Patents by Inventor James S. Lehnert

James S. Lehnert 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: 7751509
    Abstract: A technique for interference suppression in MC-CDMA systems is proposed which exploits the structural differences in signals that arrive at the receiver with Doppler shifts or carrier offsets. Oversampling the received signal in the frequency domain and properly combining the samples provides the interference suppression. Frequency domain oversampling is accomplished by using a time extension of the conventional MC-CDMA signal. Furthermore, a receiver structure is introduced that despreads and combines groups of samples so that a linear minimum mean-squared error solution for combining the groups is easily found. This combining scheme increases the signal-to-interference ratio (SIR) experienced by the desired user in the MC-CDMA system. In addition, the receiver performs well in severe near-far scenarios when there is sufficient Doppler separation between the signals of the desired user and an interferer.
    Type: Grant
    Filed: October 6, 2004
    Date of Patent: July 6, 2010
    Assignee: Purdue Research Foundation
    Inventor: James S. Lehnert