Patents Examined by Robert L. Griffith
  • Patent number: 4829543
    Abstract: A method and apparatus for phase-coherently demodulating a multipath-impaired time division multiple access QPSK data timeslot is disclosed. A quadrature separator generates multipath-impaired intermediate signals which, during a predetermined synchronizing sequence for the timeslot, are applied to a pair of synchronizing correlators to generate quadrature multipath profiles. These profiles then are used to modify subsequently received QPSK timeslot signals at the separator outputs to coherently construct multipath compensated I and Q channel data.
    Type: Grant
    Filed: December 4, 1987
    Date of Patent: May 9, 1989
    Assignee: Motorola, Inc.
    Inventors: David E. Borth, Chih-Fei Wang, Duane C. Rabe, Gerald P. Labedz