Patents by Inventor Xubai Zhang

Xubai Zhang 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: 6960546
    Abstract: Dielectric composite materials including an electronically tunable dielectric phase and a calcium and oxygen-containing compound are disclosed. The tunable phase may comprise a material such as barium strontium titanate. The calcium/oxygen compound may comprise CaO or a transition metal-containing compound such as Ca2Nb2O7 or CaTiO3. The material may also include a rare earth oxide dopant such as CeO2. The materials resist dielectric breakdown and possess improved combinations of electronic properties. The materials may be tailored for specific applications.
    Type: Grant
    Filed: September 27, 2002
    Date of Patent: November 1, 2005
    Assignee: Paratek Microwave, Inc.
    Inventors: Christopher Caspers, Elijah Underhill, Xubai Zhang
  • Publication number: 20050176575
    Abstract: The production of low-loss, tunable composite ceramic materials with improved breakdown strengths is disclosed. The composite materials comprise ferroelectric perovskites such as barium strontium titanate or other ferroelectric perovskites combined with other phases such as low-loss silicate materials and/or other low-loss oxides. The composite materials are produced in sheet or tape form by methods such as tape casting. The composite tapes exhibit favorable tunability, low loss and tailorable dielectric properties, and can be used in various microwave devices.
    Type: Application
    Filed: April 13, 2005
    Publication date: August 11, 2005
    Inventors: Luna Chiu, Xubai Zhang, Louise Sengupta
  • Publication number: 20050088255
    Abstract: This invention provides a voltage tunable filter comprising an input connection point, an output connection point, and at least one circuit branch electrically coupled to the input connection point and the output connection point and including a voltage tunable dielectric varactor electrically connected to an inductor. The voltage tunable filter can be one of a low-pass, high-pass, band-pass, or band-stop filter. The varactor can include built-in DC blocking capacitors.
    Type: Application
    Filed: November 1, 2004
    Publication date: April 28, 2005
    Inventors: Louise Sengupta, Steven Stowell, Yongfei Zhu, Somnath Sengupta, Luna Chiu, Xubai Zhang
  • Patent number: 6876279
    Abstract: A tunable dielectric structure includes a first layer of dielectric material, a second layer of dielectric material positioned adjacent to the first layer of dielectric material, with the second layer of dielectric material having a dielectric constant that is less than the dielectric constant of the first layer of dielectric material, and electrodes for applying a controllable voltage across the first dielectric material, thereby controlling a dielectric constant of the first dielectric material, wherein at least one of the electrodes is positioned between the first and second layers of dielectric material. The dielectric materials can be formed in various shapes and assembled in various orientations with respect to each other. The tunable dielectric structure is used in various devices including coaxial cables, cavity antennas, microstrip lines, coplanar lines, and waveguides.
    Type: Grant
    Filed: February 6, 2002
    Date of Patent: April 5, 2005
    Assignee: Paratek Microwave, Inc.
    Inventors: Louise Sengupta, Steven C. Stowell, Yongfei Zhu, Somnath Sengupta, Luna H. Chiu, Xubai Zhang
  • Patent number: 6864840
    Abstract: A phased array antenna includes a plurality of radiating elements, a feed line assembly, a ground plane positioned between the plurality of radiating elements and the feed line assembly, with the ground plane having a plurality of openings positioned between the plurality of radiating elements and the feed line assembly, and a plurality of voltage tunable dielectric phase shifters coupled to the feed line assembly.
    Type: Grant
    Filed: January 30, 2002
    Date of Patent: March 8, 2005
    Assignee: Paratek Microwave, Inc.
    Inventors: Yongfei Zhu, Louise C. Sengupta, Andrey Kozyrev, Xubai Zhang
  • Patent number: 6794960
    Abstract: A tunable dielectric structure includes a first layer of dielectric material, a second layer of dielectric material positioned adjacent to the first layer of dielectric material, with the second layer of dielectric material having a dielectric constant that is less than the dielectric constant of the first layer of dielectric material, and electrodes for applying a controllable voltage across the first dielectric material, thereby controlling a dielectric constant of the first dielectric material, wherein at least one of the electrodes is positioned between the first and second layers of dielectric material. The dielectric materials can be formed in various shapes and assembled in various orientations with respect to each other. The tunable dielectric structure is used in various devices including coaxial cables, cavity antennas, microstrip lines, coplanar lines, and waveguides.
