Sökning: "Ultra wideband"

Visar resultat 16 - 20 av 67 avhandlingar innehållade orden Ultra wideband.

1. 16. Evaluation of Sigma-Delta-over-Fiber for High-Speed Wireless Applications

   Författare :Ibrahim Can Sezgin; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; energy harvesting; wireless power transfer; 1-bit communication; distributed-MIMO; Sigma-delta-over-fiber SDoF ; vertical-cavity surface-emitting-laser VCSEL ; radio frequency RF ; wideband; ultra-high speed communication;

   Sammanfattning : Future mobile communication networks aim to increase the communication speed, provide better reliability and improve the coverage. It needs to achieve all of these enhancements, while the number of users are increasing drastically. LÄS MER

3. 17. On the Physical Layer of Ultra-Wideband Systems

   Författare :Matts-Ola Wessman; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : This licentiate thesis consists of two published conference papers, onetechnical report, and an introduction. The focus is on communication at bitrates of 100 Mbps and higher for single-user systems at short range up to 10meters. LÄS MER

4. 18. THz Ultra-wideband Passive Devices: Design, Simulation and Characterization

   Författare :Cristian Daniel López; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Superconducting Transition; Substrateless Finline; Compact waveguide twist; Marchand Baluns.; Broadband Waveguide to Substrate Transition;

   Sammanfattning : The last decades have seen an increasing interest in the THz research field, leading to a substantial improvement in technology and the emergence of new applications. In particular, the research on radio astronomy instrumentation has pushed millimeter and sub-millimeter technology boundaries and redefined state of the art. LÄS MER

5. 19. Impulse Radio UWB for the Internet-of-Things : A Study on UHF/UWB Hybrid Solution

   Författare :Zhuo Zou; Hannu Tenhunen; Tor Sverre Lande; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Ultra-Wideband; impulse radio; IR-UWB; RFID; asymmetric links; UHF UWB hybrid; wireless sensing; energy detection; low power; radio receiver; positioning; Internet-of-Things;

   Sammanfattning : This dissertation investigates Ultra-Wideband (UWB) techniques for the next generation Radio Frequency Identification (RFID) towards the Internet-of-Things (IoT). In particular, an ultra-high frequency (UHF) wireless-powered UWB radio (UHF/UWB hybrid) with asymmetric links is explored from system architecture to circuit implementation. LÄS MER

7. 20. Electron Tunneling and Field-Effect Devices in mm-Wave Circuits

   Författare :Mikael Egard; Fasta tillståndets fysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; negative differential conductance oscillator; resonant tunneling diode; ultra-wideband; impulse radio; Wavelet generator; MOSFET; nanowire; high frequency characterization; Fysicumarkivet A:2012:Egard;

   Sammanfattning : Short high-frequency electromagnetic pulses, also referred to as wavelets, are considered for use in various short-range impulse based ultra-wideband applications, such as communication, imaging, radar, spectroscopy, and localization. This thesis investigates field-effect and tunneling based semiconductor devices and their operation in millimeter-wave (mm-wave) impulse transceivers. LÄS MER