Sökning: "vågledare"

Visar resultat 1 - 5 av 16 avhandlingar innehållade ordet vågledare.

  1. 1. Physical modelling of acoustic shallow-water communication channels

    Författare :Elin Svensson; Ilkka Karasalo; Finn Jensen; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; underwater acoustics; hydroacoustics; time variability; ray tracing; Gaussian beam summation; sound propagation models; shallow water; waveguides; caustics; underwater communication; undervattensakustik; hydroakustik; tidsvariabilitet; strålgång; gaussisk strålsummation; ljudutbredningsmodeller; grunt vatten; vågledare; kaustikor; undervattenskommunikation; Acoustics; Akustik;

    Sammanfattning : Akustiska kanaler för undervattenskommunikation är flervägskanaler där ljudet reflekteras från havets yta och botten och bryts vid ljudhastighetsförändringar. I grunt vatten är impulssvaret långt jämfört med symbolernas tidslängd i ett utskickat meddelande. LÄS MER

  3. 2. Design and Numerical Modelling of Nanoplasmonic Structures at Near-Infrared for Telecom Applications

    Författare :Seyed Morteza Ebadi; Jonas Örtegren; Max Yan; Magnus Hummelgård; Carl Hägglund; Mittuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Surface plasmon polaritons SPPs ; resonators; photonic integrated circuits PICs ; wavelength filtering devices; MIM waveguides.; ytplasmon-polaritoner SPPs ; resonatorer; fotoniska integrerade kretsar PIC- enheter ; våglängdsfiltreringsenheter; MIM-vågledare.;

    Sammanfattning : Industrial innovation is mostly driven by miniaturization. As a result of remarkable technological advancements in the fields of equipment, materials and production processes, transistor, the fundamental active component in conventional electronics, has shrunk in size. LÄS MER

  4. 3. 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

  5. 4. 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

  7. 5. Tunable Nanomaterials and their Applications for Terahertz Devices : Carbon Nanotubes and Silver Nanowires

    Författare :Serguei Smirnov; Dmitri Lioubtchenko; Joachim Oberhammer; Hartmut Roskos; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : The interest in terahertz (THz) technologies is growing in academia and industry. The design of electronic components at THz frequencies is relevant to application areas such as telecommunication, radar, material spectroscopy, and medical imaging and diagnosis. LÄS MER