Search for dissertations about: "Voltage controlled oscillator design"

Showing result 1 - 5 of 14 swedish dissertations containing the words Voltage controlled oscillator design.

  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. Integrated VCOs in Gallium Arsenide HEMT technologies with a novel varactor structure

    Author : Mattias Ferndahl; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; design; Oscillator; HEMT; pHEMT; MMIC; VCO; varactor; GaAs; mHEMT;

    Abstract : This thesis presents results on metamorphic and pseudomorpic GaAs HEMT based Voltage Controlled Oscillators and a novel high-Q varactor structure, used in the VCOs, together with a straightforward extraction procedure for the varactors.Theory and fundamentals around LC-oscillators with oscillator criteria, phase noise and different topologies are given as background together with VCO phase noise measurement methods and an overview on device flicker noise; its physical origin and measurement. READ MORE

  5. 3. GaN HEMT Low Frequency Noise Characterization for Low Phase Noise Oscillator Design

    Author : Thi Ngoc Do Thanh; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Low frequency noise; flicker noise; phase noise; deposition method.; oscillator; VCO; GaAs pHEMT; MMIC; GaN HEMT; passivation; InGaP HBT;

    Abstract : The thesis presents low frequency noise (LFN) characterization of Gallium Nitride (GaN) High Electron Mobility Transistors (HEMTs) for low phase noise oscillator design. First, GaN HEMT technology is benchmarked versus other transistor technologies, e.g. READ MORE

  6. 4. Low Phase Noise GaN HEMT Oscillator Design based on High-Q resonators

    Author : Mikael Hörberg; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; resonator coupling; reflection oscillator; MMIC; phase noise; cavity resonator; low-frequency noise; GaN HEMT; MEMS;

    Abstract : The thesis considers the design and optimization of oscillators targeting low phase noise, given boundary conditions from the technology. Crucial technology figures are power capability, RF noise figure, low-frequency noise and the quality factor (Q-factor) of the resonator. READ MORE

  7. 5. Modeling and Estimation of Phase Noise in Oscillators with Colored Noise Sources

    Author : M Reza Khanzadi; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Phase Noise Model; Bayesian Cramer-Rao Bound; Voltage-controlled Oscillator; Extended Kalman Filter Smoother; Maximum a Posteriori Estimator; Colored Phase Noise; Oscillator Phase Noise; Phase-Locked Loop; Mean Square Error.;

    Abstract : The continuous increase in demand for higher data rates due to applications with massive number of users motivates the design of faster and more spectrum efficient communication systems. In theory, the current communication systems must be able to operate close to Shannon capacity bounds. READ MORE