Patents by Inventor Ralph P. Trefney

Ralph P. Trefney 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: 5770950
    Abstract: In a data transmission system having a first and a second data transmission device and a transmission line that is not terminated, a method of minimizing signal reflection along the transmission line is described that includes the step of connecting the first and second data transmission devices to the transmission line such that the distance between the first and second data transmission devices is substantially proportional to a wavelength of a predetermined frequency. Data to be transmitted from the first data transmission device to the second data transmission device via the transmission line are encoded in the first data transmission device such that energy of the encoded data is substantially concentrated around the predetermined frequency to minimize the signal reflection without terminating the transmission line. A data transmission system with minimized signal reflection is also described.
    Type: Grant
    Filed: September 28, 1995
    Date of Patent: June 23, 1998
    Assignee: Cisco Systems, Inc.
    Inventors: Daniel F. Zurcher, Ralph P. Trefney
  • Patent number: 5046132
    Abstract: A calibrator circuit for a self-contained device for vertification of open field test site accuracy. This device generates a broadband width of discrete frequencies from 10 MHz to 1000 MHz which is then radiated into space. The circuit contains a power supply subcircuit, an oscillator subcircuit which generates an output signal rich in harmonics, an antenna radiating element and a balun network to couple the output from the oscillator subcircuit to the antenna element.
    Type: Grant
    Filed: May 19, 1989
    Date of Patent: September 3, 1991
    Assignee: C.K. Consultants, Inc.
    Inventor: Ralph P. Trefney
  • Patent number: 4070619
    Abstract: A VSWR meter unit for detecting and measuring the forward and reflected RF voltage wave signals on a coaxial transmission line. The unit is adapted to be electrically inserted in a tubular or coaxial transmission line, having an outer conductor with a coaxial center conductor therein. A microstrip circuit board is provided within the meter unit and comprises a dielectric board with a ground plane conductor printed on one side and inserted across the outer conductor, and a specially designed conductive path printed on the other side and inserted across the inner conductor. Also printed on the other side of the microstrip board is an inductive sensing loop located within and concentric with a circular loop portion of the conductive path. The sensing loop is closely spaced to the loop portion of the conductive path so as to be responsive to the voltage wave signal on the transmission line. A D'Arsonval meter movement is connected to the conductive loop through a specially designed 180.degree.
    Type: Grant
    Filed: February 14, 1977
    Date of Patent: January 24, 1978
    Assignee: Bird Electronic Corporation
    Inventor: Ralph P. Trefney