Patents by Inventor Ralph Spickerman

Ralph Spickerman 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).

  • Use of cross tap equalization to reduce crosstalk arising from inadequate optical filtering in a wavelength division multiplexed optical link
    Patent number: 6281995
    Abstract: Improved wavelength division multiplexed optical links and signal processing methods that employ cross tap equalization to reduce crosstalk arising from inadequate optical filtering. After optical filtering and photodetection, the wavelength division multiplexed signals adjacent either side of a signal whose crosstalk is to be reduced are sampled, weighted and are then subtracted from the signal whose crosstalk is to be reduced. This is done using adaptive correlation, performed simultaneously on all signals, each with respect to its respective adjacent channels. The present invention enables more closely spaced optical carriers to be used in the wavelength division multiplexed optical link.
    Type: Grant
    Filed: April 11, 2000
    Date of Patent: August 28, 2001
    Assignee: Lockheed Martin Corporation
    Inventors: Ralph Spickerman, Geoffrey S. Waugh