transmitted after the end of the command signal. Therefore, the frequency does not interfere with other communication devices around the frequency due to the difference between the preceding feeding wave and the subsequent feeding wave and the command signal.

  Hereinafter, some embodiments of the verification system according to the present invention will be described with reference to the drawings.

Embodiment 1 FIG.
FIG. 1 is a system configuration diagram showing Embodiment 1 of the verification system according to the present invention, FIG. 2 is a block diagram showing the configuration of the verification terminal in Embodiment 1, FIG. 3 is a timing chart showing the operation of the verification terminal, and FIG. FIG. 5 is a block diagram showing the configuration of the information carrier in Embodiment 1, and FIG. 5 is a timing chart showing the operation of the information terminal.

  Embodiment 1 of the verification system according to the present invention is an RFID system. The RFID system according to the first embodiment is applied to a logistics management system, a bank card system in finance, a boarding card system in transportation, an entrance / exit management system for buildings, and the like. As shown in FIG. 1, the RFID system according to the first embodiment includes a network 10, a verification terminal 20, and an information carrier group 30. The information carrier group 30 includes a plurality of information carriers 31, 32, ..., 3n.

  The network 10 is connected to the verification terminal 20 using the coaxial cable 11. The network 10 supplies the control signal CS and the DC voltage VB to the verification terminal 20 through the coaxial cable 11, and the verification terminal 20 supplies the read output OS to the network 10 through the coaxial cable 11.

  The control signal CS includes an activation signal SS for the verification terminal 20, a command control signal CC designating a specific information carrier, for example, the information carrier 31, and a power supply control signal VC. The activation signal SS is a signal for activating the verification terminal 20, and the command control signal CC generates a verification signal SQ at the verification terminal 20. The power supply control signal VC controls generation of a power supply wave VW from the verification terminal 20 to the information carrier group 30. The read output OS is obtained by demodulating the response signal SR from the designated information carrier 31 at the verification terminal 20.

  The verification signal SQ is generated using the local oscillation signal S0 having the first frequency f1. This verification signal SQ includes a command signal SC and a carrier signal CW. The command signal SC is a signal for designating a specific information carrier in the information carrier group 30, for example, the information carrier 31, and is generated by, for example, ASK modulating the local oscillation signal S0 according to the command control signal CC. The carrier signal CW is a continuous wave generated following the command signal SC, and the local oscillation signal S0 is transmitted as it is without being modulated.

  The response signal SR is generated by the ASK modulation of the carrier signal CW received from the verification terminal 20 by the designated information carrier, for example, the information carrier 31, based on the related information IR to which the information carrier 31 is attached. Since this response signal SR includes related information IR of an attached object of a designated information carrier, for example, the information carrier 31, by demodulating the response signal SR at the matching terminal 20, the matching terminal 20 Related information IR can be obtained. This attached target related information IR is supplied to the network 10 as a read output OS.

  The plurality of information carriers 31, 32,..., 3n are attached to corresponding articles, cards, and people, respectively, and store related information IR of the attachment target. The verification terminal 20 reads related information IR to be attached to the information carrier designated by the command signal SC, for example, the information carrier 31.

  In FIG. 2, the verification terminal 20 includes a control circuit 201, a verification signal transmission unit 202, a response signal reception unit 203, a local oscillator 204, a circulator 205, a power transmission unit 206, a first antenna 207, and a first antenna 207. And two antennas 208. The control circuit 201 is connected to the network 10 via the coaxial cable 11. The control circuit 201 receives a DC voltage VB and a control signal CS from the network 10. The DC voltage VB is supplied to each part of the verification terminal 20. The activation signal SS included in the control signal CS activates the verification terminal 20, the command control signal CC is supplied to the verification signal transmission unit 202 as an ASK modulation signal, and the power supply control signal VC is supplied to the power transmission unit 206. .

  The verification signal transmission unit 202 is connected to the control circuit 201, the local oscillator 204, and the circulator 205. A command control signal CC is supplied from the control circuit 201, and a local oscillation signal S0 having the first frequency f1 is supplied from the local oscillator 204. The verification signal transmission unit 202 generates a verification signal SQ including the command signal CS and the carrier signal CW. The command signal CS is obtained by ASK modulating the local oscillation signal S0 having the first frequency f1 with the command control signal CC. The carrier wave signal CW is transmitted as it is without modulating the local oscillation signal S0. The carrier signal CW is generated following the command signal CS, and the command signal CS and the carrier signal CW are supplied to the circulator 205. The circulator 205 supplies the verification signal SQ to the first antenna 27.

