Patents by Inventor Richard A. Stern

Richard A. Stern 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: 5144320
    Abstract: An antenna array includes several antenna elements, each having a microstrip transmission line which includes a strip conductor and a ground plane conductor separated by a dielectric substrate; an antenna portion of the substrate being adapted to enable energy within the substrate to radiate away from the microstrip transmission line. The substrate may have greater capacitance at the antenna portion than other portions of the substrate. The antenna portion is adapted to permit RF energy to the microstrip transmission line to be directionally radiated away from the microstrip transmission line at the antenna portion, the direction of radiation being a function of the frequency of the supplied energy and the antenna slot separation. The individual antenna elements are connected, preferably in pairs, to switching elements, preferably microstrip-type circulators, providing a switchable transmission path from an RF input to a selected antenna element.
    Type: Grant
    Filed: February 10, 1992
    Date of Patent: September 1, 1992
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Richard A. Stern, Richard W. Babbitt
  • Patent number: 4887054
    Abstract: A latching type of microstrip reciprocal phase shifter is provided having a oroidal-shaped ferrite core with a length of microstrip conductor wound about the outer cylindrical surface of the core and a ground plane mounted on the inner cylindrical surface of the core surrounding the aperture in the core. A single control wire is passed through the aperture in the core and creates a circular magnetic field in the core surrounding the aperture when the core is pulsed with a unidirectional current pulse.
    Type: Grant
    Filed: December 23, 1988
    Date of Patent: December 12, 1989
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Richard A. Stern, Richard W. Babbitt
  • Patent number: 4881052
    Abstract: A microstrip nonreciprocal latching phase shifter has a ferrite rod with ramp-shaped dielectric waveguide members at the ends thereof mounted on one surface of a microstrip dielectric substrate having a ground plane on the opposite surface thereof. The dielectric constants of the ramp members and the rod are substantially the same and the substrate dielectric constant is substantially less than the dielectric constant of the ramp members. A dielectric plate is on top of the rod. A microstrip conductor mounted on the substrate, the ramp members and the plate in axial alignment with the rod extends between the ends of the substrate. The rod has a rectangular longitudinally-extending passageway therein filled by a dielectric core insert having a dielectric constant greater than the dielectric constant of the rod. A single control wire is disposed in and aligned with the core insert.
    Type: Grant
    Filed: December 5, 1988
    Date of Patent: November 14, 1989
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Richard A. Stern, Richard W. Babbitt
  • Patent number: 4879562
    Abstract: A microstrip antenna is improved by applying a thin coating of ferrite maial to the surface of the metal ground plane of the antenna by flame spraying or arc plasma spraying. The applied ferrite coating is not exposed to a high temperature anneal cycle.
    Type: Grant
    Filed: January 9, 1989
    Date of Patent: November 7, 1989
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Richard A. Stern, Richard W. Babbitt
  • Patent number: 4862117
    Abstract: A millimeter wave microstrip Y-junction circulator is provided comprising a ection of microstrip dielectric substrate having a cone-shaped ferrite element mounted on one side thereof together with three, Y-junction oriented sections of microstrip conductor extending from the base of the ferrite element and an electrically conductive ground plane mounted on the other side thereof. The ferrite element is covered with a cone-shaped microstrip conductor which electrically interconnects the three Y-oriented sections of microstrip conductor. When the ferrite element is fabricated of a spinel type of ferrite, a small permanent magnet is mounted on the ground plane beneath the ferrite element to provide a unidirectional magnetic field which produces a circulator action with respect to RF energy applied to the three sections of microstrip conductor.
