Sökning: "millimeter wave"

Visar resultat 1 - 5 av 76 avhandlingar innehållade orden millimeter wave.

  1. 1. Millimeter-wave Networking Fundamental Limits, Scalable Algorithms, and Design Insights

    Detta är en avhandling från KTH Royal Institute of Technology

    Författare :Hossein Shokri-Ghadikolaei; KTH.; KTH.; [2017]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : The current demands for extremely high data rate wireless services and the spectrum scarcity at the sub-6 GHz bands are forcefully motivating the use of the millimeter-wave (mmWave) frequencies. The main characteristics of mmWave communications are severe attenuation, sparse-scattering environment, huge bandwidth, vulnerability to obstacles and antenna misalignment, massive beamforming, and possible noise-limited operation. LÄS MER

  2. 2. Millimeter-Wave Photonics: Signal Sources and Transmission Links

    Detta är en avhandling från KTH Royal Institute of Technology

    Författare :Andreas Wiberg; [2005]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; microwave photonics; mm-wave generation; radio over fiber; photonic frequency multiplication; millimeter-wave photonics; millimeter-waves; millimeter-wave communication system;

    Sammanfattning : With the use of higher and higher frequencies in a number of current and future wireless millimeter-wave applications it is beneficial to use photonics for several reasons. The use of optical fibers is an advantageous way to transport millimeter-waves in terms of loss, mechanical flexibility, weight, and insensitivity to electromagnetic interference. LÄS MER

  3. 3. Millimeter and Sub-Millimeter Wave Integrated Active Frequency Down-Converters

    Detta är en avhandling från KTH Royal Institute of Technology

    Författare :Yu Yan; [2015]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; 145 GHz; self-oscillating mixer; mixer; conversion gain; millimeter wave; radar; mHEMT; noise figure; monolithic; sub-millimeter wave; InP; THz; resistive mixer; Gilbert mixer; DHBT; SiGe; 340 GHz; 220 GHz; FMCW; transconductance mixer; BiCMOS; transceiver; harmonic; GaAs;

    Sammanfattning : In recent years, the increasing amount of data transmission, the need for automotiveradars, and standoff imaging for security applications are the main factors that accelerateresearch in the millimeter and sub-millimeter wave frequency ranges. The semiconductorindustries have continuously developed their processes, which have opened upopportunities for manufacturing monolithically integrated circuits up to a few hundredGHz, based on transistor technologies. LÄS MER

  4. 4. Millimeter-Wave Impulse Radio

    Detta är en avhandling från KTH Royal Institute of Technology

    Författare :Mats Ärlelid; Lund University.; Lunds universitet.; [2012]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Compound semiconductor; resonant tunneling diode; ultra wideband; 60 GHz; on-off keying; transmitter; receiver; and super-regenerative oscillator;

    Sammanfattning : This thesis investigates the opportunity of wireless multi-gigabit per second communication at the millimeter-wave (mmW) frequencies around 60 GHz by using impulse radio and nanoelectronics. Today most wireless communication take place in the microwave region, where several different systems and applications are crowding the narrow-band channels. LÄS MER

  5. 5. Micro- and Millimeter Wave CMOS Beamforming Receivers

    Detta är en avhandling från KTH Royal Institute of Technology

    Författare :Andreas Axholt; Lund University.; Lunds universitet.; Lund University.; Lunds universitet.; [2011]
    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