Search for dissertations about: "uwb antennas"

Showing result 11 - 15 of 17 swedish dissertations containing the words uwb antennas.

  2. 11. Characterization of Small Antennas & Wireless Devices for MIMO Systems in Multipath & Line-of-Sight

    Author : Ahmed Hussain; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; USRP; OTA; SDR; RIMP; TRP; TIS; Reverberation chamber; Rayleigh; MIMO; LOS; LTE; Throughput;

    Abstract : The current thesis investigates over-the-air (OTA) performance characterization of small antennas and wireless terminals in rich isotropic multipath (RIMP) environment, as well as in pure line-of-sight (LOS) environment when taking into account the random positions and orientations of the mobile terminals caused by the realistic user behavior. The latest mobile wireless terminals such as smart phones and tablets can be used in any random orientation thereby making even a received LOS-component appear as a random voltage at the antenna ports over time. READ MORE

  4. 12. Ultra-wideband feed design and characterization for next generation radio telescopes

    Author : Jonas Flygare; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; reflector feed; geodesy; radio astronomy; quad-ridge flared horn; square kilometre array; dielectric loading; spline-defined; decade bandwidth; Ultra-wideband antennas;

    Abstract : Radio telescopes are used as tools for observations in both radio astronomy and geodesy. To observe the weak sources in space, highly sensitive receivers headed by optimized reflector feeds are needed. Wideband and ultra-wideband (UWB) receiver systems enable large continuous frequency bandwidth and reduce the number of receivers that are needed. READ MORE

  5. 13. EM Design for New Ultra Wide Band Technologies: Eleven Feed Baluns, Bowtie Antennas and Gap Waveguides

    Author : Syed Hasan Raza Zaidi; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ultra-wideband; Eleven feed; gap waveguide; baluns; Multiport feeding network; power divider; ring hybrid.; packaging;

    Abstract : UWB (ultra wideband), depending on the application requirement, is usually referred to more than 500 MHz bandwidth for radio/wireless applications. Here in this thesis it is also used to denote extremely wideband antennas and components of several octaves bandwidth, particularly for high frequency applications. READ MORE

  6. 14. Characterization of Small Antennas & Wireless Devices for MIMO Systems in Rich Isotropic Multipath & Random Line-of-Sight

    Author : Ahmed Hussain; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MIMO; Rayleigh; reverberation chamber; random LOS; RIMP; LTE; OTA;

    Abstract : The current thesis is about over-the-air (OTA) performance characterization of wireless terminals in rich isotropic multipath (RIMP) environment as well as in pure line-of-sight (LOS) environment while not ignoring the random positions and orientations of the mobile terminals due to randomness of the user. The latest mobile wireless terminals such as iPhone and iPad can be used in any random position and orientation thereby making the received LOS-component toappear as a random voltage at the antenna ports. READ MORE

  7. 15. Antenna Designs Aiming at the Next Generation of Wireless Communication

    Author : Sadegh Mansouri Moghaddam; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Phased array antenna; MIMO efficiency; CDF; Millimeter-wave; PoD; OTA; Ultra-Wideband UWB antenna; Tightly-Coupled Dipole Array TCDA .; RIMP; Random-LoS; 5G;

    Abstract : Millimeter-wave (mm-wave) frequencies have drawn large attention, specically for the fifth generation (5G) of wireless communication, due to their capability to provide high data-rates. However, design and characterization of the antenna system in wireless communication will face new challenges when we move up to higher frequency bands. READ MORE