    Type: Grant
    Filed: January 27, 1989
    Date of Patent: August 29, 1989
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Richard A. Stern, Richard W. Babbitt
  • Patent number: 4845449
    Abstract: A microstrip switch is provided comprising a rectangular ferrite rod having pair of ramp-shaped dielectric waveguide members at the ends thereof. The ramp members are made of dielectric waveguide material having a dielectric constant which is substantially the same as the dielectric constant of the ferrite. The rod and ramp members are mounted on one surface of a microstrip dielectric substrate having a dielectric constant substantially less than the dielectric constant of the ramp members and a ground plane on the other surface thereof. Input and output sections of microstrip conductor are mounted on the surface of the substrate and the sloping surfaces of the ramp members in axial alignment with the rod and ramp members.
    Type: Grant
    Filed: November 3, 1988
    Date of Patent: July 4, 1989
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Richard A. Stern, Richard W. Babbitt
  • Patent number: 4843357
    Abstract: A tetrahedral junction waveguide switch is provided having two axially juxtaposed sections of hollow rectangular waveguide which are mutually cross-polarized by being rotated 90 degrees with respect to each other. A rod of a ferrite material having gyromagnetic properties is axially disposed within the juxtaposed ends of the waveguide sections and is selectively axially magnetized to control transmission of RF electromagnetic wave energy through the sections. A permanent magnet structure having a unique cladding arrangement which minimizes flux leakage and produces a magnet of high coercive force is employed to produce a unidirectional magnetic bias field along the longitudinal axis of the rod to keep the switch in a low loss transmission state by virtue of Reggia-Spencer effect signal rotation. A selectively operable helical coil is utilized to produce another axial magnetic field which nullifies the bias magnetic field when it is desired to place the switch in a high loss or cut-off transmission state.
    Type: Grant
    Filed: October 20, 1988
    Date of Patent: June 27, 1989
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Richard A. Stern, Herbert A. Leupold
  • Patent number: 4839659
    Abstract: A microstrip phase scan antenna array is provided having a columnar array microstrip radiating patches mounted on a dielectric substrate. Each column of the array is fed by a separate variable, reciprocal ferrite rod phase shifter which is mounted on the substrate and is coupled to the column which it controls and to a source of millimeter wave energy by microstrip to dielectric waveguide transitions. Each of the phase shifters is controlled by a helical biasing coil surrounding the ferrite rod. All of the biasing coils are serially interconnected by a single scanning control drive wire and the numbers of turns of the coils are related to each other by an arithmetic progression in which the number of turns of a particular biasing coil differs from the number of turns of the adjacent biasing coil in the sequence of biasing coils controlling the array by a constant amount.
    Type: Grant
    Filed: August 1, 1988
    Date of Patent: June 13, 1989
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Richard A. Stern, Richard W. Babbitt
  • Patent number: 4816787
    Abstract: A microstrip reciprocal phase shifter is provided comprising a rectangular ferrite rod having an upwardly sloping ramp member at one end thereof and a downwardly sloping ramp member at the other end thereof. The ramp members are made of dielectric waveguide having a dielectric constant substantially the same as the dielectric constant of the rod. The rod and ramp members are disposed on one surface of a microstrip dielectric substrate having a dielectric constant substantially lower than the dielectric constant of the ramp members and a ground plane on the other surface thereof. Input and output sections of microstrip conductor are placed on the surface of the substrate in axial alignment with the rod and ramp members.
    Type: Grant
    Filed: February 3, 1988
    Date of Patent: March 28, 1989
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Richard A. Stern, Richard W. Babbitt
  • Patent number: 4806886
    Abstract: A microstrip resonance isolator is provided comprising a dielectric waveguide element which is mounted on the top surface of a length of microstrip transmission line dielectric substrate having an electrically conductive ground plane on the bottom surface of the substrate. The waveguide element has a rectangular rod-shaped central section and two oppositely-inclined ramp-shaped sections at the ends of the central section. The dielectric constant of the waveguide element is substantially more than the dielectric constant of the microstrip transmission substrate. A microstrip conductor is provided on the top surface of the substrate from one end thereof to the other end thereof and passes over the top surface of the dielectric waveguide element. A thin, rectangular substrate of hexagonal, grain-oriented ferrite material is mounted on one side of the waveguide element between the ramp-shaped end sections.