    Type: Grant
    Filed: February 6, 2002
    Date of Patent: September 21, 2004
    Assignee: Paratek Microwave, Inc.
    Inventors: Luna H. Chiu, Yongfei Zhu, Xubai Zhang, Steven C. Stowell, Andrey Kozyrev, Somnath Sengupta, Louise Sengupta
  • Patent number: 6774077
    Abstract: Electronically tunable dielectric materials having favorable properties are disclosed. The electronically tunable materials include an electronically tunable dielectric phase such as barium strontium titanate in combination with at least two additional metal oxide phases. The additional metal oxide phases may include, for example, oxides of Mg, Si, Ca, Zr, Ti and Al. The electronically tunable materials may be provided in bulk, thin film and thick film forms for use in devices such as phased array antennas, tunable filters and the like. The materials are useful in many applications, including the area of radio frequency engineering and design.
    Type: Grant
    Filed: January 24, 2001
    Date of Patent: August 10, 2004
    Assignee: Paratek Microwave, Inc.
    Inventors: Louise C. Sengupta, Xubai Zhang, Luna H. Chiu
  • Publication number: 20040089985
    Abstract: Electronically tunable dielectric materials having favorable properties are disclosed. The electronically tunable materials include an electronically tunable dielectric phase such as barium strontium titanate in combination with at least two additional metal oxide phases. The additional metal oxide phases may include, for example, oxides of Mg, Si, Ca, Zr, Ti and Al. The electronically tunable materials may be provided in bulk, thin film and thick film forms for use in devices such as phased array antennas, tunable filters and the like. The materials are useful in many applications, including the area of radio frequency engineering and design.
    Type: Application
    Filed: October 16, 2003
    Publication date: May 13, 2004
    Inventors: Louise C. Sengupta, Xubai Zhang, Luna H. Chiu
  • Publication number: 20040063566
    Abstract: Dielectric composite materials including an electronically tunable dielectric phase and a calcium and oxygen-containing compound are disclosed. The tunable phase may comprise a material such as barium strontium titanate. The calcium/oxygen compound may comprise CaO or a transition metal-containing compound such as Ca2Nb2O7 or CaTiO3. The material may also include a rare earth oxide dopant such as CeO2. The materials resist dielectric breakdown and possess improved combinations of electronic properties. The materials may be tailored for specific applications.
    Type: Application
    Filed: September 27, 2002
    Publication date: April 1, 2004
    Inventors: Christopher Caspers, Elijah Underhill, Xubai Zhang
  • Patent number: 6686814
    Abstract: A voltage tunable dielectric varactor includes a substrate having a low dielectric constant and having generally planar surface, a tunable ferroelectric layer positioned on the generally planar surface of the substrate, and first and second electrodes positioned on a surface of the tunable ferroelectric layer opposite the generally planar surface of the substrate. The first and second electrodes are separated to form a gap therebetween. The varactor includes an input for receiving a radio frequency signal and an output for delivering the radio frequency signal. A bias voltage applied to the electrodes changes the capacitance of the varactor between the input and output thereof. Phase shifters and filters that include the varactor are also described.
    Type: Grant
    Filed: August 19, 2002
    Date of Patent: February 3, 2004
    Assignee: Paratek Microwave, Inc.
