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    DSL TRANSMISSION SYSTEM HAVING MEANS INSURING ORTHOGONALITY OF NEAR END ECHO
    1.
    发明专利
    DSL TRANSMISSION SYSTEM HAVING MEANS INSURING ORTHOGONALITY OF NEAR END ECHO 失效

    公开(公告)号：JP2000299650A

    公开(公告)日：2000-10-24

    申请号：JP2000059264

    申请日：2000-03-03

    Applicant: ST MICROELECTRONICS SA ,  TELIA AB

    Inventor： ISSON OLIVIER ,  NORDSTROEM TOMAS

    IPC: H04L5/14 ,  H04B3/21 ,  H04B3/23 ,  H04J11/00 ,  H04L25/03 ,  H04L27/26 ,  H04M1/76 ,  H04M3/00

    Abstract: PROBLEM TO BE SOLVED: To obtain a DSL transmission system of simple constitution by setting a period for processing a filter to an at least previously set time length. SOLUTION: An output symbol system S is subtracted from the output of a delay line 80 by a subtracting circuit 82, and a difference signal is supplied to an FIR filter 84 for realizing a transfer function h* for local echo inference. A filter 84 operates only to sampling data corresponding to a delaying time δor the maximum delaying time of a line and infers echo component from the difference between two continuous symbols. However, being a linear filter, the component is equivalent to the difference between the respective echo components of the two symbols. The output of the filter 84 is supplied for an adding circuit 86, and an input symbol S' receiving the influence of a nonlinear echo is simultaneously received. The circuit 86 supplies a desired orthogonal echo signal to a Fast Fourier Transforming(FFT) circuit 18 as an input signal IN'. Then, the filter 84 operates only in a short period at the starting point of each transmission symbol.

    DSL TRANSMISSION SYSTEM FOR COMPENSATING FAR-EDGE CROSSTALK
    2.
    发明专利
    DSL TRANSMISSION SYSTEM FOR COMPENSATING FAR-EDGE CROSSTALK 失效

    公开(公告)号：JP2001237747A

    公开(公告)日：2001-08-31

    申请号：JP2000377457

    申请日：2000-12-12

    Applicant: ST MICROELECTRONICS SA ,  ST MICROELECTRONICS NV

    Inventor： NORDSTROEM TOMAS ,  BENGTSSON DANIEL ,  ISSON OLIVIER

    IPC: H04J11/00 ,  H04B1/62 ,  H04B3/32 ,  H04L25/03 ,  H04L27/26

    Abstract: PROBLEM TO BE SOLVED: To provide a canceller circuit which can eliminate far-edge crosstalks, in a digital subscriber circuit transmission system. SOLUTION: This system includes a pre-compensation means which multiplies a vector S=(Si), where i is equal to 1 to n by a pre-compensation matrix M prior to transmission, so as to obtain a diagonal matrix product H*M. In this example, H is a transmission matrix of plural transmission channels as prescribed by R=H*S and R=(Ri), where i is equal to 1 to n is a vector of discrete multi-tone symbol Ri that is received by a modem. Such a system configuration is attained by a far-edge crosstalk eliminating circuit.

    4.
    发明专利
    未知

    公开(公告)号：DE602007000156D1

    公开(公告)日：2008-11-20

    申请号：DE602007000156

    申请日：2007-02-27

    Applicant: ST MICROELECTRONICS SA

    Inventor： ISSON OLIVIER ,  BELVEZE FABRICE ,  AOURIK FATIMA

    IPC: H04L25/02 ,  H04L27/26

    Abstract: The method involves determining a set of estimations of a transfer function of a transmission channel from another set of estimations obtained for pilots having a carrier frequency, for carriers and for frequency positions of considered carriers of symbols of a signal comprising pilots. A third estimation is determined from the former set of estimations, where the former set of estimations is determined from the third estimation determined for a symbol carrier that is received before the symbol at a same frequency as that of the carrier. An independent claim is also included for a coded orthogonal frequency division multiplex (COFDM) demodulator that receives successive symbols of a signal received from a transmission channel.

    RECEPTEUR AVEC CIRCUIT D'ESTIMATION DE CANAL.
    5.
    发明专利
    RECEPTEUR AVEC CIRCUIT D'ESTIMATION DE CANAL. 未知

    公开(公告)号：FR2938137A1

    公开(公告)日：2010-05-07

    申请号：FR0857422

    申请日：2008-10-31

    Applicant: ST MICROELECTRONICS SA

    Inventor： BELVEZE FABRICE ,  ISSON OLIVIER

    IPC: H04B1/707 ,  H04L25/02

    Abstract: L'invention concerne un circuit de réception pour démoduler un signal d'entrée reçu d'un canal de transmission, le circuit de réception comprenant un filtre d'interpolation agencé pour fournir des estimations (H ) du canal complet, et comprenant au moins un filtre (408, 412, 416) recevant des estimations du canal de fréquence pilote et effectuant un filtrage basé sur une pluralité (Q) des estimations du canal pilote à un instant donné, et une mémoire (422) agencée pour mémoriser les coefficients de filtrage pour ledit au moins un filtre, les coefficients étant basés sur une autocorrélation dans le domaine fréquentiel d'un modèle du canal de transmission, le modèle représentant la distribution temporelle de la puissance du canal de transmission déterminée indépendamment des estimations du canal de fréquence pilote.

    6.
    发明专利
    未知

    公开(公告)号：DE69915082D1

    公开(公告)日：2004-04-01

    申请号：DE69915082

    申请日：1999-12-14

    Applicant: ST MICROELECTRONICS NV ,  ST MICROELECTRONICS SA

    Inventor： NORDSTROEM THOMAS ,  BENGTSSON DANIEL ,  ISSON OLIVIER

    IPC: H04J11/00 ,  H04B1/62 ,  H04B3/32 ,  H04L25/03 ,  H04L27/26

    Abstract: The invention relates to a far-end crosstalk (FEXT) canceling circuit for a digital subscriber line transmission system, said transmission system comprising a plurality n of line termination (LT) modems (Mi) transmitting discrete multitone (DMT) symbols Si to corresponding network (NT) termination modems (Mc(i)) over n transmission channels. The invention proposes to multiply the vector S = (Si) i = 1 to n, before transmission, by a precompensation matrix M such that the matrix product H*M is diagonal, H being the transfer matrix of the n downstream transmission channels defined by R = H*S where R = (Ri), i = 1 to n, is the vector of the DMT symbols Ri respectively received by the modems Mc(i).

    9.
    发明专利
    未知

    公开(公告)号：FR2825862A1

    公开(公告)日：2002-12-13

    申请号：FR0107395

    申请日：2001-06-06

    Applicant: ST MICROELECTRONICS SA

    Inventor： ISSON OLIVIER

    IPC: H04J11/00 ,  H04B1/7087 ,  H04L5/02 ,  H04B3/54 ,  H04L27/36

    Abstract: A power line CDMA (Code Division Multiplex Access) data system transmits from each node (Nk) data multiplied by the assigned spreading matrix as OFDM (Orthogonal Frequency Division Multiplex) symbols on a group of carriers with cyclic prefix (PF) and suffix (SF) representing the predetermined number of samples with prefix and suffix subtracted from the received data used in a training phase.

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