Sökning: "radio frequency waves"

Visar resultat 26 - 30 av 35 avhandlingar innehållade orden radio frequency waves.

  1. 26. Ultrasound Communication through Thin Plates: Understanding the Channel

    Författare :Asra Ashraf; Jaap van de Beek; Johan E. Carlson; Magnus Sandell; Luleå tekniska universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Signalbehandling; Signal Processing;

    Sammanfattning : Ultrasound, composed of sound waves with frequencies above the human audible range, has become widely used in various technological fields for digital communications. In the past, acoustic and ultrasonic waves were employed in military and commercial un-derwater wireless communication systems due to their superior performance compared to electromagnetic waves. LÄS MER

  3. 27. Micro- and Millimeter Wave CMOS Beamforming Receivers

    Författare :Andreas Axholt; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; beamforming; CMOS; front-end; microwave; millimeter wave; phase-locked loop; phased-array;

    Sammanfattning : The available bandwidth in wireless communication systems, such as the 802.11 family, is very limited. Together with the ever increasing data traffic, this causes problems. New possibilities are, however, available thanks to wide license-free bandwidth allocated at higher frequencies. LÄS MER

  4. 28. Adaptive Programming of RFID Inlays in the Reactive Near Field

    Författare :Markus Frank; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; DTLL; RFID; UHF; RNF; Phase compensation; Phase shifting; Source Impedance Shift; Balun; FOM;

    Sammanfattning : Radio frequency identification (RFID) offers a vast variety of options to improve the functionality and efficiency in the automated data collection (ADC) industry and Internet of Things (IoT). In the inventory process of RFID with passive data carriers, a population of battery less tags is located in the working range of an interrogator system. LÄS MER

  5. 29. Development and Construction of a 2.5-MeV Neutron Time-of-Flight Spectrometer Optimized for Rate (TOFOR)

    Författare :Anders Hjalmarsson; Jan Källne; James Drake; Uppsala universitet; []
    Nyckelord :Nuclear physics; Kärnfysik;

    Sammanfattning : A new neutron time-of-flight spectrometer optimized for high count rate (TOFOR) has been developed for the JET research tokamak. TOFOR will measure the energy distribution of neutrons emitted from the d+d → 3He+n fusion reactions in deuterium plasma. LÄS MER

  7. 30. Submillimeter-Wave Waveguide Frontends by Silicon-on-Insulator Micromachining

    Författare :Adrian Gomez-Torrent; Joachim Oberhammer; Umer Shah; Goutam Chattopadhyay; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; antenna; orthomode transducer; switch; waveguide; radiofrequency; beamforming network; submillimeter-wave; terahertz; silicon micromachining; deep reactive ion etching; silicon on insulator; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : This thesis presents novel radiofrequency (RF) frontend components in the submillimeter-wave (sub-mmW) range implemented by silicon micromachining, or deep reactive ion etching (DRIE). DRIE is rapidly becoming a driving technology for the fabrication of waveguide components and systems when approaching the terahertz (THz) frequency range. LÄS MER