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).
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Patent number: 11817612Abstract: 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: GrantFiled: November 30, 2021Date of Patent: November 14, 2023Assignee: The Board of Trustees of the Leland Stanford Junior UniversityInventors: Matthew A. Franzi, Sami G. Tantawi
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Publication number: 20220115758Abstract: 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: ApplicationFiled: November 30, 2021Publication date: April 14, 2022Inventors: Matthew A. Franzi, Sami G. Tantawi
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Patent number: 11258149Abstract: 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: GrantFiled: February 14, 2019Date of Patent: February 22, 2022Assignee: The Board of Trustees of the Leland Stanford Junior UniversityInventors: Matthew A. Franzi, Sami G. Tantawi
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Publication number: 20210167475Abstract: 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: ApplicationFiled: February 14, 2019Publication date: June 3, 2021Inventors: Matthew A. Franzi, Sami G. Tantawi
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Publication number: 20210060358Abstract: 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: ApplicationFiled: August 28, 2020Publication date: March 4, 2021Applicant: The Board of Trustees of the Leland Stanford Junior UniversityInventors: Sami G. Tantawi, Emilio Nanni, Zenghai Li, Cecile Limborg-Deprey
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Patent number: 10172228Abstract: 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: GrantFiled: August 11, 2017Date of Patent: January 1, 2019Assignee: The Board of Trustees of the Leland Stanford Junior UniversityInventors: Sami G. Tantawi, Filippos Toufexis, Michael V. Fazio, Valery A. Dolgashev
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Publication number: 20170367171Abstract: 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: ApplicationFiled: August 11, 2017Publication date: December 21, 2017Inventors: Sami G. Tantawi, Filippos Toufexis, Michael V. Fazio, Valery A. Dolgashev
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Publication number: 20170325326Abstract: 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: ApplicationFiled: May 5, 2017Publication date: November 9, 2017Inventors: Sami G. Tantawi, Filippos Toufexis, Michael V. Fazio, Valery A. Dolgashev
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Patent number: 9640851Abstract: 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: GrantFiled: May 26, 2015Date of Patent: May 2, 2017Assignee: The Board of Trustees of the Leland Stanford Junior UniversityInventors: Christopher D. Nantista, Valery A. Dolgashev, Sami G. Tantawi
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Patent number: 9419322Abstract: 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: GrantFiled: March 9, 2015Date of Patent: August 16, 2016Assignee: The Borad of Trustees of the Leland Stanford Junior UniversityInventor: Sami G. Tantawi
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Patent number: 9398681Abstract: 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: GrantFiled: March 12, 2014Date of Patent: July 19, 2016Assignee: The Board of Trustees of the Leland Stanford Junior UniversityInventors: Sami G. Tantawi, Jeffrey Neilson
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Patent number: 9386682Abstract: 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: GrantFiled: July 9, 2015Date of Patent: July 5, 2016Assignee: The Board of Trustees of the Leland Stanford Junior UniversityInventors: Sami G. Tantawi, Zenghai Li, Philipp Borchard
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Patent number: 9287598Abstract: 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: GrantFiled: May 7, 2014Date of Patent: March 15, 2016Assignee: The Board of Trustees of the Leland Stanford Junior UniversityInventors: Sami G. Tantawi, Valery A. Dolgashev, Anahid D. Yeremian
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Publication number: 20160014876Abstract: 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: ApplicationFiled: July 9, 2015Publication date: January 14, 2016Inventors: Sami G. Tantawi, Zenghai Li, Philipp Borchard
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Publication number: 20150340752Abstract: 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: ApplicationFiled: May 26, 2015Publication date: November 26, 2015Inventors: Christopher D. Nantista, Valery A. Dolgashev, Sami G. Tantawi
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Publication number: 20150194720Abstract: 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: ApplicationFiled: March 9, 2015Publication date: July 9, 2015Inventor: Sami G. Tantawi
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Publication number: 20140333395Abstract: 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: ApplicationFiled: May 7, 2014Publication date: November 13, 2014Inventors: Sami G. Tantawi, Valery A. Dolgashev, Anahid D. Yeremian
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Publication number: 20140191654Abstract: 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: ApplicationFiled: March 12, 2014Publication date: July 10, 2014Inventors: Sami G. Tantawi, Jeffrey Neilson
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Patent number: 5801598Abstract: 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: GrantFiled: May 1, 1997Date of Patent: September 1, 1998Assignee: Stanford UniversityInventors: Sami G. Tantawi, Arnold E. Vlieks
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Patent number: 5796314Abstract: 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: GrantFiled: May 1, 1997Date of Patent: August 18, 1998Assignee: Stanford UniversityInventors: Sami G. Tantawi, Ronald D. Ruth, Max Zolotorev