Sökning: "Wideband radar"

Visar resultat 21 - 25 av 25 avhandlingar innehållade orden Wideband radar.

  1. 21. Development and evaluation of SAR algorithms for image formation and speed estimation in wideband SAR

    Författare :Thomas Sjögren; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Remote sensing and surveillance are the main application areas for radar in general and synthetic aperture (SAR) radar in particular. Since the first radar system built by Hülsmeyer in 1904, radar has developed so that it is now able to create images from a large distance. LÄS MER

  3. 22. 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

  4. 23. On Finding Spectrum Opportunities in Cognitive Radios : Spectrum Sensing and Geo-locations Database

    Författare :Mohamed Hamid; Ben Slimane; Niclas Björsell; Muhammad Imadua Rahman; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; COgnitive Radio; Dynamic Spectrum Access; Spectrum Opportunity; Spectrum Sensing; GEo-locations database;

    Sammanfattning : The spectacular growth in wireless services imposes scarcity in term of the available radio spectrum. A solution to overcome this scarcity is to adopt what so called cognitive radio based on dynamic spectrum access. LÄS MER

  5. 24. Time-Domain Antenna and Scattering Analysis for Micro- and Millimeter-Wave Applications

    Författare :Iman Vakili; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Telecommunications industries are investing tremendously to meet the ever-increasing demands for higher data rates and capacity. In particular to develop standardization for 5G, which is expected around 2020. The existing spectrum for traditional mobile networks is limited to highly occupied bands at microwave frequencies below 6 GHz. LÄS MER

  7. 25. Dispersion Relations in Scattering and Antenna Problems

    Författare :Christian Sohl; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; acoustic and electromagnetic waves; sum rules; scattering and absorption; causality; Herglotz functions;

    Sammanfattning : This dissertation deals with physical bounds on scattering and absorption of acoustic and electromagnetic waves. A general dispersion relation or sum rule for the extinction cross section of such waves is derived from the holomorphic properties of the scattering amplitude in the forward direction. LÄS MER