Patents Assigned to X-Com, Inc.
  • Patent number: 5406584
    Abstract: A digital modulation technique is disclosed which is unique in that it does not utilize fixed time slots for varying the characteristics of an electromagnetic carrier signal, but actually uses variations of the time slots to transfer the digital information. The modulation is created by using direct digital synthesis techniques to produce a carrier waveform that closely approximates a sine wave carrier signal that can vary the time it takes for each peak to occur. The peaks of the carrier are tightly controlled to occur at exact discrete time slots that correspond to certain base band digital data. The time slot changes occur precisely at the sine wave peaks to minimize the bandwidth requirement and maximize the data rate.
    Type: Grant
    Filed: September 1, 1992
    Date of Patent: April 11, 1995
    Assignee: X-Com, Inc.
    Inventor: David E. Erisman