Patents by Inventor Jean-Philippe Haag

Jean-Philippe Haag has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4355214
    Abstract: An echo canceller for a full-duplex carrier modulation transmission system terminal. The echo canceller includes a digital time-domain complex transversal filter with controlled weighting coefficients and an offset equal to a submultiple l of a Baud period .DELTA. related to a rate at which a stream of complex symbols is received at the input of the filter. These complex symbols include complex symbols outputted by a coder of a transmitter of the terminal at the rate l/.DELTA. interleaved with l-1 null symbols. The transversal filter output is connected to a digital modulator operated at the transmitter carrier frequency with instantaneous values updated at intervals equal to the Baud period to generate a passband echo copy signal. The invention is of particular benefit in transmission systems in which the product of the transmission carrier frequency and the Baud period is an integral multiple of l/4, as digital implementation of the modulator is then extremely simple.
    Type: Grant
    Filed: June 23, 1980
    Date of Patent: October 19, 1982
    Assignee: Compagnie Industrielle des Telecommunications Cit-Alcatel
    Inventors: Michel Levy, Jean-Philippe Haag