Patents by Inventor Randall R. Hillock

Randall R. Hillock 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: 5715520
    Abstract: The radio frequency transceiver was developed for use in a time division duplex (TDD) radiotelephone communication system. The transceiver includes a local oscillator which generates at least two local oscillator signals at different times. Each local oscillator signal has a unique frequency. During a first time period, the radio frequency transceiver receives a radio frequency signal. The first radio frequency signal is combined with one of the local oscillator signals, forming an intermediate frequency signal. During a second time period and substantially during the first time period, the transceiver generates a frequency offset signal. The frequency offset signal is combined with the second local oscillator signal, forming a second radio frequency signal. The intermediate frequency signal and the offset frequency signal are designed to have different frequencies to avoid the self-quieting problem inherent in a TDD communication system.
    Type: Grant
    Filed: January 20, 1995
    Date of Patent: February 3, 1998
    Assignee: Motorola, Inc.
    Inventors: Randall R. Hillock, John S. Ruppel