Sökning: "dual polarized"

Visar resultat 1 - 5 av 19 avhandlingar innehållade orden dual polarized.

  1. 1. Polarization diversity and array signal processing in base station antennas

    Författare :Björn Lindmark; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; signal correlation; mobile communication; rayleigh fading; wireless communication; multibeam; dual band; dual polarized; multual coupling; infinite arrays; aperture coupled patch; antenna arrays;

    Sammanfattning : .... LÄS MER

  2. 2. Advanced Dual Circularly Polarized Antenna for Automotive Radar Systems

    Författare :Zhaorui Zang; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; radar; Antenna; polarimetric radar.; automotive; gap waveguide; dual circular polarization; low-profile;

    Sammanfattning : Advanced driver assistance systems (ADAS) promise reliable support for collision avoidance and cruise control. The demand for precise target classification and road surface sensing requires a sensor revolution. In this regard, the automotive radar system is highly expected to collect as much information as possible. LÄS MER

  3. 3. Analysis and Design of Base Station Antennas for Mobile Communications

    Författare :Björn Lindmark; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; polarization diversity; dual polarization; adaptive antennas; moment method; genetic algorithm; antenna arrays; radio propagation; channel sounding; aperture coupled patch;

    Sammanfattning : The thesis deals with base station antennas and the environment they work in. Polarization diversity, dual band operation, and adaptive antenna systems are discussed with emphasis on how antennas for these applications should be designed. We compare the polarization diversity performance of different types of dual polarized antenna elements. LÄS MER

  4. 4. Localization effects in ternary nitride semiconductors

    Författare :Vytautas Liuolia; Saulius Marcinkevicius; Toshiharu Saiki; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; AlGaN; InGaN; AlInN; LEDs; near-field microscopy; carrier dynamics; alloy fluctuations; carrier localization; built-in electric field; nonpolar planes; polarized luminescence;

    Sammanfattning : InGaN based blue and near-ultraviolet light emitting diodes and laser diodes have been successfully commercialized for many applications such as general lighting, display backlighting and high density optical storage devices. Despite having a comparably high defect density, these devices are known for their efficient operation, which is attributed to localization in potential fluctuations preventing carriers from reaching the centers of nonradiative recombination. LÄS MER

  5. 5. Advanced Antenna Systems for Fully Polarimetric Radar in Automotive Scenario

    Författare :Zhaorui Zang; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; circular polarization; gap waveguide; Antenna; dual circular polarization; automotive radar; polarimetric radar;

    Sammanfattning : The increasing dependence on Advanced Driver Assistance Systems (ADAS) highlights the critical need for fast target recognition, effective collision avoidance, cruise control, lane assistance, etc. This necessitates a significant advancement in sensor technology, particularly for accurate target classification and road surface sensing. LÄS MER