Patents by Inventor Ulrich Liefländer

Ulrich Liefländer 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).

  • Method for testing subscriber access lines
    Patent number: 7286952
    Abstract: A method for testing subscriber access lines wherein the test is carried out locally, online and virtually all the time with the assistance of the digital signal processor for the subscriber line. The test results are gathered at a central point and are signaled from there; when required, to specific locations in the subscriber access network, for example, to a distribution node where maintenance work is currently being carried out.
    Type: Grant
    Filed: September 27, 1999
    Date of Patent: October 23, 2007
    Assignee: Siemens Aktiengesellschaft
    Inventors: Svend Christensen, Ludwig Dirscherl, Ulrich Liefländer, Hans-Werner Rudolf, Franz Schmöller