    Inventors: Luna H. Chiu, Yongfei Zhu, Xubai Zhang, Steven C. Stowell, Andrey Kozyrev, Somnath Sengupta, Louise Sengupta
  • Patent number: 6683516
    Abstract: A tunable dielectric structure includes a first layer of dielectric material, a second layer of dielectric material positioned adjacent to the first layer of dielectric material, with the second layer of dielectric material having a dielectric constant that is less than the dielectric constant of the first layer of dielectric material, and electrodes for applying a controllable voltage across the first dielectric material, thereby controlling a dielectric constant of the first dielectric material, wherein at least one of the electrodes is positioned between the first and second layers of dielectric material. The dielectric materials can be formed in various shapes and assembled in various orientations with respect to each other. The tunable dielectric structure is used in various devices including coaxial cables, cavity antennas, microstrip lines, coplanar lines, and waveguides.
    Type: Grant
    Filed: February 6, 2002
    Date of Patent: January 27, 2004
    Assignee: Paratek Microwave, Inc.
    Inventors: Luna H. Chiu, Yongfei Zhu, Xubai Zhang, Steven C. Stowell, Andrey Kozyrev, Somnath Sengupta, Louise Sengupta
  • Patent number: 6683517
    Abstract: A tunable dielectric structure includes a first layer of dielectric material, a second layer of dielectric material positioned adjacent to the first layer of dielectric material, with the second layer of dielectric material having a dielectric constant that is less than the dielectric constant of the first layer of dielectric material, and electrodes for applying a controllable voltage across the first dielectric material, thereby controlling a dielectric constant of the first dielectric material, wherein at least one of the electrodes is positioned between the first and second layers of dielectric material. The dielectric materials can be formed in various shapes and assembled in various orientations with respect to each other. The tunable dielectric structure is used in various devices including coaxial cables, cavity antennas, microstrip lines, coplanar lines, and waveguides.
    Type: Grant
    Filed: February 6, 2002
    Date of Patent: January 27, 2004
    Assignee: Paratek Microwave, Inc.
    Inventors: Luna H. Chiu, Yongfei Zhu, Xubai Zhang, Steven C. Stowell, Andrey Kozyrev, Somnath Sengupta, Louise Sengupta
  • Publication number: 20030119656
    Abstract: The production of low-loss, tunable composite ceramic materials with improved breakdown strengths is disclosed. The composite materials comprise ferroelectric perovskites such as barium strontium titanate or other ferroelectric perovskites combined with other phases such as low-loss silicate materials and/or other low-loss oxides. The composite materials are produced in sheet or tape form by methods such as tape casting. The composite tapes exhibit favorable tunability, low loss and tailorable dielectric properties, and can be used in various microwave devices.
    Type: Application
    Filed: November 22, 2002
    Publication date: June 26, 2003
    Applicant: Paratek Microwave, Inc.
    Inventors: Luna H. Chiu, Xubai Zhang, Louise C. Sengupta
  • Patent number: 6531936
    Abstract: A voltage tunable dielectric varactor includes a substrate having a low dielectric constant and having generally planar surface, a tunable ferroelectric layer positioned on the generally planar surface of the substrate, and first and second electrodes positioned on a surface of the tunable ferroelectric layer opposite the generally planar surface of the substrate. The first and second electrodes are separated to form a gap therebetween. The varactor includes an input for receiving a radio frequency signal and an output for delivering the radio frequency signal. A bias voltage applied to the electrodes changes the capacitance of the varactor between the input and output thereof. Phase shifters and filters that include the varactor are also described.
    Type: Grant
    Filed: October 15, 1999
    Date of Patent: March 11, 2003
    Assignee: Paratek Microwave, Inc.
    Inventors: Luna H. Chiu, Yongfei Zhu, Xubai Zhang, Steven C. Stowell, Andrey Kozyrev, Somnath Sengupta, Louise Sengupta
  • Patent number: 6514895
    Abstract: The present invention relates to electronically tunable dielectric materials which have favorable properties for many applications, including the area of radio frequency (RF) engineering and design. The electronically tunable materials include an electronically tunable dielectric phase such as barium strontium titanate in combination with a metal silicate phase such as Mg2SiO4. The electronically tunable materials may be provided in bulk, thin film and thick film forms for use in devices such as phased array antennas, tunable filters and the like.
    Type: Grant
    Filed: June 15, 2000
    Date of Patent: February 4, 2003
    Assignee: Paratek Microwave, Inc.
