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公开(公告)号：JP2001086030A
公开(公告)日：2001-03-30
申请号：JP2000218501
申请日：2000-07-19
Applicant: ST MICROELECTRONICS SA
Inventor： WUIDART LUC , ENGUENT JEAN-PIERRE
Abstract: PROBLEM TO BE SOLVED: To use a transponder and/or a terminal exclusively in a comparatively remote area by setting the characteristics of component elements of an oscillation circuit of the transponder to quickly attenuate the coupling coefficient between the oscillation circuits of both terminal and transponder when the distance set between the transponder and the terminal is smaller than a prescribed value. SOLUTION: When the distance between a transponder 10 and a terminal 1 is decreased, the coupling coefficient between the oscillation circuit of the transponder 10 and the terminal 1 is reduced quickly. The best measure of this problem shows that the optimum coupling point must be approximately equal to the center of a desirable distance operation area. When the distance between the transponder 10 and the terminal 1 deviates from the distance to the operation area, the coupling coefficient is quickly reduced and no power is supplied to the transponder 10 thereafter. The largest operation point is selected so that the voltage between the input terminals 11 and 12 of the transponder 10 lies in the interval between the voltage for which the least operating voltage of the transponder 10 corresponds to an inflection point and the voltage of the parallel oscillation circuit when the optimum coupling is secured between both oscillation circuits.
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公开(公告)号：JP2000332648A
公开(公告)日：2000-11-30
申请号：JP2000106525
申请日：2000-04-07
Applicant: ST MICROELECTRONICS SA
Inventor： WUIDART LUC , BARDOUILLET MICHEL , ENGUENT JEAN-PIERRE
Abstract: PROBLEM TO BE SOLVED: To reduce heating of a transponder when an operation power to a proximate transponder from a terminal is supplied by a radio by providing a means for detuning an oscillation circuit from a specific transmission frequency when the transponder approaches the terminal. SOLUTION: A terminal 1' is between an output terminal 2p of an amplifier, that is, an antenna coupler 3, and a terminal 2m in a reference potential (generally a ground), and includes an oscillation circuit consisting of a capacity parts 24, a resistor R1 and a serial impedance, that is, an antenna L1. Then, when the oscillation circuit of the terminal 1' and/or the oscillation circuit of a transponder are in a very close coupling relationship, in order to detune these, a phase of a current of the antenna L1 is adjusted to a reference signal REF. This adjustment is executed by changing a capacitance C1 of the oscillation circuit of the terminal 1' and maintaining the antenna current to a constant phase relationship with the reference signal.
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公开(公告)号：JPH11239016A
公开(公告)日：1999-08-31
申请号：JP34363398
申请日：1998-11-18
Applicant: ST MICROELECTRONICS SA
Inventor： ENGUENT JEAN-PIERRE
IPC: H01Q1/38 , G06K7/08 , G06K19/077 , H01Q7/00
Abstract: PROBLEM TO BE SOLVED: To obtain a coil which emits a low electric field by forming a conductive screen substantially in the same shape as a winding and forming an open loop circuit having a shield zone. SOLUTION: The coil 30 has a metal screen 35, coupled fixedly with a plate 33, on its reverse surface 30-2. The screen 35 is in the same shape as the winding 31 and its position on the reverse surface 30-2 is aligned with the position of the winding 31 on the front 30-1. The screen 35 is shaped in a frame having external dimensions L1 and I1 and internal dimensions L2 and I2 . Further, the screen 35 has the shield zone 36 and therefore forms the open loop conductive circuit including two ends 37 and 38 which never meet each other. The screen 35 never disturbs an effective magnetic field B which is directed along the axis and makes ineffective a parasitic electric field radiated by the winding 31. Consequently, a main feature which can be obtained is the shield zone and in the absence of this, the screen 35 forms the open loop circuit to short-circuit the magnetic field B.
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4.发明专利
公开(公告)号：JP2001086044A
公开(公告)日：2001-03-30
申请号：JP2000218500
申请日：2000-07-19
Applicant: ST MICROELECTRONICS SA
Inventor： WUIDART LUC , ENGUENT JEAN-PIERRE
Abstract: PROBLEM TO BE SOLVED: To permit operation only in an extreme proximity to prevent the surreptitious use due to interception by allowing a resonance circuit to have a specific characteristic that an electromagnetic coupling coefficient is suddenly reduced when the distance exceeds a prescribed value between a write/read terminal and an electromagnetic transponder. SOLUTION: The voltage that is induced by a transponder 10 is maximized with an optimum coupling coefficient set between a serial resonance circuit including a resistor R1, an inductance L1 and a capacitor C1 of a terminal 1 and a parallel oscillation circuit including an inductance L2 and a capacitor C2 of the transponder 10 and then reduced sharply on both sides of the transponder 10. Then the optimum coupling coefficient is expressed by a square root of R1L2/R2L1 with equivalent resistor R2 of the transponder 10, and each parts value of every oscillation circuit is set to secure the maximum voltage with a prescribed distance. In other words, the capacitor C2 that can obtain a prescribed frequency with a distance of 1 cm is reduced as much as possible and then the value of inductances L2 and L1 and capacitor C1 are successively set.
