Sökning: "compact antennas"

Visar resultat 1 - 5 av 38 avhandlingar innehållade orden compact antennas.

  1. 1. Decoupling and Evaluation of Multiple Antenna Systems in Compact MIMO Terminals

    Författare :Hui Li; Sailing He; Cyril Luxey; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Multiple antennas; mutual coupling; compact antennas; frequency reconfigurable antennas; pattern reconfigurable antennas; meta-material antennas; mobile antennas; fractal antennas; collocated antennas; antenna measurement.;

    Sammanfattning : Research on multiple antenna systems has been a hot topic in recent years due to the demands for higher transmission rate and more reliable link in rich scattering environment in wireless communications. Using multiple antennas at both the transmitter side and the receiver side increases the channel capacity without additional frequency spectrum and transmitted power. LÄS MER

  3. 2. Integrated Antennas : Monolithic and Hybrid Approaches

    Författare :Erik Öjefors; Anders Rydberg; Sayan Mukherjee; Duixian Liu; Uppsala universitet; []
    Nyckelord :Electronics; antenna travelling wave arrays; antenna phased arrays; phase shifters; micromachining; silicon; monolithic microwave integrated circuits; dipole antennas; loop antennas; slot antennas; Elektronik;

    Sammanfattning : This thesis considers integration of antennas and active electronics manufactured on the same substrate. The main topic is on-chip antennas for commercial silicon processes, but hybrid integration using printed circuit board technology is also addressed. LÄS MER

  4. 3. Miniaturized Hard Waveguides in Multifunction Array Antennas

    Författare :Malcolm Ng Mou Kehn; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; interlaced arrays; Floquet theorem; reflector antennas; focal plane array; multifunction antennas; miniaturized waveguides; multilayer structures; spectral domain technique; periodic structures; aperture reuse; method of moments; soft and hard surfaces; array antennas;

    Sammanfattning : Recent advances in technologies of wireless communications systems have led to an increasing desire for several antennas performing diverse functions at different frequencies to be integrated into a common radiating aperture. This gives rise to the so-called multifunction antenna, which affords the saving of scarce premium real estate and can alleviate problems arising from excessive antenna protrusions in aspects such as aerodynamics, aesthetics, and stealth capability in military applications. LÄS MER

  5. 4. 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

  7. 5. 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