Patents by Inventor Sami G. Tantawi

Sami G. Tantawi 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: 11817612
    Abstract: A non-reciprocal microwave network is provided that includes an in-line ferromagnetic element with adjoining polarizing adapters to achieve directivity via a multi-mode interaction at or near the ferrite to act as new class of 4-port circulator or 2-port isolator, with standard waveguide inputs for assembly in larger networks.
    Type: Grant
    Filed: November 30, 2021
    Date of Patent: November 14, 2023
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Matthew A. Franzi, Sami G. Tantawi
  • Publication number: 20220115758
    Abstract: A non-reciprocal microwave network is provided that includes an in-line ferromagnetic element with adjoining polarizing adapters to achieve directivity via a multi-mode interaction at or near the ferrite to act as new class of 4-port circulator or 2-port isolator, with standard waveguide inputs for assembly in larger networks.
    Type: Application
    Filed: November 30, 2021
    Publication date: April 14, 2022
    Inventors: Matthew A. Franzi, Sami G. Tantawi
  • Patent number: 11258149
    Abstract: A non-reciprocal microwave network is provided that includes an in-line ferromagnetic element [1010] with adjoining polarizing adapters [1002, 1004, 1006, 1008] to achieve directivity via a multi-mode interaction at or near the ferrite to act as new class of 4-port circulator or 2-port isolator, with standard waveguide inputs for assembly in larger networks.
    Type: Grant
    Filed: February 14, 2019
    Date of Patent: February 22, 2022
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Matthew A. Franzi, Sami G. Tantawi
  • Publication number: 20210167475
    Abstract: A non-reciprocal microwave network is provided that includes an in-line ferromagnetic element [1010] with adjoining polarizing adapters [1002, 1004, 1006, 1008] to achieve directivity via a multi-mode interaction at or near the ferrite to act as new class of 4-port circulator or 2-port isolator, with standard waveguide inputs for assembly in larger networks.
    Type: Application
    Filed: February 14, 2019
    Publication date: June 3, 2021
    Inventors: Matthew A. Franzi, Sami G. Tantawi
  • Publication number: 20210060358
    Abstract: A hadron therapy system that provides 3D scanning and rapid delivery of a high dose. Such systems can include a hadron source and accelerator with an RF energy modulator and an RF deflector that operate in combination to provide 3D scanning of a targeted tissue. The systems can include a permanent magnet quadrupole for magnification of the beam. The systems can include high energy hadron sources that utilize a multi-cell, multi-klystron design that achieves scanning of high energy hadron beams, for example a fixed energy of 200 MeV protons. Such systems can provide full irradiation of a liter scale tumor within one second or less.
    Type: Application
    Filed: August 28, 2020
    Publication date: March 4, 2021
    Applicant: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Sami G. Tantawi, Emilio Nanni, Zenghai Li, Cecile Limborg-Deprey
  • Patent number: 10172228
    Abstract: An apparatus for generating high frequency electromagnetic radiation includes a whispering gallery mode resonator, coupled to an output waveguide through a coupling aperture. The resonator has a guiding surface, and supports a whispering gallery electromagnetic eigenmode. An electron source is configured to generate a velocity vector-modulated electron beam, where each electron in the velocity vector-modulated electron beam travels substantially perpendicular to the guiding surface, while interacting with the whispering gallery electromagnetic eigenmode in the whispering gallery mode resonator, generating high frequency electromagnetic radiation in the output waveguide.
    Type: Grant
    Filed: August 11, 2017
    Date of Patent: January 1, 2019
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Sami G. Tantawi, Filippos Toufexis, Michael V. Fazio, Valery A. Dolgashev
  • Publication number: 20170367171
    Abstract: An apparatus for generating high frequency electromagnetic radiation includes a whispering gallery mode resonator, coupled to an output waveguide through a coupling aperture. The resonator has a guiding surface, and supports a whispering gallery electromagnetic eigenmode. An electron source is configured to generate a velocity vector-modulated electron beam, where each electron in the velocity vector-modulated electron beam travels substantially perpendicular to the guiding surface, while interacting with the whispering gallery electromagnetic eigenmode in the whispering gallery mode resonator, generating high frequency electromagnetic radiation in the output waveguide.
    Type: Application
    Filed: August 11, 2017
    Publication date: December 21, 2017
    Inventors: Sami G. Tantawi, Filippos Toufexis, Michael V. Fazio, Valery A. Dolgashev
  • Publication number: 20170325326
    Abstract: An apparatus for generating high frequency electromagnetic radiation includes a whispering gallery mode resonator, coupled to an output waveguide through a coupling aperture. The resonator has a guiding surface, and supports a whispering gallery electromagnetic eigenmode. An electron source is configured to generate a velocity vector-modulated electron beam, where each electron in the velocity vector-modulated electron beam travels substantially perpendicular to the guiding surface, while interacting with the whispering gallery electromagnetic eigenmode in the whispering gallery mode resonator, generating high frequency electromagnetic radiation in the output waveguide.