  For example, a frequency of 950 MHz is used as the first frequency f1. Therefore, the verification signal SQ is a signal using this first frequency, that is, a first frequency of 950 MHz. The command signal CS is an ASK modulated signal having the first frequency, and the carrier signal CW is a continuous wave having the first frequency.

  The response signal receiving unit 203 is connected between the control circuit 201 and the circulator 205, and receives the local oscillation signal S0 having the first frequency f1 from the local oscillator 204. The response signal SR is received by the first antenna 207 and supplied to the response signal reception unit 203 by the circulator 205. The response signal SR is obtained by subjecting the carrier wave signal CW to ASK modulation with a specified specific information carrier, for example, related information IR to be attached to the information carrier 31, and this response signal SR is a local oscillation signal S0 of the first frequency f1. , The related information IR to be attached to the information carrier 31 is obtained as a demodulated output. This demodulated output is supplied to the control circuit 201 and supplied to the network 10 via the coaxial cable 11 as a read output OS.

  The power transmission unit 206 is connected between the control circuit 201 and the second antenna 208. The power transmission unit 206 receives the supply wave control signal VC from the control circuit 201. The power transmission unit 206 incorporates a second local oscillator having the second frequency f2, and the second local oscillator generates a local oscillation signal having the second frequency f2. The power transmission unit 206 generates the feed wave VW having the second frequency f2 based on the feed wave control signal VC. This feed wave VW includes a preceding feed wave VW 1 and a subsequent feed wave VW 2, and this feed wave VW is transmitted from the second antenna 208. For example, a frequency of 2.4 GHz is used as the second frequency f2 of the feed wave VW.

  FIG. 3 is a timing chart showing the operation of the verification terminal 20. 3A shows a verification signal SQ transmitted from the verification terminal 20 to the information carrier group 30, and FIG. 3B shows a specific information carrier designated in the information carrier group 30, for example, information A response signal SR from the carrier 31 is shown, and FIG. 3C shows a feed wave VW transmitted from the verification terminal 20 toward the information carrier group 30.

  The horizontal axis of FIG. 3 is a time axis, and three continuous periods T1, T2, and T3 are shown. The start time of the period T1 is t1, the start time of the period T2 is t2, the start time of the period T3 is t3, and the end time of the period T3 is t4. The start time t2 of the period T2 coincides with the end time of the period T1, and the start time t3 of the period T3 coincides with the end time of the period T2.

  As shown in FIG. 3A, the command signal CS of the verification signal SQ starts to be transmitted from the start time t2 of the period T2, and the transmission ends at the start time t3 of the period T3. The carrier signal CW of the verification signal SQ starts to be transmitted from the start time t3 of the period T3 with the end of the command signal CS, and the transmission ends at the end time t4 of the period T3.

  The response signal SR is a response signal from the designated information carrier 31, for example, and is obtained by ASK modulation of the carrier signal CW. Therefore, as shown in FIG. 3B, the start time of the period T3 in the period T3 Reception is started from a time point delayed by a predetermined time tr from t3. The reception of the response signal SR ends at the end time t4 of the period T3.

  As shown in FIG. 3C, transmission of the preceding feeding wave VW1 of the feeding wave VW is started from the start time t1 of the period T1, and this preceding feeding wave VW1 is transmitted for a predetermined time tv1 from the start time t2 of the period T2. The transmission is terminated at a time point that precedes only. In other words, transmission of the command signal CS is started after the end point of the preceding feeding wave VW1. Both the preceding feed wave VW1 and the command signal CS are radiated from the verification terminal 20 at high power, and if they overlap, the frequency f2-f1 of the difference between them may interfere with other communication devices such as PHS mobile phones. However, due to the predetermined time tv1, the preceding feeding wave VW1 does not overlap with the command signal CS, and does not interfere.

