Sökning: "noise matching"

Visar resultat 1 - 5 av 80 avhandlingar innehållade orden noise matching.

  1. 1. Radio Frequency Systems for NMR Imaging: Coil Development and Studies of Non-Thermal Biological Effects

    Författare :Lars Malmgren; Lunds universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; anechoic chamber; TEM transmission cells; FDTD; circularly polarized electromagnetic fields; reduced coupling; noise matching; matching networks; low noise amplifiers; upper thoracic spine; surface coils; Nuclear magnetic resonance; magnetic resonance imaging; non-thermal biological effects; blood-brain barrier; Electronics; Elektronik;

    Sammanfattning : This thesis concerns both design and optimization of NMR imaging systems and studies on non-thermal biological effects of electromagnetic fields. These two research fields are linked together by the fact that humans are subject to static and pulsed magnetic fields as well as to magnetic radio frequency fields (RF) during an NMR imaging investigation. LÄS MER

  3. 2. Development of Cryogenic Low Noise 4-8 GHz HEMT Amplifier and its Advanced Characterization

    Författare :Erik Sundin; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; shot-noise; low noise amplifier; cryogenic amplifier; sis; noise measurement; HEMT;

    Sammanfattning : In most radio astronomy instrumentation, cryogenic low noise amplifiers (LNA) are used as intermediate frequency (IF) amplifiers. The system noise temperature is among the most important parameters of a receiver and requires state of the art components. LÄS MER

  4. 3. Methods for Visually Guided Robotic Systems : Matching, Tracking and Servoing

    Författare :Fredrik Larsson; Michael Felsberg; Per-Erik Forssén; Josef Bigün; Linköpings universitet; []
    Nyckelord :TECHNOLOGY; TEKNIKVETENSKAP;

    Sammanfattning : This thesis deals with three topics; Bayesian tracking, shape matching and visual servoing. These topics are bound together by the goal of visual control of robotic systems. The work leading to this thesis was conducted within two European projects, COSPAL and DIPLECS, both with the stated goal of developing artificial cognitive systems. LÄS MER

  5. 4. Reconfigurable Impedance Matching Networks for Radio Receivers

    Författare :Peter Sjöblom; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Electrical engineering; Telekommunikationsteknik; Telecommunication engineering; Elektronik; Electronics; reconfigurable matching; switched capacitor; antenna tuning unit; impedance tuning unit; High frequency technology; Elektroteknik; microwaves; Högfrekvensteknik; mikrovågor;

    Sammanfattning : Mobile phones become smaller but include more advanced functions for every new generation. This paradox is possible since reduced transistor size and increased integration of digital building blocks free space for new functions. LÄS MER

  7. 5. Acoustic Noise and Echo Cancelling : Microphone Array Methods and Applications

    Författare :Mattias Dahl; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : This Licentiate thesis is divided into three parts corresponding to three different papers. There is one research report, one conference paper and one submitted journal paper. All three parts deal with acoustic echo and/or noise cancelling problems when using adaptive microphone arrays. LÄS MER