    Type: Application
    Filed: May 5, 2017
    Publication date: November 9, 2017
    Inventors: Sami G. Tantawi, Filippos Toufexis, Michael V. Fazio, Valery A. Dolgashev
  • Patent number: 9640851
    Abstract: High power RF phase-directed power combiners include magic H hybrid and/or superhybrid circuits oriented in orthogonal H-planes and connected using E-plane bends and/or twists to produce compact 3D waveguide circuits, including 8×8 and 16×16 combiners. Using phase control at the input ports, RF power can be directed to a single output port, enabling fast switching between output ports for applications such as multi-angle radiation therapy.
    Type: Grant
    Filed: May 26, 2015
    Date of Patent: May 2, 2017
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Christopher D. Nantista, Valery A. Dolgashev, Sami G. Tantawi
  • Patent number: 9419322
    Abstract: A multi-port waveguide is provided having a rectangular waveguide that includes a Y-shape structure with first top arm having a first rectangular waveguide port, a second top arm with second rectangular waveguide port, and a base arm with a third rectangular waveguide port for supporting a TE10 mode and a TE20 mode, where the end of the third rectangular waveguide port includes rounded edges that are parallel to a z-axis of the waveguide, a circular waveguide having a circular waveguide port for supporting a left hand and a right hand circular polarization TE11 mode and is coupled to a base arm broad wall, and a matching feature disposed on the base arm broad wall opposite of the circular waveguide for terminating the third rectangular waveguide port, where the first rectangular waveguide port, the second rectangular waveguide port and the circular waveguide port are capable of supporting 4-modes of operation.
    Type: Grant
    Filed: March 9, 2015
    Date of Patent: August 16, 2016
    Assignee: The Borad of Trustees of the Leland Stanford Junior University
    Inventor: Sami G. Tantawi
  • Patent number: 9398681
    Abstract: A microwave circuit for a linear accelerator includes multiple monolithic metallic cell plates stacked upon each other so that the beam axis passes vertically through a central acceleration cavity of each plate. Each plate has a directional coupler with coupling arms. A first coupling slot couples the directional coupler to an adjacent directional coupler of an adjacent cell plate, and a second coupling slot couples the directional coupler to the central acceleration cavity. Each directional coupler also has an iris protrusion spaced from corners joining the arms, a convex rounded corner at a first corner joining the arms, and a corner protrusion at a second corner joining the arms.
    Type: Grant
    Filed: March 12, 2014
    Date of Patent: July 19, 2016
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Sami G. Tantawi, Jeffrey Neilson
  • Patent number: 9386682
    Abstract: A microwave circuit for a linear accelerator has multiple metallic cell sections, a pair of distribution waveguide manifolds, and a sequence of feed arms connecting the manifolds to the cell sections. The distribution waveguide manifolds are connected to the cell sections so that alternating pairs of cell sections are connected to opposite distribution waveguide manifolds. The distribution waveguide manifolds have concave modifications of their walls opposite the feed arms, and the feed arms have portions of two distinct widths. In some embodiments, the distribution waveguide manifolds are connected to the cell sections by two different types of junctions adapted to allow two frequency operation.
    Type: Grant
    Filed: July 9, 2015
    Date of Patent: July 5, 2016
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Sami G. Tantawi, Zenghai Li, Philipp Borchard
  • Patent number: 9287598
    Abstract: A high-power microwave RF window is provided that includes a cylindrical waveguide, where the cylindrical waveguide includes a ceramic disk concentrically housed in a central region of the cylindrical waveguide, a first rectangular waveguide, where the first rectangular waveguide is connected by a first elliptical joint to a proximal end of the cylindrical waveguide, and a second rectangular waveguide, where the second rectangular waveguide is connected by a second elliptical joint to a distal end of the cylindrical waveguide.
    Type: Grant
    Filed: May 7, 2014
    Date of Patent: March 15, 2016
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Sami G. Tantawi, Valery A. Dolgashev, Anahid D. Yeremian
  • Publication number: 20160014876
    Abstract: A microwave circuit for a linear accelerator has multiple metallic cell sections, a pair of distribution waveguide manifolds, and a sequence of feed arms connecting the manifolds to the cell sections. The distribution waveguide manifolds are connected to the cell sections so that alternating pairs of cell sections are connected to opposite distribution waveguide manifolds. The distribution waveguide manifolds have concave modifications of their walls opposite the feed arms, and the feed arms have portions of two distinct widths. In some embodiments, the distribution waveguide manifolds are connected to the cell sections by two different types of junctions adapted to allow two frequency operation.
