Search for dissertations about: "beamforming"

Showing result 6 - 10 of 99 swedish dissertations containing the word beamforming.

  2. 6. Direction finding, beamforming and mutual coupling in base station antenna arrays

    Author : Staffan Lundgren; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; mutual coupling; adaptive arrays; direction finding; base station antennas; mobile communications; phase-only nulling; beamforming; dual polarization; butler matrix;

    Abstract : .... READ MORE

  4. 7. Digital Beamforming Focal Plane Arrays for Radio Astronomy and Space-Borne Passive Remote Sensing

    Author : Oleg Iupikov; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; beamforming; spaceborne radiometers; radio telescopes; phased array feeds; reflector antenna feeds; feed-reflector interaction;

    Abstract : Dense Phased Array Feeds (PAFs) for reflector antennas have numerous advantages over traditional cluster feeds of horns in a one-horn-per-beam configuration, especially in RF-imaging applications which require multiple simultaneously formed and closely overlapping beams. However, the accurate analysis and design of such PAF systems represents a challenging problem, both from an EM-modeling and beamforming optimization point of view. READ MORE

  5. 8. Cross-layer Aspects in OFMDA Systems : Feedback, Scheduling and Beamforming

    Author : Patrick Svedman; Björn Ottersten; Ana I. Pérez-Neira; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Telecommunication; Telekommunikation;

    Abstract : This thesis mainly studies the downlink of a wireless multiuser system, where the transmitter has limited knowledge about the communication channels of the users. Key techniques to improve the performance of such systems are, for instance, multiple antennas, multiuser diversity and orthogonal frequency-division multiple access (OFDMA). READ MORE

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

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

    Abstract : 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. READ MORE

  7. 10. Ultrasonic Arrays for Sensing and Beamforming of Lamb Waves

    Author : Marcus Engholm; Tadeusz Stepinski; Paul D. Wilcox; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; imaging; array processing; guided waves; Lamb waves; dispersive waves; multi-modal waves; spatial filtering; mode suppression; resonant ultrasound; transducer design; direction of arrival estimation; adaptive beamforming; Signal processing; Signalbehandling; Electronic measurement and instrumentation; Elektronisk mät- och apparatteknik;

    Abstract : Non-destructive testing (NDT) techniques are critical to ensure integrity and safety of engineered structures. Structural health monitoring (SHM) is considered as the next step in the field enabling continuous monitoring of structures. READ MORE