    Type: Grant
    Filed: March 1, 1988
    Date of Patent: February 21, 1989
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Richard A. Stern, Richard W. Babbitt
  • Patent number: 4785304
    Abstract: A phase scan antenna array for planar radar scanning in a single plane with pencil-shaped beam is provided comprising a plurality of ferrite rod line source antennas. Each rod antenna has a plurality of beam-emitting slots spaced along one side thereof and is end fed in phase with the other antennas from a single hollow metallic waveguide by means of coupling slots in the waveguide which are spaced apart one wavelength of the radar frequency. The rods are mounted in a two-dimensional columnar array with the beam-emitting slots of each rod aligned in rows with the corresponding slots of the other rods by a mounting member having a plurality of mutually-parallel slots in which the rods are disposed. The walls of the mounting member slots suppress Faraday rotation of the waves in the rods and the bottom of the slots enhance the single beam emitted from the face of the array.
    Type: Grant
    Filed: November 20, 1986
    Date of Patent: November 15, 1988
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Richard A. Stern, Richard W. Babbitt, Gerald F. Mikucki
  • Patent number: 4777454
    Abstract: A switchable dielectric waveguide circulator is provided for millimeter wave frequency applications comprising a ferrite right prism having two polygonal prism bases and at least three lateral prism faces. A control wire is threaded through a number of bores formed in the prism in a plane between the bases. Each of the bores is spaced a distance from a different one of the apices of the prism so that a control current passing through the control wire creates a circular magnetic field about each bore which combine to form a resultant magnetic field between the prism bases which cause the prism faces to act as circulator ports. The rotational direction of circulator coupling action is reversed by reversing the direction of the control current. Both Y-junction and T-junction circulator configurations are shown.
    Type: Grant
    Filed: July 6, 1987
    Date of Patent: October 11, 1988
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Richard A. Stern, Richard W. Babbitt
  • Patent number: 4755827
    Abstract: A millimeter wavelength monolithic ferrite circulator/antenna device is pided comprising a four-sided ferrite rod having one end which is to be selectively coupled to millimeter wavelength radar transmitter and receiver apparatus and the other end coupled to a load. The rod end coupled to the radar apparatus has a pair of permanent magnets disposed on opposite sides of the rod and is shaped as a right prism having prism bases formed by sections of the rod sides on which the magnets are mounted and prism faces formed by sections of the remaining two rod sides and by the cross-section of the rod itself. The dc magnetic field produced by the magnets is perpendicular to the longitudinal axis of the rod and causes the prism to act as a ferrite circulator with respect to millimeter wave energy transmitted through the prism faces and along such rod axis. The remainder of the rod is utilized as a ferrite rod antenna of the leaky-wave type by providing energy emitting perturbations on one of the rod sides.
    Type: Grant
    Filed: February 4, 1987
    Date of Patent: July 5, 1988
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Richard A. Stern, Richard W. Babbitt
  • Patent number: 4754237
    Abstract: A millimeter wave switchable microstrip Y-junction circulator is provided comprising a monlithic, wye-shaped ferrite element disposed on one surface of a section of microstrip dielectric substrate having three, Y-junction oriented sections of microstrip conductor on the same one substrate surface and an electrically conductive ground plane on the opposite substrate surface. The ferrite element has a central right prism-shaped portion with two equilateral triangular-shaped prism bases and three rectangular prism faces and three downwardly-sloping arm portions which extend radially outwardly from the prism faces of the central portion. The top base of the ferrite element central portion and the top surface of the ferrite arm portions which do not rest on the substrate are provided with microstrip conductors which cooperate with the ground plane to convey millimeter wave signals applied to the three Y-junction oriented microstrip sections on the substrate to the ferrite element central portion.
