Patents by Inventor David J Maddocks

David J Maddocks 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).

  • Safe repair of malfunction in optical communication system
    Patent number: 6483616
    Abstract: Following a fault in a bidirectional optical communication system, the lasers which generate traffic-carrying channels and a supervisory channel are shut down to permit personnel to effect repairs safely. The low power supervisory channel is pulsed on at intervals to determine if the fault is still present, but if a receiver is able correctly to restore frame alignment from such a pulse, the reverse direction supervisory channel is enabled, and following frame alignment in both directions, the main lasers are safely turned on.
    Type: Grant
    Filed: September 8, 1999
    Date of Patent: November 19, 2002
    Assignee: Marconi Communications Limited
    Inventors: David J Maddocks, Paul A Callan