Search for dissertations about: "DCO"

Showing result 1 - 5 of 7 swedish dissertations containing the word DCO.

  2. 1. Low Noise Oscillator in ADPLL toward Direct-to-RF All-digital Polar Transmitter

    Author : Jian Chen; Li-Rong Zheng; Fredrik Jonsson; Hannu Tenhunen; Georges Gielen; KTH; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; all-digital; digitally-intensive; frequency modualtion; phase modulation; amplitude modulation; polar; transmitter; oscillator; digital controled oscillator; DCO; VCO; voltage controled oscillator; class-C oscillator; class-D PA; ADPLL; phase noise; RF; CMOS.;

    Abstract : In recent years all-digital or digitally-intensive RF transmitters (TX) have attracted great attention in both literature and industry. The motivation is to implement RF circuits in a manner suiting advanced nanometer CMOS processes. To achieve that, information is encoded in the time-domain rather than voltage amplitude. READ MORE

  4. 2. Digital Phase Locked Loops for Radio Frequency Synthesis

    Author : Ahmed Mahmoud; Integrerade elektroniksystem; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; CMOS; PLL; DPLL; VCO; DCO; loop filter; DS modulator; phase noise; spurs; quantization noise; BBPD; TDC; DTC;

    Abstract : The demands for an ever higher data rate and a more varied functionality at minimal cost and power consumption have been the driving force behind most innovations in wireless communication systems. Intensive efforts have been made to develop Radio Frequency (RF) Integrated Circuits (ICs) and systems using low-cost Complementary Metal Oxide Semiconductor (CMOS) processes. READ MORE

  5. 3. Advanced Functional Materials for Intermediate-Temperature Ceramic Fuel Cells

    Author : Zhan Gao; Bill Bergman; Mogens Mogensen; Ceramics; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Abstract : Low to intermediate-temperature solid oxide fuel cell (SOFC, 500 oC-700 oC) based on doped ceria (DCO) electrolyte has attracted much attention during the last decade. However, DCO suffers from electronic conduction caused byreduction of Ce (IV) to Ce (III) at high temperatures and low oxygen partial pressures and has a high grain-boundary resistivity. READ MORE

  6. 4. Novel methods for 3-D semi-automatic mapping of fracture geometry at exposed rock faces

    Author : Quanhong Feng; KTH; []
    Keywords : 3-D laser scanner; close-range photogrammetry; engineering geology; fracture geometry; fracture mapping; rock engineering; rock faces; rock mechanics; three-dimension; total station;

    Abstract : To analyse the influence of fractures on hydraulic andmechanical behaviour of fractured rock masses, it is essentialto characterise fracture geometry at exposed rock faces. Thisthesis describes three semi-automatic methods for measuring andquantifying geometrical parameters of fractures, and aims tooffer a novel approach to the traditional mapping methods. READ MORE

  7. 5. Studies of Interstellar Molecular Gas in the Magellanic Clouds

    Author : Arto Heikkilä; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; abundances-Galaxies; evolution; molecules-Galaxies; Magellanic Clouds-Interstellar medium; molecules-Galaxies; interstellar medium-Galaxies;

    Abstract : Results of observational studies of interstellar molecular gas clouds in the Large Magellanic Cloud (LMC) and the Small Magellanic Cloud (SMC), two nearby metal-poor and dust-poor dwarf galaxies, are presented. Spectral line radiation emitted by interstellar molecules has been used to probe the physical state and the chemical composition of individual molecular clouds. READ MORE