Patents by Inventor Joel F. Walker

Joel F. Walker 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: 7138953
    Abstract: A method of reducing blockage in a reflector antenna includes disposing a feed mechanism in front of a first reflector and disposing a second reflector in front of the feed mechanism. The second reflector permits energy to pass that would otherwise have been blocked from being received or transmitted by the first reflector. A reflector antenna is also formed in accordance with this method. Another method of reducing blockage in a reflector antenna includes disposing a first feed mechanism in front of a first reflector and disposing a second antenna in front of the first feed mechanism. The first feed mechanism blocks energy from being received or transmitted by the first reflector. The second antenna receives or transmits energy blocked by the first feed mechanism. A reflector antenna is also formed in accordance with this method.
    Type: Grant
    Filed: January 25, 2005
    Date of Patent: November 21, 2006
    Assignee: Malibu Research Associates
    Inventors: Joel F. Walker, Daniel G. Gonzalez
  • Patent number: 6882311
    Abstract: A receiver for a digital beamforming radar system includes a plurality of antenna elements, low-noise block converters, one or more analog-to-digital converters, and a processor. The antenna elements receive a radar signal and output a received signal. The low-noise block converters are modified commercially available components used in satellite television systems, respond to the received signal from a corresponding antenna element, and output an intermediate frequency signal. The low-noise block converters include at least one amplifier, a mixer, and a local oscillator input. The local oscillator input enables an external local oscillator signal to be inputted to the mixer. The analog-to-digital converters are responsive to the intermediate frequency signal of a corresponding low-noise block converter. The processor is responsive to the digital signals output by the analog-to-digital converters.
    Type: Grant
    Filed: April 12, 2002
    Date of Patent: April 19, 2005
    Assignee: Malibu Research Associates
    Inventors: Joel F. Walker, Daniel G. Gonzalez, Anand Kelkar, Norman Lamarra
  • Patent number: 6856301
    Abstract: A phased array antenna includes phase shifting elements, drivers, and antenna elements. The phase shifting elements are operatively coupled to first signals and second signals, and include at least one plasma electrode. The drivers selectively energize the plasma electrode and the phase shifting elements provide a phase shift between the first and second signals in response to the plasma electrode being energized. The antenna elements are operatively coupled to the phase shifting elements. A method of phase shifting an array antenna includes the steps of providing phase shifting elements operatively coupled to first signals and second signals, and incorporating at least one plasma electrode in the phase shifting elements. The method also includes the steps of selectively energizing the plasma electrode, shifting the phase between the first signals and second signals in response to the plasma electrode being energized, and operatively coupling antenna elements to the second signals.
    Type: Grant
    Filed: April 30, 2003
    Date of Patent: February 15, 2005
    Assignee: Malibu Research Associates
    Inventors: Joel F. Walker, Daniel G. Gonzalez
  • Publication number: 20030218575
    Abstract: A phased array antenna includes phase shifting elements, drivers, and antenna elements. The phase shifting elements are operatively coupled to first signals and second signals, and include at least one plasma electrode. The drivers selectively energize the plasma electrode and the phase shifting elements provide a phase shift between the first and second signals in response to the plasma electrode being energized. The antenna elements are operatively coupled to the phase shifting elements. A method of phase shifting an array antenna includes the steps of providing phase shifting elements operatively coupled to first signals and second signals, and incorporating at least one plasma electrode in the phase shifting elements. The method also includes the steps of selectively energizing the plasma electrode, shifting the phase between the first signals and second signals in response to the plasma electrode being energized, and operatively coupling antenna elements to the second signals.
