Patents by Inventor John Sitch

John Sitch 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).

  • Sample timing control in an optical receiver
    Patent number: 7894728
    Abstract: A method of compensating phase error between parallel digital signals of a received optical signal, in a coherent optical receiver. A phase differential between the digital signals is determined. A digital skew is imposed between the digital signals, an amount of skew imposed being an integer number of sample periods calculated to most nearly compensate the phase differential. The skewed digital signals are then digitally processed, in the frequency domain, to compensate a residual portion of the phase differential.
    Type: Grant
    Filed: October 17, 2006
    Date of Patent: February 22, 2011
    Assignee: Ciena Corporation
    Inventors: Han Sun, Chandra Bontu, Kim B. Roberts, John Sitch, John Wolczanski