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公开(公告)号：JP2001007730A
公开(公告)日：2001-01-12
申请号：JP2000103473
申请日：2000-04-05
Applicant: ST MICROELECTRONICS SA
Inventor： WUIDART LUC , BARDOUILLET MICHEL , ENGUENT JEAN-PIERRE
IPC: G06K17/00 , G01S13/75 , G01S13/76 , G01S13/79 , G06K7/00 , G06K19/07 , H02J17/00 , H04B1/59 , H04L27/02
Abstract: PROBLEM TO BE SOLVED: To realize distance detection between a transponder and a terminal, which is executed on a terminal side and which does not require transmission from the transponder for the evaluation of the distance, by measuring a variable decided by a load formed on the oscillation circuit of the terminal through the means of the transponder. SOLUTION: A terminal 1' is located between the output terminal 2p of an amplifier, namely, an antenna coupler 3 and a prescribed terminal 2m in a reference potential, and it comprises an oscillation circuit formed of a capacitive part 24 and an inductance connected to a resistor R1 in series, namely an antenna L1. Voltage between the connection point 30 of the resistor R1 in the oscillation circuit and the inductance L1 and a ground 2m is measured. A measuring device comprises a capacitor storing voltage measured at a node 30. Voltage between both ends of the capacitor is dropped, as the distance between the terminal and a transponder increases. Voltage stored in the capacitor is sent to the processor of the terminal 1'.
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Patent Agency Ranking
公开(公告)号：JP2000341171A
公开(公告)日：2000-12-08
申请号：JP2000104891
申请日：2000-04-06
Applicant: ST MICROELECTRONICS SA
Inventor： WUIDART LUC , BARDOUILLET MICHEL , ENGUENT JEAN-PIERRE
Abstract: PROBLEM TO BE SOLVED: To reduce or minimize thermal effect relating to remote power supply to a transponder by a read/write terminal by detuning the oscillation circuits of a terminal and/or the transponder, when they are in a very closely coupled relation. SOLUTION: A read/write terminal 1' of an electromagnetic transponder is equipped with a means for causing an oscillation circuit to be detuned from the carrier frequency. The terminal 1' includes the oscillation circuit, which is located between the output terminal 2p of an amplifier, i.e., an antenna coupler 3 and a terminal 2m with a reference potential and composed of a capacity component 24, a resistance R1, and a series antenna L1. Then the phase of the current of the antenna L1 is adjusted with respect to a reference signal REF. This adjustment is an adjustment of a high-frequency signal, i.e., a carrier signal corresponding to a signal TX having no transmission data and carried out by varying the capacitance C1 of the oscillation circuit of the terminal 1' and holding the antenna current at constant phase relation with the reference signal REF.
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公开(公告)号：JP2000341884A
公开(公告)日：2000-12-08
申请号：JP2000104893
申请日：2000-04-06
Applicant: ST MICROELECTRONICS SA
Inventor： WUIDART LUC , BARDOUILLET MICHEL , ENGUENT JEAN-PIERRE
Abstract: PROBLEM TO BE SOLVED: To attain reduction in thermal effect related to remote power supply to a transponder through a readout/writing terminal, by detuning a transponder oscillating circuit when the transponder has a very close coupling relation to the readout/writing terminal. SOLUTION: This transponder 30 is constituted of a parallel oscillating circuit including an inductance L2 and a capacitor C2' between two terminals 11', 12' of the circuit. Between the terminals 11', 12', a capacitor C3 and a switch (for example, MOS transistor) K1 are serially connected. A switch K1 is controlled by a circuit 31 and is closed at the time of tuning operation. When it is in a closely coupled condition with the terminal, or respective antennas are positioned at a distance of less than 2 cm, for example, the oscillating circuit of the transponder is detuned (the switch K1 is off). It is thus possible to prevent heat generation of the transponder in radio-supplying operating power to the transponder approaching the terminal from the terminal.
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公开(公告)号：JP2000332647A
公开(公告)日：2000-11-30
申请号：JP2000104892
申请日：2000-04-06
Applicant: ST MICROELECTRONICS SA
Inventor： WUIDART LUC , BARDOUILLET MICHEL , ENGUENT JEAN-PIERRE
Abstract: PROBLEM TO BE SOLVED: To provide a method for duplex transmission between a terminal and a transponder in an electromagnetic transponder system. SOLUTION: Each of the terminal 40 and the transponder 10 is provided with an oscillation circuit 24, a modulation means and a demodulation means, the amplitude modulation transmission of a signal to be transmitted from the terminal 40 to the transponder 10 and the transmission of a signal from the transponder 10 to the terminal 40 and suited so as to follow the phase demodulation of the terminal 40 are simultaneously executed and an amplitude modulation rate is
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公开(公告)号：DE60041298D1
公开(公告)日：2009-02-26
申请号：DE60041298
申请日：2000-04-06
Applicant: ST MICROELECTRONICS SA
Inventor： WUIDART LUC , BARDOUILLET MICHEL , ENGUENT JEAN-PIERRE
Abstract: A terminal (40) and a transponder (10) contain a corresponding oscillating circuit (Li,Ci,24,L2,C2). An AM transmission of a signal sends a boundary-mark toward the transponder a signal (Rx) undergo a phase demodulation in the boundary-mark. The depth o modulation (tm) of the amplitude is lower than 100%. An Independent claim is included for: (a) a terminal for performing a claimed method (b) a transponder
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公开(公告)号：DE60040111D1
公开(公告)日：2008-10-16
申请号：DE60040111
申请日：2000-04-06
Applicant: ST MICROELECTRONICS SA
Inventor： WUIDART LUC , BARDOUILLET MICHEL , ENGUENT JEAN-PIERRE
Abstract: The transponder includes capacitor-transistor pairs (C3,K1,C4,K2) that produce an information when the transponder is close reading-writing terminal. The oscillating circuit of the transponder has a given frequency. The transmission of the information this position does not match since the frequency is higher than that of the oscillating circuit. An Independent claim is included for: (a) a system of data transmission
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