  As shown in FIG. 3C, transmission of the subsequent feed wave VW2 of the feed wave VW is started from a time point delayed by a predetermined time tv2 from the start time point t3 of the period T3. In other words, after the transmission of the command signal CS is completed, the transmission of the subsequent feeding wave VW2 is started. This subsequent feeding wave VW2 is also high power. However, this subsequent feeding wave VW2 does not overlap with the command signal CS by this predetermined time tv2, and when the subsequent feeding wave VW2 and the command signal CS overlap, The difference frequency f2-f1 does not interfere with other communication apparatuses.

  The transmission of the subsequent feeding wave VW2 is finished at the end time t3 of the period T3. Since the predetermined time tv2 is slightly longer than the predetermined time tr, the subsequent feeding wave VW2 overlaps with the carrier wave signal CW and also overlaps with the response signal SR. However, although the subsequent feeding wave VW2 and the carrier wave signal CW are different in frequency, they are both continuous waves, so that there is no interference to other communication devices due to the difference frequency f2-f1, and the response signal SR is a carrier wave. Since it is attenuated compared to the signal CW, there is no problem that the frequency f2-f1 of the difference between them interferes with other communication devices.

  FIG. 4 shows the configuration of one information carrier, for example, the information carrier 31 in the first embodiment, but all the information carriers 31, 32,..., 3n are configured as shown in FIG. As shown in FIG. 4, each information carrier 31, 32,..., 3n includes a first antenna 301, a second antenna 302, a control switch 303, a verification signal receiving unit 304, a control circuit 305, And a feed wave receiving unit 306.

  The switch 303 is a changeover switch that switches between the switch a and the switch b. The switch a of the changeover switch 303 connects the first antenna 301 and the verification signal receiving unit 304. A switch b of the changeover switch 303 connects the first antenna 301 and a reference potential (ground). The output point A of the switch a is connected to the collation signal receiving unit 304, but the receiving unit 303 side of the output point A is impedance-matched with respect to the first frequency f1 of the collation signal SQ to form a non-reflection termination circuit. Yes.

  The verification signal receiving unit 304 demodulates the command signal CS of the response signal SQ, and the demodulated output of the command signal CS is supplied to the control circuit 305.

  The control circuit 305 includes a memory that stores related information to be attached and a power supply capacitor that operates the memory. When a specific part of the related information IR to be attached stored in the memory, for example, the head part thereof, and the demodulated output of the command signal CS are compared and they match, each information carrier is called by the verification signal SQ. Recognize that. The verification signal SQ is transmitted toward the information carrier group 30, but the information carrier, for example, the information carrier 31, in which the head portion of the stored related information matches the demodulated output of the received command signal CS is called. Recognize

  The power supply capacitor included in the control circuit 305 is charged by the feed wave receiving unit 306 and supplies an operating voltage to a memory that stores the related information IR of the attachment target. The information carrier that has recognized the call, for example, the information carrier 31 returns the related information IR to be attached as a response signal SR based on the carrier signal CW following the command signal CS. This response signal SR is a signal obtained by ASK modulating the carrier signal CW. Specifically, the related information IR to be attached stored in the memory is read from the memory, and the changeover switch 303 is switched accordingly. The carrier signal CW is terminated in a non-reflecting state when switched to the switch a, but when switched to the switch b, the reflected wave of the carrier signal CW is returned from the first antenna 301.

  FIG. 5 is a timing chart showing the operation of the information carrier. 5A shows the received verification signal SQ, FIG. 5B shows the response signal SR, FIG. 5C shows the received feed wave VW, and FIG. 5D shows the power supply capacitor. The charging voltage VC is shown.

  The horizontal axis in FIG. 5 is also a time axis, and shows the same three consecutive periods T1, T2, and T3 as in FIG. As in FIG. 3, the start time of the period T1 is t1, the start time of the period T2 is t2, the start time of the period T3 is t3, and the end time of the period T3 is t4. The start time t2 of the period T2 coincides with the end time of the period T1, and the start time t3 of the period T3 coincides with the end time of the period T2.

  The check signal SQ, the response signal SR, and the start point and end point of the feed wave VW shown in FIGS. 5A, 5B, and 5C are the signals shown in FIGS. 3A, 3B, and 3C, respectively. At the same time. The power capacitors included in the control circuits 305 of the information carriers 31, 32,..., 3n are charged by the feed wave VW and change as shown in FIG. In the first embodiment, the power supply capacitor is not charged by the verification signal SQ.

