Sökning: "radomes"

Hittade 5 avhandlingar innehållade ordet radomes.

  1. 1. Stealth radomes

    Författare :Sören Poulsen; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electromagnetic scattering; Dichroic structures; Frequency selective surface; Elektroteknik; FSS; Electrical engineering; Radomes;

    Sammanfattning : This dissertation deals with periodic structures that are used as free-space electromagnetic filters. Two types of periodic structures are treated, namely the so called frequency selective surface (FSS) and the artificial puck plate (APP) structure. LÄS MER

  3. 2. Design and Optimization of Wideband Hat-Fed Reflector Antenna with Radome for Satellite Earth Station

    Författare :Erik G Geterud; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Antenna feeds; satellite earth stations.; optimization; corrugated surfaces; radomes; reflector antennas;

    Sammanfattning : This thesis presents the development of a hat-fed refector antenna with radome to be used as satellite earth station. The antenna with self supported feed is relatively compact, circular symmetric and with low cross polarization. To achieve optimum performance over the satellite Ku-band,covering 10.75-14. LÄS MER

  4. 3. Space Geodesy Techniques: An Experimental and Theoretical Study of Antenna Related Error Sources

    Författare :R. T. Kenneth Jaldehag; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; reflector antennas; signal scattering; very long baseline interferometry VLBI ; signal multipath; space geodesy; GPS error sources; geodetic networks; Global Positioning System GPS ; postglacial rebound; choke-ring antennas;

    Sammanfattning : This thesis presents work associated with antenna related error sources, as well as antenna design, in space geodesy utilizing the techniques of Very-Long-Baseline Interferometry (VLBI) and the Global Positioning System (GPS). Geodetic VLBI uses large radio telescopes, often in global networks observing at least a few times per year. LÄS MER

  5. 4. Thick Frequency Selective Structures

    Författare :Björn Widenberg; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; acoustics; Elektromagnetism; optik; akustik; optics; Electromagnetism; Energy Saving Window; Radome; Finite Elemente Method; Frequency Selective Structure; Mode Matching Technique;

    Sammanfattning : This thesis presents a new method that can handle a general thick Frequency Selective Structure (FSS), that consists of an arbitrary number of aperture layers and dielectric layers. The method is based on the Mode Matching Technique (MMT) and the finite element method (FEM). The thesis consists of a General Introduction and five scientific papers. LÄS MER

  7. 5. Radome Diagnostics: utilizing Source Reconstruction based on Surface Integral Representations

    Författare :Kristin Persson; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nondestructive testing; source reconstruction; diagnostics; radome; phase reconstruction; insertion phase delay IPD ; equivalent surface currents;

    Sammanfattning : In this thesis, an inverse source reconstruction method with great potential in radome diagnostics is presented. A radome is a cover that encloses an antenna in order to protect it from environmental influences. LÄS MER