WO1999052223A1 - Dispositif d'identification sans contact d'un objet en mouvement - Google Patents

Dispositif d'identification sans contact d'un objet en mouvement Download PDF

Info

Publication number
WO1999052223A1
WO1999052223A1 PCT/JP1998/001573 JP9801573W WO9952223A1 WO 1999052223 A1 WO1999052223 A1 WO 1999052223A1 JP 9801573 W JP9801573 W JP 9801573W WO 9952223 A1 WO9952223 A1 WO 9952223A1
Authority
WO
WIPO (PCT)
Prior art keywords
frequency
receiving
coil
capacitor
response signal
Prior art date
Application number
PCT/JP1998/001573
Other languages
English (en)
Japanese (ja)
Inventor
Hirofumi Fujino
Hiroshi Ishida
Shunzi Watanabe
Original Assignee
Mitsubishi Denki Kabushiki Kaisha
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mitsubishi Denki Kabushiki Kaisha filed Critical Mitsubishi Denki Kabushiki Kaisha
Priority to PCT/JP1998/001573 priority Critical patent/WO1999052223A1/fr
Publication of WO1999052223A1 publication Critical patent/WO1999052223A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B5/00—Near-field transmission systems, e.g. inductive or capacitive transmission systems
    • H04B5/70—Near-field transmission systems, e.g. inductive or capacitive transmission systems specially adapted for specific purposes
    • H04B5/77—Near-field transmission systems, e.g. inductive or capacitive transmission systems specially adapted for specific purposes for interrogation
    • G—PHYSICS
    • G06—COMPUTING; CALCULATING OR COUNTING
    • G06K—GRAPHICAL DATA READING; PRESENTATION OF DATA; RECORD CARRIERS; HANDLING RECORD CARRIERS
    • G06K7/00—Methods or arrangements for sensing record carriers, e.g. for reading patterns
    • G06K7/0008—General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B5/00—Near-field transmission systems, e.g. inductive or capacitive transmission systems
    • H04B5/20—Near-field transmission systems, e.g. inductive or capacitive transmission systems characterised by the transmission technique; characterised by the transmission medium
    • H04B5/22—Capacitive coupling