    Type: Application
    Filed: April 30, 2003
    Publication date: November 27, 2003
    Inventors: Joel F. Walker, Daniel G. Gonzalez
  • Publication number: 20020171584
    Abstract: A receiver for a digital beamforming radar system includes a plurality of antenna elements, low-noise block converters, one or more analog-to-digital converters, and a processor. The antenna elements receive a radar signal and output a received signal. The low-noise block converters are modified commercially available components used in satellite television systems, respond to the received signal from a corresponding antenna element, and output an intermediate frequency signal. The low-noise block converters include at least one amplifier, a mixer, and a local oscillator input The local oscillator input enables an external local oscillator signal to be inputted to the mixer. The analog-to-digital converters are responsive to the intermediate frequency signal of a corresponding low-noise block converter. The processor is responsive to the digital signals output by the analog-to-digital converters.
    Type: Application
    Filed: April 12, 2002
    Publication date: November 21, 2002
    Inventors: Joel F. Walker, Daniel G. Gonzalez, Anand Kelkar, Norman Lamarra
  • Patent number: 6198457
    Abstract: A satellite communications antenna includes a low-windload reflector so that the antenna may be used on high windload locations, such as on a ship. The reflector has a support structure which includes a grid-like structure having relatively large apertures therein to allow wind to pass therethrough. The reflector further includes reflective radiators, such as dipoles, mounted to the support structure for focusing at least one desired frequency of operation. The reflector is also formed in component parts for easy assembly/disassembly should it be necessary to deploy the system elsewhere.
    Type: Grant
    Filed: October 9, 1998
    Date of Patent: March 6, 2001
    Assignee: Malibu Research Associates, Inc.
    Inventors: Joel F. Walker, Gerald E. Pollon, Daniel G. Gonzalez
  • Patent number: 5864322
    Abstract: An electronic scan antenna for generating an electrically scanned RF beam in response to an incident RF beam having at least one operating frequency band associated therewith includes a ground plane for reflecting the incident RF beam and a phasing arrangement of plasma structures operatively coupled to the ground plane. Each plasma structure includes gas containing areas which are reflective at the operating frequency range, when ionized, forming ionized plasma areas. Each ionized plasma area is disposed a first distance from the ground plane, a second distance from adjacent ionized plasma areas and each plasma ionized plasma area has a particular size associated therewith. In this manner, each ionized plasma area, in cooperation with the ground plane, provides a portion of a composite RF beam which has a phase shift associated therewith.
    Type: Grant
    Filed: January 23, 1997
    Date of Patent: January 26, 1999
    Assignee: Malibu Research Associates, Inc.
    Inventors: Gerald E. Pollon, Daniel G. Gonzalez, Joel F. Walker, Lawrence J. Sikora
  • Patent number: 5311200
    Abstract: A variable width waveguide scanner includes a pair of spaced apart waveguides defined by U-shaped sleeves each having an open end. A U-shaped plunger having spaced apart parallel first and second arms is coupled to the waveguides such that the arms are received by the open ends of the sleeves and are reciprocatingly slidable in the sleeves. A plurality of radiating elements in the form of spaced apart slots are formed in an end wall of each waveguide.
    Type: Grant
    Filed: July 7, 1993
    Date of Patent: May 10, 1994
    Assignee: Malibu Research Associates, Inc.
    Inventors: Joel F. Walker, Daniel G. Gonzalez, Gerald E. Pollon
  • Patent number: 4905014
    Abstract: The present invention concerns an electrically thin microwave phasing structure for electromagnetically emulating a desired reflective surface of selected geometry over an operating frequency band. The microwave phasing structure comprises a support matrix and a reflective means for reflecting microwaves within the frequency operating band. The reflective means is supported by the support matrix. An arrangement of electromagnetically-loading structures is supported by the support matrix at a distance from the reflective means which can be less than a fraction of the wavelength of the highest frequency in the operating frequency range. The electromagnetically-loading structures are dimensioned, oriented, and interspaced from each other and disposed at a distance from the reflective means, as to provide the emulation of the desired reflective surface of selected geometry.
    Type: Grant
    Filed: April 5, 1988
    Date of Patent: February 27, 1990
    Assignee: Malibu Research Associates, Inc.
    Inventors: Daniel G. Gonzalez, Gerald E. Pollon, Joel F. Walker