    Type: Application
    Filed: July 9, 2015
    Publication date: January 14, 2016
    Inventors: Sami G. Tantawi, Zenghai Li, Philipp Borchard
  • Publication number: 20150340752
    Abstract: High power RF phase-directed power combiners include magic H hybrid and/or superhybrid circuits oriented in orthogonal H-planes and connected using E-plane bends and/or twists to produce compact 3D waveguide circuits, including 8×8 and 16×16 combiners. Using phase control at the input ports, RF power can be directed to a single output port, enabling fast switching between output ports for applications such as multi-angle radiation therapy.
    Type: Application
    Filed: May 26, 2015
    Publication date: November 26, 2015
    Inventors: Christopher D. Nantista, Valery A. Dolgashev, Sami G. Tantawi
  • Publication number: 20150194720
    Abstract: A multi-port waveguide is provided having a rectangular waveguide that includes a Y-shape structure with first top arm having a first rectangular waveguide port, a second top arm with second rectangular waveguide port, and a base arm with a third rectangular waveguide port for supporting a TE10 mode and a TE20 mode, where the end of the third rectangular waveguide port includes rounded edges that are parallel to a z-axis of the waveguide, a circular waveguide having a circular waveguide port for supporting a left hand and a right hand circular polarization TE11 mode and is coupled to a base arm broad wall, and a matching feature disposed on the base arm broad wall opposite of the circular waveguide for terminating the third rectangular waveguide port, where the first rectangular waveguide port, the second rectangular waveguide port and the circular waveguide port are capable of supporting 4-modes of operation.
    Type: Application
    Filed: March 9, 2015
    Publication date: July 9, 2015
    Inventor: Sami G. Tantawi
  • Publication number: 20140333395
    Abstract: A high-power microwave RF window is provided that includes a cylindrical waveguide, where the cylindrical waveguide includes a ceramic disk concentrically housed in a central region of the cylindrical waveguide, a first rectangular waveguide, where the first rectangular waveguide is connected by a first elliptical joint to a proximal end of the cylindrical waveguide, and a second rectangular waveguide, where the second rectangular waveguide is connected by a second elliptical joint to a distal end of the cylindrical waveguide.
    Type: Application
    Filed: May 7, 2014
    Publication date: November 13, 2014
    Inventors: Sami G. Tantawi, Valery A. Dolgashev, Anahid D. Yeremian
  • Publication number: 20140191654
    Abstract: A microwave circuit for a linear accelerator includes multiple monolithic metallic cell plates stacked upon each other so that the beam axis passes vertically through a central acceleration cavity of each plate. Each plate has a directional coupler with coupling arms. A first coupling slot couples the directional coupler to an adjacent directional coupler of an adjacent cell plate, and a second coupling slot couples the directional coupler to the central acceleration cavity. Each directional coupler also has an iris protrusion spaced from corners joining the arms, a convex rounded corner at a first corner joining the arms, and a corner protrusion at a second corner joining the arms.
    Type: Application
    Filed: March 12, 2014
    Publication date: July 10, 2014
    Inventors: Sami G. Tantawi, Jeffrey Neilson
  • Patent number: 5801598
    Abstract: A compact high-power RF load comprises a series of very low Q resonators, or chokes ?16!, in a circular waveguide ?10!. The sequence of chokes absorb the RF power gradually in a short distance while keeping the bandwidth relatively wide. A polarizer ?12! at the input end of the load is provided to convert incoming TE.sub.10 mode signals to circularly polarized TE.sub.11 mode signals. Because the load operates in the circularly polarized mode, the energy is uniformly and efficiently absorbed and the load is more compact than a rectangular load. Using these techniques, a load having a bandwidth of 500 MHz can be produced with an average power dissipation level of 1.5 kW at X-band, and a peak power dissipation of 100 MW. The load can be made from common lossy materials, such as stainless steel, and is less than 15 cm in length. These techniques can also produce loads for use as an alternative to ordinary waveguide loads in small and medium RF accelerators, in radar systems, and in other microwave applications.
    Type: Grant
    Filed: May 1, 1997
    Date of Patent: September 1, 1998
    Assignee: Stanford University
    Inventors: Sami G. Tantawi, Arnold E. Vlieks
  • Patent number: 5796314
    Abstract: A high-power RF switching device employs a semiconductor wafer positioned in the third port of a three-port RF device. A controllable source of directed energy, such as a suitable laser or electron beam, is aimed at the semiconductor material. When the source is turned on, the energy incident on the wafer induces an electron-hole plasma layer on the wafer, changing the wafer's dielectric constant, turning the third port into a termination for incident RF signals, and. causing all incident RF signals to be reflected from the surface of the wafer. The propagation constant of RF signals through port 3, therefore, can be changed by controlling the beam. By making the RF coupling to the third port as small as necessary, one can reduce the peak electric field on the unexcited silicon surface for any level of input power from port 1, thereby reducing risk of damaging the wafer by RF with high peak power.
    Type: Grant
    Filed: May 1, 1997
    Date of Patent: August 18, 1998
    Assignee: Stanford University
    Inventors: Sami G. Tantawi, Ronald D. Ruth, Max Zolotorev