Definitions

  • the present invention relates to a non-contact moving object identification device for products in a factory automation line for managing products and parts or in a transport system.
  • the non-contact mobile object identification device is composed of a transponder and an interrogator.
  • the signal is generated and transmitted by the transmitting circuit to the transponder after being modulated by the carrier having the first frequency f1.
  • the transponder is fixed to the mobile object to be identified.
  • the transponder demodulates the command from the interrogator and writes or reads the data to / from the built-in memory (rewriting the contents stored in the memory).
  • the response (response signal transmitted to the interrogator) is modulated by the carrier of the second frequency f2 and transmitted to the interrogator.
  • a capacitor 21 is connected to the induction coil 20 via a resistor 18 that stabilizes communication, a parallel resonance circuit that resonates at a second frequency f2, and a gain that decreases at the first frequency fl.
  • a low-pass filter 25 composed of a coil 24 and a capacitor 23, which has a function of suppressing the phase from changing near the frequency f2 without decreasing at the second frequency f2.
  • an amplifier 26 for amplifying the output voltage of the low-pass filter 25.
  • the resistance value of the resistor 18 that stabilizes communication depends on the long communication distance.
  • the resonance impedance changes due to the influence of the mutual inductance of the transponder antenna circuit, and the communication reliability decreases.
  • the communication distance was shortened if the selection was made based on the case where the communication distance was short.
  • the low-pass filter 25 reduces the gain at the first frequency il, does not decrease at the second frequency f2, and suppresses the phase change near the second frequency f2. And the second frequency f 2 ⁇ cutoff frequency fc.
  • the present invention has been made to solve the above problems, and has as its object to provide a non-contact mobile object identification device that improves communication reliability.
  • the non-contact mobile object identification device transmits a modulated command signal to the transponder using a carrier wave of a first frequency, and receives the transmitted response signal.
  • a non-contact moving object identification device including a transponder that modulates and transmits a carrier wave having a frequency of 2 and includes a receiving coil that receives the response signal by electromagnetic induction, A receiving capacitor connected in parallel to the coil, one end of which is grounded, and which resonates at the second frequency; A series coil having one end connected in series to the other end of the receiving capacitor, a series capacitor connected in parallel to the series coil and resonating at the first frequency, and a voltage at the other end of the series capacitor. And demodulation means for demodulating based on the following.
  • the non-contact mobile object identification device of the second aspect transmits a command signal modulated using a carrier wave of a first frequency to the transponder, receives the transmitted response signal, and demodulates the demodulated data. And an interrogator that generates the response signal, which is fixed to the mobile object to be identified, demodulates the transmitted command signal and writes or reads data in or from the internal memory, and generates the response signal of the second frequency.
  • a non-contact mobile object identification device comprising a transponder that modulates and transmits a carrier wave, wherein the interrogator includes a receiving coil that receives the response signal by electromagnetic induction, and a receiving coil that receives the response signal by electromagnetic induction.
  • a receiving capacitor that resonates at a first frequency via a resistor, and the resistor has a resistance value lower than the impedance of resonance between the receiving coil and the receiving capacitor based on the second frequency.
  • Resistance and A second resistor having a resistance value higher than the first resistance value, a switch means for selecting the first or second resistance, and detecting that the communication distance has reached a predetermined value. And a control means for switching the switch means based on a signal from the detection means.
  • FIG. 1 is a block diagram of a non-contact moving object identification device showing one embodiment of the present invention.
  • FIG. 2 is a block diagram of a non-contact moving object identification device showing another embodiment of the present invention.
  • FIG. 3 is a curve diagram showing the relationship between the primary current I 1 in FIG. 2 and the communication distance.
  • FIG. 4 is a characteristic curve diagram of voltage versus frequency of a resonance circuit of the non-contact moving object identification device of FIG.
  • FIG. 5 is a connection diagram showing a receiving unit of a conventional non-contact moving object identification device.
  • FIG. 6 is a curve diagram showing the gain and phase relative frequency characteristics of the low-pass filter of FIG.
  • FIG. 7 is a curve diagram showing gain and phase relative frequency characteristics of the low-pass filter of FIG. BEST MODE FOR CARRYING OUT THE INVENTION
  • FIG. 1 is a block diagram of a non-contact moving object identification device showing one embodiment of the present invention.
  • the non-contact mobile object identification device includes an interrogator 2 controlled by a higher-level control device (not shown) and a transponder 3, and a command is issued from the interrogator 2 to the transponder 3. It transmits signals and power, and always transmits unmodulated power waves without transmitting command signals.
  • the interrogator 2 includes a transmission unit, a reception unit, and an interface circuit (hereinafter, referred to as an I / F circuit) 10.
  • the transmission unit is transmitted from a higher-level control device via the I / F circuit 10.
  • the command signal When the command signal is modulated, it consists of a modulation circuit 11 and a transmitting antenna in which a capacitor 13 and a coil 15 are connected in series to the output of the modulation circuit 11.
  • a reception antenna (parallel resonance circuit) that is connected in parallel to a reception coil 20 that receives a response signal from the transponder 3 and that resonates at a second frequency f 2;
  • One end of the receiving capacitor 21 is grounded and the series capacitor connected in series to the other end of the receiving capacitor 21
  • the series coil 1 2 4 are connected in parallel, and the output voltage of the band-stop filter 125 and the output voltage of the band-stop filter 125 whose resonance frequency is the first frequency f 1 is amplified.