  As shown in FIG. 5D, the charging voltage VC of the power supply capacitor rises due to the preceding feeding wave VW1 in the period T1, and gradually decreases after the preceding feeding wave VW1 ends. The decrease in the charging voltage of the power supply capacitor continues in the period T2, and rises again with the start of transmission of the subsequent feeding wave VW2 in the period T3. By having a sufficient charging voltage at the start time t3 of the period T3, a sufficient charging voltage can be ensured particularly when the response signal SR is returned.

  The length of the period T1 can be set regardless of the length of the period T2. It is easy to make the length of the period T1 longer than the length of the period T2. By setting T1> T2, the charging voltage at the start time t3 of the period T3 can be further increased. A sufficient charging voltage VC can be ensured when the response signal is returned.

  In the first embodiment described above, the verification terminal 20 transmits the command signal SC for designating a specific information carrier and the subsequent carrier signal CW using the first frequency f1, and using the second frequency f2. Since the preceding feeding wave VW1 and the subsequent feeding wave VW2 are transmitted, a larger power source can be transmitted to the information carrier. In addition, the preceding feed wave VW1 is transmitted prior to the command signal SC, the command signal SC is transmitted after the end of the preceding feed wave VW1, and the subsequent feed wave VW2 is transmitted after the end of the command signal SC. Since transmission is started, the frequency of the difference between the preceding feed wave VW1 and the subsequent feed wave VW2 and the command signal SC does not disturb other communication devices in the vicinity.

  The verification system according to the present invention is applied to a physical distribution management system, a bank card system in finance, a boarding card system in transportation, an entrance / exit management system for buildings, and the like.

The system block diagram which shows Embodiment 1 of the collation system by this invention. FIG. 3 is a block diagram illustrating a configuration of a verification terminal according to Embodiment 1. 4 is a timing chart illustrating the operation of the verification terminal according to Embodiment 1. FIG. 2 is a block diagram showing a configuration of an information carrier in the first embodiment. 4 is a timing chart showing the operation of the information carrier in the first embodiment.

Explanation of symbols

10: network, 11: coaxial cable, 20: verification terminal, 201: control circuit,
202: collation signal transmission unit, 203: local oscillator, 204: circulator,
205: Response signal reception unit, 206: Feed wave transmission unit, 207: First antenna,
208: second antenna, 30: information carrier group, 31, 32, ..., 3n: information carrier,
301: First antenna 302: Second antenna 303: Changeover switch
304: collation signal receiving unit, 305: control circuit, 307: feeding wave receiving unit.

Claims (8)

A non-power-source information carrier group and a collation terminal, wherein the collation terminal transmits a command signal designating a specific information carrier toward the information carrier group and a subsequent carrier signal using a first frequency. The specific information carrier specified by the command signal is a verification system that returns a response signal to the verification terminal based on the carrier signal,
The verification terminal is configured to transmit a preceding feed wave and a subsequent feed wave toward the information carrier group using a second frequency;
The preceding feed wave is transmitted prior to the command signal, the command signal starts to be transmitted after the end of the preceding feed wave, and the subsequent feed wave starts to be transmitted after the end of the command signal. Matching system characterized by being made. 2. The verification system according to claim 1, wherein transmission of the command signal is started after a predetermined time from the end of the preceding feeding wave. 2. The verification system according to claim 1, wherein transmission of the subsequent feeding wave is started after a predetermined time from the end of the command signal. The verification system according to claim 1, wherein the subsequent feeding wave is transmitted in a period overlapping with the carrier wave signal. 5. The verification system according to claim 4, wherein the transmission of the subsequent feeding wave is terminated at the end of the carrier signal. The collation system according to claim 1, wherein the collation terminal includes a first antenna and a second antenna, the first antenna transmits the command signal and a carrier wave signal, receives the response signal, and The second antenna transmits the preceding feeding wave and the succeeding feeding wave. The verification system according to claim 1, wherein the second frequency is higher than the first frequency. The collation system according to claim 1, wherein the first frequency is 950 MHz and the second frequency is 2.4 GHz.

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