Patents by Inventor Steven F Swanchara

Steven F Swanchara 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: 6690713
    Abstract: A tracking circuit fine tunes the sampling time to a resolution of ⅛ Tc, where Tc is a chip duration after the searcher circuit finds the timing to within 0.5 Tc. Depending on the prior art tracking circuit that is being used, the input signals are early and late sampled PN despread pilot symbols or early, late and ontime sampled PN despread pilot symbols. Early and late samples are plus or minus one tick or Tt (one tick is ⅛ Tc) away from the ontime samples. The basic principle is that if early and late samples have about the same energy, then the timing is correct. If not, then the sampling time is changed to obtain a balance. In this invention, improved performance of the prior art tracking circuit is obtained by using pilot estimation results, not ontime pilot symbols. In one embodiment, pilot estimation results are low pass filtered signals of ontime symbols which are normally generated upstream of the tracking circuit.
    Type: Grant
    Filed: June 19, 2000
    Date of Patent: February 10, 2004
    Assignee: Lucent Technologies Inc.
    Inventors: Jaehyeong Kim, Steven F Swanchara