  • a demodulation circuit 28 as demodulation means for demodulating a response signal from the output of the amplifier 26. Since the resonance frequency f1 and the second frequency f2 of the carrier wave are considerably different, the phase in the vicinity of the second frequency f2 does not greatly change.
  • the transponder 3 is connected in parallel to a transmission / reception coil 30 for transmitting / receiving a transmission signal to / from the interrogator 2, and has an antenna circuit composed of a resonance capacitor 31 that resonates at a second frequency f2; Demodulation circuit 33 that demodulates the received signal or modulates the response signal, rectifier circuit 35 that rectifies the power (current) received by the antenna circuit and uses it as the power supply for the transponder, 3 and a control circuit 37 including memory for transmitting and receiving signals, analyzing the command signal 4 and creating a response signal.
  • the command signal is transmitted from the interrogator 2 to the transponder 3, the transponder 3 receives this command signal with the antenna circuit, the modulation / demodulation circuit 33 demodulates the command signal, and the control circuit 37 receives the command signal. 4 is analyzed and the data is written to the memory, a response signal is generated, and the modulation / demodulation circuit 33 modulates the response signal with the carrier of the second frequency f 2 and transmits the modulated signal to the reception antenna circuit of the interrogator 2.
  • the resonance circuit consisting of the receiving coil 20 and the receiving capacitor 21 resonates at the second frequency ⁇ 2, the band-stop filter 125 blocks the voltage at the first frequency f1, and the amplifier 26 The output voltage of the band reject filter 125 is amplified, and the demodulation circuit 28 demodulates the response signal.
  • FIG. 2 is a block diagram of a non-contact mobile object identification device showing one embodiment of the present invention.
  • the same reference numerals as those in the drawings denote the same or corresponding parts, and a description thereof will be omitted.
  • the non-contact moving object identification device includes a first resistor 2 having a lower resistance value than the resonance impedance Zc of the receiving coil 20 and the receiving capacitor 21 based on the second frequency f2. 0 1 and a second resistor 203 having a higher resistance value than the resistance value 201 of the first resistor.
  • the resistance value of the first resistor 201 is the resonance impedance Zc.
  • the resistance value of 1 Z 100 000 and the second resistor 203 is 1 Z 100 of the resonance impedance Zc.
  • Switch for selectively switching between the first resistor 201 and the second resistor 203 ⁇ Switch 205, coil 1 when the communication distance between interrogator 2 and transponder 3 has reached a predetermined value
  • a control unit 210 as control means for switching the switch 205 based on the signal of the current detector 207.
  • the primary current I 1 flowing through the coil 15 according to the distance between the interrogator 2 and the transponder 3 has the characteristics shown in Fig. 3, and the current value I s corresponding to the communication distance S is determined in advance. If the point of the communication distance S, that is, the detection current Ir of the detector 207 is Ir> Is, the first resistor 201 having a low resistance value is selected, and Ir ⁇ In the case of Is, the control section 210 is controlled to operate the switch 205 so that the second resistor 203 having a high resistance value is selected.
  • the operation of the non-contact moving object identification device configured as described above will be described with reference to FIG. 2 and FIG.
  • the current value Ir detected by the current detector 207 becomes Ir> Is, and the switch 2 is switched based on the command of the control unit 201.
  • the control unit 201 0 5 f Select the first resistor 2 0 1 with a low resistance value, and the parallel resonance circuit has a frequency vs. voltage curve with a low resistance value as shown in Fig. 4, where the Q of the parallel resonance circuit increases and the reception sensitivity of the antenna Increases.
  • the current value Ir detected by the current detector 207 becomes Ir ⁇ Is, and based on the command of the control unit 201, The switch 205 selects the second resistor 203 having a high resistance value, and the parallel resonance circuit has a high frequency vs. voltage curve shown in Fig. 4 with a high resistance value. Is suppressed.
  • the modulated command signal is transmitted to the transponder using the carrier of the first frequency, the transmitted response signal is received, and demodulated data is generated. While being fixed to the interrogator and the mobile unit to be identified, the transmitted command signal is demodulated and data is written or read from the built-in memory, and the generated response signal is modulated by the carrier wave of the second frequency.
  • a non-contact mobile object identification device including a transponder for transmitting a response signal, the interrogator having a receiving coil for receiving a response signal by electromagnetic induction, being connected in parallel to the receiving coil, and having one end grounded.
  • a receiving capacitor that resonates at a second frequency
  • a series coil having one end connected in series to the other end of the receiving capacitor, and a resonating capacitor that is connected in parallel to the series coil and has a first frequency.
  • the demodulation means for demodulating based on the voltage at the other end of the series capacitor, the second frequency forming the main frequency component of the response signal can be faithfully demodulated, and the voltage of the first frequency component Can be sufficiently reduced, so that there is an effect that communication reliability can be improved.
  • a command signal is transmitted to the transponder, the command signal being modulated using the carrier wave of the first frequency, the response signal transmitted is received, and a demodulated data is generated.
  • the generated response signal is modulated and transmitted by the carrier wave of the second frequency
  • a non-contact mobile object identification device including a transponder, wherein the interrogator transmits a response signal to the interrogator.
  • the receiving capacitor and the resistor that resonate at the frequency of 1 are the first resistor having a lower resistance value than the impedance of the resonance between the receiving coil and the receiving capacitor based on the second frequency, and the resistance is higher than the first resistance value.
  • the non-contact mobile object identification device is suitable for being used for non-contact communication by an interrogator and a transponder.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Artificial Intelligence (AREA)
  • Computer Vision & Pattern Recognition (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Near-Field Transmission Systems (AREA)

