Sökning: "waveguide"

Visar resultat 6 - 10 av 236 avhandlingar innehållade ordet waveguide.

1. 6. Numerical methods for waveguide modelling

   Författare :Christer Johansson; Björn Engquist; Per Lötstedt; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Waveguide; finite element; hp-adaptivity; helmholtz; maxwell; Numerical analysis; Numerisk analys;

   Sammanfattning : Waveguides are used to transmit electromagnetic signals. Their geometry is typically long and slender. This particular shape can be used in the design of efficient computational methods. Only special modes are transmitted and eigenvalue and eigenvector analysis becomes important. LÄS MER

3. 7. Cylindrical Waveguide Slot Antenna Analysis

   Författare :Johan Wettergren; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; basis function; mutual admittance; cylinder; MPIE; slot; integral equation; waveguide; antenna; mutual coupling; moment method; EFIE;

   Sammanfattning : Waveguide slot antennas with longitudinal and transverse slots are analyzed using a rigorous method. The antennas are divided into regions, which are analyzed separately and matched by a moment method procedure. At the apertures between the regions, the electric fields are expanded in trigonometric basis functions. LÄS MER

4. 8. Analysis of slotted waveguide antennas

   Författare :Lars Manholm; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; coupling junction; slot antenna; compound slot; mutual coupling; wraparound slot; waveguide slot; coupling slot; mutual admittance; edge slot; waveguide junction; moment method;

   Sammanfattning : .... LÄS MER

5. 9. On millimeter and submillimeter wave focal plane arrays implemented with MEMS waveguide switches

   Författare :Henrik Frid; Joachim Oberhammer; Vessen Vassilev; Mikro- och nanosystemteknik KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Extended Hemispherical Lens; Beam Steering; Focal Plane Array FPA ; Ray-Tracing; RF MEMS; waveguide switch; micromachined waveguide; submillimeter-wave; rectangular waveguide; terahertz; lenses; antenna theory; silicon; Electrical Engineering; Elektro- och systemteknik;

   Sammanfattning : This thesis presents research towards enabling micromachined millimeter and submillimeter wave focal plane arrays (FPAs). The FPAs operate under the following principle: a switch network consisting of microelectromechanical (MEMS) switches, integrated with micromachined waveguides, is used to feed an array of antenna elements, located in the focal plane of a high-gain quasi-optical system. LÄS MER

7. 10. Polymer-Based Micromachining for Scalable and Cost-Effective Fabrication of Gap Waveguide Devices Beyond 100 GHz

   Författare :Sadia Farjana; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Dry film photoresist; Terahertz frequency; Injection molding; MEMS; mmWave; Gap waveguide; Antenna; Waveguide; Polymer microfabrication;

   Sammanfattning : The terahertz (THz) frequency bands have gained attention over the past few years due to the growing number of applications in fields like communication, healthcare, imaging, and spectroscopy. Above 100 GHz transmission line losses become dominating, and waveguides are typically used for transmission. LÄS MER