Sökning: "phased-array"

Visar resultat 6 - 10 av 28 avhandlingar innehållade ordet phased-array.

  1. 6. Phased array calibration and beamforming using signal processing

    Författare :Maria Lanne; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; mutual coupling; calibration; array imperfections; beampattern synthesis; adaptive beamforming; convex optimization.; array signal processing; Array antennas;

    Sammanfattning : Array antennas have a wide range of applications which includesground and airborne radar, weather radar and anti-collision radar.In addition, equally important applications exist forcommunications, both on earth and to satellites in space, as wellas for medical applications such as the detection and treatment oftumors. LÄS MER

  3. 7. Non-destructive measurement of near-surface cracks in railheads : with focus on ultrasonic inspections

    Författare :Rayendra Anandika; Jan Lundberg; Paul Wilcox; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; rail inspection; phased array; ultrasonic testing; eddy current testing; surface cracks; non-destructive testing; NDT; railway; condition monitoring; Drift och underhållsteknik; Operation and Maintenance;

    Sammanfattning : Near-surface cracks in railhead that caused by rolling contact fatigue (RCF) is one of a kind rail defects that degrade rail track quality. Dependent on the trail load, the cracks can reach to severe level quickly. LÄS MER

  4. 8. Design and Performance of Diversity based Wireless Interfaces for Sensor Network Nodes

    Författare :Magnus Jobs; Anders Rydberg; Shi Cheng; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wireless; Sensor; Network; WSN; Antenna; WISENET; Node; Diversity; Phased Array; Conformal; WBAN; Body Area; Engineering Science with specialization in Microwave Technology; Teknisk fysik med inriktning mot mikrovågsteknik;

    Sammanfattning : The main focus of the work presented in this licentiate thesis concerns antenna design, adaptive antenna control and investigation on how the performance of small wireless nodes can be increased by inclusion of multiple antennas. In order to provide an end-user suitable solution for wireless nodes the devices require both small form factor and good performance in order to be competitive on the marked and thus the main part of this thesis focuses on techniques developed to achieve these goals. LÄS MER

  5. 9. Micro- and Millimeter Wave CMOS Beamforming Receivers

    Författare :Andreas Axholt; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; beamforming; CMOS; front-end; microwave; millimeter wave; phase-locked loop; phased-array;

    Sammanfattning : The available bandwidth in wireless communication systems, such as the 802.11 family, is very limited. Together with the ever increasing data traffic, this causes problems. New possibilities are, however, available thanks to wide license-free bandwidth allocated at higher frequencies. LÄS MER

  7. 10. RF Energy Harvesting for Zero-Energy Devices and Reconfigurable Intelligent Surfaces

    Författare :Morteza Tavana; Emil Björnson; Jens Zander; George Alexandropoulos; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electronic waste; energy harvesting; Internet of Things; optimization; phased array; reconfigurable intelligent surfaces; stochastic geometry; wireless power transfer; wireless sensor networks; zero-energy devices.; Elektronikskrot; energiutvinning; sakernas internet; optimering; fasstyrda antenner; omkonfigurerbara intelligenta ytor; stokastisk geometri; trådlös kraftöverföring; trådlösa sensornätverk; nollenergienheter.; Informations- och kommunikationsteknik; Information and Communication Technology;

    Sammanfattning : The growth of Internet of Things (IoT) networks has made battery replacement in IoT devices increasingly challenging. This issue is particularly pronounced in scenarios with a large number of IoT devices, in locations where IoT devices are difficult to access, or when frequent replacement is necessary. LÄS MER