Patents by Inventor A. R. Lopez

A. R. Lopez 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: 5111208
    Abstract: In a system having plural signal-carrying channels, a phase shift is introduced between a signal in one of the channels and a reference signal for calibrating the individual channels. The reference signal is obtained by adding samples of signals in other ones of the channels. The phase shift is introduced by phase-shift apparatus responsive to a command signal directing a continuous monotonic increment of phase. The phase incrementing introduces a frequency shift (a serrodyne), which produces a beat-frequency signal for mixing a channel signal with the reference signal. The beat-frequency signal is phase locked to a modulation patern of a command signal, whereby a measurement of phase (or delay) can be made between the two signals for calibration of each channel within the system.
    Type: Grant
    Filed: February 23, 1989
    Date of Patent: May 5, 1992
    Assignee: Hazeltine Corporation
    Inventor: A. R. Lopez
  • Patent number: 4912480
    Abstract: An azimuthal scanning antenna for an aircraft landing system is formed of a set of vertically disposed columnar radiators arranged side-by-side in a horizontal array. The columnar radiators are tilted back in pitch 7.5.degree.. Individual ones of the radiators are formed of waveguide sections terminated by reflecting end walls. The terminating walls provide for a standing wave of electromagnetic field in response to microwave electromagnetic energy applied to the waveguide section by a feed disposed at or near the bottom of the waveguide section. Slot apertures are disposed along a front wall of each waveguide section, and are oriented at a selected angle relative to a perpendicular relationship to the sidewalls. The orientation of the slots introduces a variation in coupling for illumination of the radiation aperture of the radiator wherein the phase center is offset from a central point towards an upper end of each of the waveguide sections.
    Type: Grant
    Filed: October 14, 1988
    Date of Patent: March 27, 1990
    Assignee: Hazeltine Corporation
    Inventor: A. R. Lopez