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    DETECTION D'ERREURS DANS UN SIGNAL EN MODULATION D'AMPLITUDE
    1.
    发明专利
    DETECTION D'ERREURS DANS UN SIGNAL EN MODULATION D'AMPLITUDE 未知

    公开(公告)号：FR2879382A1

    公开(公告)日：2006-06-16

    申请号：FR0452954

    申请日：2004-12-14

    Applicant: ST MICROELECTRONICS SA

    Inventor： ENGUENT JEAN PIERRE

    IPC: H04L1/24 ,  G06K7/00 ,  H04L27/02

    Abstract: L'invention concerne un procédé et un circuit de détection d'un taux de modulation dans un signal reçu en modulation d'amplitude, consistant à comparer le signal reçu par rapport à deux premières valeurs (VM-ref1, VM+ref1), à comparer le signal reçu par rapport à deux deuxièmes valeurs (VM-ref2, VM+ref2) comprises entre les deux premières valeurs, et à considérer la présence d'une profondeur de modulation insuffisante si le signal reçu est compris entre au moins deux desdites valeurs.

    3.
    发明专利
    未知

    公开(公告)号：FR2792136B1

    公开(公告)日：2001-11-16

    申请号：FR9904549

    申请日：1999-04-07

    Applicant: ST MICROELECTRONICS SA

    Inventor： WUIDART LUC ,  BARDOUILLET MICHEL ,  ENGUENT JEAN PIERRE

    IPC: G06K19/07 ,  G06K7/00 ,  G06K17/00 ,  H04B1/59 ,  H04B5/02 ,  H04B7/14

    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

    6.
    发明专利
    未知

    公开(公告)号：FR2792135A1

    公开(公告)日：2000-10-13

    申请号：FR9904548

    申请日：1999-04-07

    Applicant: ST MICROELECTRONICS SA

    Inventor： WUIDART LUC ,  BARDOUILLET MICHEL ,  ENGUENT JEAN PIERRE

    IPC: G06K7/00 ,  G06K19/07 ,  G01S13/74 ,  H04B1/59 ,  H04B5/02 ,  H04B7/14

    Abstract: The coupling between transponder and terminal is reduced by altering the resonant frequency of either the terminal or transponder coupling circuits when the two are in close proximity. When the coupling is reduced, the data rate for the communication between terminal and transponder is automatically increased, which can be achieved because the coupling is effectively a transformer coupling.

    8.
    发明专利
    未知

    公开(公告)号：FR2796781A1

    公开(公告)日：2001-01-26

    申请号：FR9909563

    申请日：1999-07-20

    Applicant: ST MICROELECTRONICS SA

    Inventor： WUIDART LUC ,  ENGUENT JEAN PIERRE

    IPC: G06K7/08 ,  G06K19/07 ,  H04B1/59 ,  H04B5/00

    Abstract: The system comprises a reading-writing terminal with a series oscillator circuit (R1, L1, C1) generating an electromagnetic field, and a transponder containing a parallel oscillator circuit (L2, C2) excited by the field of the terminal. The two oscillator circuits are dimensioned so that the coupling coefficient (k) rapidly decreases when the distance (d) between the transponder and the terminal deviates from a predetermined value. The critical distance value is e.g. 1 cm. The parallel oscillator circuit can contain no capacitor (C2), and the parasitic capacitance of inductor (L2) can have the role of capacitor. The inductance (L2) is maximized, and the capacitance (C2) is minimized. The inductance (L2) is chosen so to satisfy the relation; kopt - (R1L2/R2L1) , where kopt is the value of coupling coefficient giving the maximum voltage (V2max) on poles of parallel oscillator circuit, and R2 is an equivalent resistance of transponder connected in parallel with the inductance (L2). The components of parallel oscillator circuit (L2, C2) are dimensioned starting from a point of functioning at null distance, chosen to correspond to a value of coupling coefficient (k) below the optimum value (kopt) and satisfying the relation: V2max = R2/R1)

    9.
    发明专利
    未知

    公开(公告)号：FR2792132A1

    公开(公告)日：2000-10-13

    申请号：FR9904544

    申请日：1999-04-07

    Applicant: ST MICROELECTRONICS SA

    Inventor： WUIDART LUC ,  BARDOUILLET MICHEL ,  ENGUENT JEAN PIERRE

    IPC: G06K19/07 ,  G06K7/00 ,  G06K17/00 ,  H02J17/00 ,  H04B1/59 ,  H04B5/02 ,  H04B7/14

    Abstract: The terminal (1) uses inductive coupling to read from and write to a transponder, and includes a resonant circuit (Li,Ci) tuned to receive an AC HF excitation voltage. The resonant frequency may be altered so as to detune the LC in the event that a transponder is very close to the terminal. A capacitor (24) may be controlled by a control circuit (21) and with impedance (Li) to detect a gap of phase in relation to the signal of REF reference and to modify the capacity Ci of the capacitor (24). An Independent claim is included for a contactless system of data transmission.

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