Sökning: "Umer Shah"

Hittade 5 avhandlingar innehållade orden Umer Shah.

  1. 1. Novel RF MEMS Devices Enabled by Three-Dimensional Micromachining

    Författare :Umer Shah; Joachim Oberhammer; Raafat Mansour; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Microelectromechanical systems; MEMS; Radio frequency microelectromechanical systems; RF MEMS; Micromachined transmission line; Micromachining; Tuneable capacitor; Switched capacitor; Coupled-line coupler; Tuneable directional coupler; Intermodulation distortion; MEMS varactor; Two-tone IIP3 measurement; Passive components and circuits; Reliability; Magnetic materials; NiFe multilayer composite; Permeability; Permittivity; Micromachined inductors;

    Sammanfattning : This thesis presents novel radio frequency microelectromechanical (RF MEMS) circuits based on the three-dimensional (3-D) micromachined coplanar transmission lines whose geometry is re-configured by integrated microelectromechanical actuators. Two types of novel RF MEMS devices are proposed. LÄS MER

  3. 2. Silicon micromachined waveguide components for terahertz systems

    Författare :Bernhard Beuerle; Joachim Oberhammer; Umer Shah; Kamal Sarabandi; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; micromachining; waveguide; terahertz; deep reactive ion etching; silicon on insulator; on-wafer characterization; InP; SiGe; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : This thesis presents silicon micromachined waveguide components for sub-terahertz and terahertz (THz) systems fabricated by deep reactive ion etching (DRIE). Historically the main driving force for the development of THz systems has been space-based scientific instruments for astrophysics, planetary and Earth science missions. LÄS MER

  4. 3. Exploiting the Terahertz Spectrum with Silicon Micromachining : Waveguide Components, Systems and Metrology

    Författare :James Campion; Joachim Oberhammer; Umer Shah; Robert M. Weikle II; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Terahertz; Silicon Micromachining; Waveguide; Waveguide System; Metrology; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : The terahertz spectrum (300 GHz - 3 THz) represents the final frontier for modern electronic and optical systems, wherein few low-cost, volume-manufacturable solutions exist. THz frequencies are of great scientific and commercial interest, with applications as diverse as radio astronomy, sensing and imaging and wireless communications. LÄS MER

  5. 4. Submillimeter-Wave Waveguide Frontends by Silicon-on-Insulator Micromachining

    Författare :Adrian Gomez-Torrent; Joachim Oberhammer; Umer Shah; Goutam Chattopadhyay; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; antenna; orthomode transducer; switch; waveguide; radiofrequency; beamforming network; submillimeter-wave; terahertz; silicon micromachining; deep reactive ion etching; silicon on insulator; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : This thesis presents novel radiofrequency (RF) frontend components in the submillimeter-wave (sub-mmW) range implemented by silicon micromachining, or deep reactive ion etching (DRIE). DRIE is rapidly becoming a driving technology for the fabrication of waveguide components and systems when approaching the terahertz (THz) frequency range. LÄS MER

  7. 5. Advanced MEMS Technology for Terahertz Frequencies

    Författare :Zhao Xinghai; Joachim Oberhammer; Umer Shah; Oleksandr Glubokov; Jan Stake; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : With the development of terahertz (THz) technology, a variety of application demands are growing rapidly, such as high-rate communications, THz radars, environmental monitoring, medical imaging, and space exploration. However, the fabrication, integration, and packaging techniques for THz components and systems pose great challenges for a large-scale, cost-effective production. LÄS MER