    Type: Grant
    Filed: September 21, 1987
    Date of Patent: June 28, 1988
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Richard A. Stern, Richard W. Babbitt
  • Patent number: 4749966
    Abstract: A millimeter wave microstrip Y-junction circulator is provided comprising a monolithic, wye-shaped ferrite element disposed on one surface of a section of microstrip dielectric substrate having three, Y-junction oriented sections of microstrip conductor on the same one substrate surface and an electrically conductive ground plane on the opposite substrate surface. The ferrite element has a central right prism-shaped portion with two equilateral triangular-shaped prism bases and three rectangular prism faces and three downwardly-sloping arm portions which extend radially outwardly from the prism faces of the central portion. The top base of the ferrite element central portion and the top surface of the ferrite arm portions which do not rest on the substrate are provided with microstrip conductors which cooperate with the ground plane to convey millimeter wave signals applied to the three Y-junction oriented microstrip sections on the substrate to the ferrite element central portion.
    Type: Grant
    Filed: July 1, 1987
    Date of Patent: June 7, 1988
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Richard A. Stern, Richard W. Babbitt
  • Patent number: 4746926
    Abstract: A phase scan antenna suitable for millimeter wave radar applications is pided comprising a four-sided ferrite rod having a series of electromagnetic energy emitting slots along one side of the rod. The remaining three rod sides are enclosed by a metal, channel-shaped member which is spaced from the rod by a plastic, channel-shaped substrate member, so that energy emitted from the rod side which is opposite from the slotted rod side will be reflected to pass out the slotted rod side, to thereby enhance the antenna beam produced by the slotted rod side. A magnetic biasing coil having serially-interconnected coil portions is helically wound about the metal channel-shaped member with the coil portions disposed between the slots in the first rod side to cause scanning of the antenna beam. The ferrite rod may be end fed by either dielectric waveguide sections or hollow, metallic waveguide sections.
    Type: Grant
    Filed: September 29, 1986
    Date of Patent: May 24, 1988
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Richard A. Stern, Richard W. Babbitt, John J. Borowick
  • Patent number: 4745377
    Abstract: A microstrip to dielectric waveguide transition is provided comprising a gth of rectangular dielectric waveguide which has one end tapered in such a manner that the height of the waveguide top surface above the waveguide bottom surface decreases linearly from full height to zero height at the tapered end of the length of waveguide. The bottom surface of the waveguide length is mounted on the top surface of a planar microstrip dielectric substrate having an electrically conductive metallic ground plane on the bottom substrate surface and a length of microstrip conductor on the top substrate surface aligned with the waveguide length and abutting the tapered end of the waveguide length. A second length of microstrip conductor is mounted on the tapered portion and part of the untapered portion of the top surface of the waveguide length and is electrically connected to the first microstrip conductor at the tapered end of the waveguide length.
    Type: Grant
    Filed: June 8, 1987
    Date of Patent: May 17, 1988
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Richard A. Stern, Richard W. Babbitt
  • Patent number: H470
    Abstract: A millimeter-wave circulator for microstrip use. The device employs an hexagonal ferrite element to selectively direct the propagation of electromagnetic energy through a Y-junction circulator. The device does not require an external biasing magnet and provides improved bandwidth for high frequency operation.
    Type: Grant
    Filed: July 18, 1986
    Date of Patent: May 3, 1988
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Richard A. Stern, Richard W. Babbitt
  • Patent number: H639
    Abstract: A ferrite element for millimeter-wave ferrite control devices is made by -plasma-spraying ferrite material into a mold type cavity having the configuration of the desired ferrite element.
    Type: Grant
    Filed: May 2, 1988
    Date of Patent: June 6, 1989
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Richard A. Stern, Richard W. Babbitt
  • Patent number: H781
    Abstract: In the manufacture of a ferrite circulator, a ferrite material is introdu into the cavity area of a microstrip circuit or substrate by arc plasma spraying, thus eliminating any chance of gaps between ferrite material and microstrip circuit material.
    Type: Grant
    Filed: March 21, 1988
    Date of Patent: May 1, 1990
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventors: Richard A. Stern, Richard W. Babbitt