Patents by Inventor Michael Herbert Retzer

Michael Herbert Retzer 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: 6009325
    Abstract: A unique method and apparatus automatically switches between a voice mode and a data mode in a wireless communication device. In particular, a communication device (200) adapted to voice and data signals monitors a data network for data traffic for a first predetermined period of time (506), then monitors a cellular control channel (516) for cellular traffic during a sleep mode of the data network before establishing normal cellular operation. The method and apparatus increases efficient use of channel capacity by selectively switching between systems during periods of nonuse. Finally, according to other novel aspects of the present invention, user prompts (606, 618) enable efficient use of a communication device capable of transmitting and receiving both voice and data.
    Type: Grant
    Filed: February 1, 1995
    Date of Patent: December 28, 1999
    Assignee: Motorola, Inc.
    Inventors: Michael Herbert Retzer, Manohar Achyut Joglekar
  • Patent number: 5757859
    Abstract: An apparatus and method for recovering packet data with unknown delays and error transients is disclosed that includes a received waveform containing a desired information signal relative to a fixed reference, for eliminating an undesired error in the received waveform where the error is localized in time relative to the received waveform to a transient interval, and recovering the desired information signal. Included also is a sampler, responsive to the received waveform, providing a series of time samples representative of the received waveform. A buffer, responsive to the time samples, for providing a plurality of representations of the received waveform at different instants of time, where the length of time is an appreciable duration of a transient interval. A reference slicker, responsive to the plurality of representations, for providing an estimate of a fixed reference.
    Type: Grant
    Filed: February 27, 1996
    Date of Patent: May 26, 1998
    Assignee: Motorola Inc.
    Inventors: Michael Herbert Retzer, Andrew Scott Lundholm
  • Patent number: 5737369
    Abstract: An apparatus and method for recovering data in the presence of error transients is disclosed that includes a received waveform containing an information signal encoded at periodic time instants of a known period for eliminating an undesired amplitude error in the received waveform, where the error is slowly varying with respect to the known periods and recovering the desired periodic time instants. A delay element for delaying the received waveform by an amount equal to the period is included and a subtracting element for comparing the received waveform with the delayed waveform, and providing a timing recovery signal with zero crossing substantially less corrupted by the undesired amplitude error, and an averaging circuitry operating on the timing recovery signal for purposes of recovering the desired periodic time instants aids in recovering data in the presence of error transients.
    Type: Grant
    Filed: February 28, 1996
    Date of Patent: April 7, 1998
    Assignee: Motorola, Inc.
    Inventor: Michael Herbert Retzer