Sökning: "broadband antennas"

Visar resultat 1 - 5 av 19 avhandlingar innehållade orden broadband antennas.

  1. 1. Predictor Antennas : Enabling channel prediction for fast-moving vehicles in wireless broadband systems

    Författare :Joachim Björsell; Mikael Sternad; Anders Ahlén; Fredrik Tufvesson; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Predictor antenna; Channel prediction; Long-range prediction; Massive MIMO; Spline interpolation; Channel aging; Outdated CSI; Electrical Engineering with specialization in Signal Processing; Elektroteknik med inriktning mot signalbehandling;

    Sammanfattning : Many advanced transmission techniques utilize channel state information (CSI) at the transmitter (CSIT) to improve throughput, spectral efficiency, power efficiency, and other performance metrics. Estimating CSI accurately is important to fully benefit from many of these techniques. LÄS MER

  3. 2. Dielectrically Loaded Quad-ridge Flared Horns for Ultra Wideband Reflector Feed Applications in Radio Astronomy

    Författare :Jonas Flygare; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; dielectric loaded antennas; dielectric materials; reflector antenna feeds; radio astronomy; ultra wideband antennas; quad-ridge flared horn qrfh ; radio receivers; horn antennas; broadband antennas; aperture antennas.;

    Sammanfattning : Reflector-based radio telescopes are used as tools for observations in both radio astronomy and space geodesy. To observe the weak sources in space, highly sensitive receivers, fronted by optimized reflector feeds, are therefore needed. LÄS MER

  4. 3. Characterization of artificially soft surfaces and their applications in antenna design

    Författare :Zhinong Ying; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; dipole antenna; UTD; GPS; broadband antennas; circular polarization; feed; moment method; soft and hard surfaces; surface impeddance; corrugated horn; antennas; multipath effect; microstrip antenna; magnetic coating; spiral antenna; corrugated surface; dielectric loaded surface; ground plane; slot antenna; monopole antenna; helical antenna; choke-ring;

    Sammanfattning : .... LÄS MER

  5. 4. Integrated Antenna Solutions for Wireless Sensor and Millimeter-Wave Systems

    Författare :Shi Cheng; Anders Rydberg; Paul Hallbjörner; Zhining Chen; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; harmonic radar HR ; liquid alloy; millimeter-wave; micromachining; phase shifters; planar inverted cone antennas PICA ; printed circuit boards PCB ; quasi-Yagi antennas; radio frequency microelectromechanical system RF MEMS ; stretchable antennas; substrate integrate waveguides SIW ; T-matched dipole antennas; tapered slot antennas; traveling wave array antennas; ultrawideband UWB ; wireless sensor networks.; Electrical engineering; Elektroteknik; Elektronik; Electronics;

    Sammanfattning : This thesis presents various integrated antenna solutions for different types of systems and applications, e.g. wireless sensors, broadband handsets, advanced base stations, MEMS-based reconfigurable front-ends, automotive anti-collision radars, and large area electronics. LÄS MER

  7. 5. A comprehensive study of resistor-loaded planar dipole antennas for ground penetrating radar applications

    Författare :Disala Uduwawala; Martin Norgren; Olav Breinbjerg; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ground penetrating radar; buried object detection; dipole antennas; FDTD methods; broadband properties; baluns; simulation; optimal design; lossy media; dispersive media; clutter.; Electrical engineering; Elektroteknik;

    Sammanfattning : Ground penetrating radar (GPR) systems are increasingly being used for the detection and location of buried objects within the upper regions of the earth’s surface. The antenna is the most critical component of such a system. LÄS MER