    Inventors: Luna H. Chiu, Xubai Zhang, Louise Sengupta
  • Publication number: 20020186099
    Abstract: This invention provides a voltage tunable filter comprising an input connection point, an output connection point, and at least one circuit branch electrically coupled to the input connection point and the output connection point and including a voltage tunable dielectric varactor electrically connected to an inductor. The voltage tunable filter can be one of a low-pass, high-pass, band-pass, or band-stop filter. The varactor can include built-in DC blocking capacitors.
    Type: Application
    Filed: December 9, 1999
    Publication date: December 12, 2002
    Inventors: LOUISE C. SENGUPTA, STEVEN C. STOWELL, YONGFEI ZHU, SOMNATH SENGUPTA, LUNA H. CHIU, XUBAI ZHANG
  • Publication number: 20020165080
    Abstract: Electronically tunable dielectric materials having favorable properties are disclosed. The electronically tunable materials include an electronically tunable dielectric phase such as barium strontium titanate in combination with at least two additional metal oxide phases. The additional metal oxide phases may include, for example, oxides of Mg, Si, Ca, Zr, Ti and Al. The electronically tunable materials may be provided in bulk, thin film and thick film forms for use in devices such as phased array antennas, tunable filters and the like. The materials are useful in many applications, including the area of radio frequency engineering and design.
    Type: Application
    Filed: January 24, 2001
    Publication date: November 7, 2002
    Inventors: Louise C. Sengupta, Xubai Zhang, Luna H. Chiu
  • Publication number: 20020126048
    Abstract: A phased array antenna includes a plurality of radiating elements, a feed line assembly, a ground plane positioned between the plurality of radiating elements and the feed line assembly, with the ground plane having a plurality of openings positioned between the plurality of radiating elements and the feed line assembly, and a plurality of voltage tunable dielectric phase shifters coupled to the feed line assembly.
    Type: Application
    Filed: January 30, 2002
    Publication date: September 12, 2002
    Inventors: Yongfei Zhu, Louise C. Sengupta, Andrey Kozyrev, Xubai Zhang
  • Publication number: 20020101309
    Abstract: A tunable dielectric structure includes a first layer of dielectric material, a second layer of dielectric material positioned adjacent to the first layer of dielectric material, with the second layer of dielectric material having a dielectric constant that is less than the dielectric constant of the first layer of dielectric material, and electrodes for applying a controllable voltage across the first dielectric material, thereby controlling a dielectric constant of the first dielectric material, wherein at least one of the electrodes is positioned between the first and second layers of dielectric material. The dielectric materials can be formed in various shapes and assembled in various orientations with respect to each other. The tunable dielectric structure is used in various devices including coaxial cables, cavity antennas, microstrip lines, coplanar lines, and waveguides.
    Type: Application
    Filed: February 6, 2002
    Publication date: August 1, 2002
    Inventors: Luna H. Chiu, Yongfei Zhu, Xubai Zhang, Steven C. Stowell, Andrey Kozyrev, Somnath Sengupta, Louise Sengupta
  • Publication number: 20020097117
    Abstract: A tunable dielectric structure includes a first layer of dielectric material, a second layer of dielectric material positioned adjacent to the first layer of dielectric material, with the second layer of dielectric material having a dielectric constant that is less than the dielectric constant of the first layer of dielectric material, and electrodes for applying a controllable voltage across the first dielectric material, thereby controlling a dielectric constant of the first dielectric material, wherein at least one of the electrodes is positioned between the first and second layers of dielectric material. The dielectric materials can be formed in various shapes and assembled in various orientations with respect to each other. The tunable dielectric structure is used in various devices including coaxial cables, cavity antennas, microstrip lines, coplanar lines, and waveguides.
    Type: Application
    Filed: February 6, 2002
    Publication date: July 25, 2002
    Inventors: Luna H. Chiu, Yongfei Zhu, Xubai Zhang, Steven C. Stowell, Andrey Kozyrev, Somnath Sengupta, Louise C. Sengupta