Abstract

L'invention concerne un interrogateur (2) qui comporte une bobine de réception (20) recevant un signal de réponse par induction électromagnétique, un condensateur de réception (21), connecté en parallèle à la bobine (20) et mis à la terre à l'un des bouts pour résonner avec ladite bobine (20) à une deuxième fréquence, une bobine (124) connectée en série avec l'autre bout du condensateur (21), un condensateur (123) qui est connecté en série avec le condensateur (21) et en parallèle avec la bobine (124) pour résonner avec la bobine (124) à une première fréquence, ainsi qu'un système de démodulation (28) qui démodule les signaux de réponse provenant d'un répondeur (3) sur la base de la tension à l'autre bout du condensateur (123).
PCT/JP1998/001573 1998-04-06 1998-04-06 Dispositif d'identification sans contact d'un objet en mouvement WO1999052223A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/JP1998/001573 WO1999052223A1 (fr) 1998-04-06 1998-04-06 Dispositif d'identification sans contact d'un objet en mouvement

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP1998/001573 WO1999052223A1 (fr) 1998-04-06 1998-04-06 Dispositif d'identification sans contact d'un objet en mouvement

Publications (1)

Publication Number Publication Date
WO1999052223A1 true WO1999052223A1 (fr) 1999-10-14

Family

ID=14207982

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP1998/001573 WO1999052223A1 (fr) 1998-04-06 1998-04-06 Dispositif d'identification sans contact d'un objet en mouvement

Country Status (1)

Country Link
WO (1) WO1999052223A1 (fr)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5083905U (fr) * 1973-12-04 1975-07-18
JPS63121773A (ja) * 1986-11-11 1988-05-25 Sharp Corp 移動体識別装置
JPH0933645A (ja) * 1995-07-21 1997-02-07 Oki Electric Ind Co Ltd トランスポンダの電源回路

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5083905U (fr) * 1973-12-04 1975-07-18
JPS63121773A (ja) * 1986-11-11 1988-05-25 Sharp Corp 移動体識別装置
JPH0933645A (ja) * 1995-07-21 1997-02-07 Oki Electric Ind Co Ltd トランスポンダの電源回路

Similar Documents

Publication Publication Date Title
US7164344B2 (en) Non-contact IC card reading/writing apparatus
JP4380239B2 (ja) 非接触ｉｃカード読取／書込装置
US5426667A (en) System for the contactless exchange of data, and responder for use in such a system
US6650226B1 (en) Detection, by an electromagnetic transponder reader, of the distance separating it from a transponder
JPH03113387A (ja) 移動体識別装置の応答器
US9767328B2 (en) Autonomous tuning method to improve radio frequency performance
JP3829577B2 (ja) 電磁トランスポンダシステムの全二重伝送方法
JP4336379B2 (ja) Ｒｆｉｄキャリアセンス方法及び，これを用いるｒｆｉｄシステム
WO1999052223A1 (fr) Dispositif d'identification sans contact d'un objet en mouvement
JP3800634B2 (ja) 非接触識別システム
JP4631571B2 (ja) Ａｓｋ復調器、無線通信装置、並びに反射波通信システム
JP2004206245A (ja) 非接触ｉｃカード読取／書込装置
JP3449621B2 (ja) 非接触ｉｃカードシステムのリーダ／ライタ装置
JP4605076B2 (ja) Ｒｆデバイスおよびｒｆデータ伝送方法
JP4117145B2 (ja) データ検出システムおよびデータ検出装置
JP4666738B2 (ja) 非接触ｉｃカード用リーダ／ライタ装置
JP2561051B2 (ja) 非接触式応答ユニット
JP3194715B2 (ja) 非接触ｉｃカードシステムのリーダ／ライタ装置
JP2000151457A (ja) 非接触移動体識別装置の共振周波数調整方法
JP3135838B2 (ja) 非接触データ送受信方法およびその装置
GB2331611A (en) Recovering data from a contactless data carrier
JPH10224277A (ja) リーダ・ライタ用アンテナ回路
JP3700927B2 (ja) 非接触移動体識別装置
JPS62213429A (ja) 電磁結合通信装置
JP2005328433A (ja) 無線式データキャリアシステム

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): DE JP US

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

NENP Non-entry into the national phase

Ref country code: JP

Ref document number: 2000542863

Format of ref document f/p: F