Sökning: "radiometer"

Visar resultat 1 - 5 av 40 avhandlingar innehållade ordet radiometer.

  1. 1. Mixers and Multifunctional MMICs for Millimeter-Wave Applications

    Författare :Sten Gunnarsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; G-band; double-balanced Gilbert mixer; sub-harmonically pumped resistive mixer; pHEMT; receiver; image reject mixer; dual-quadrature mixer; balanced resistive mixer; resistive mixer; 220 GHz; high data rate; drain mixer; 53 GHz; single-chip; V-band.; radiometer; mixer; broadband wireless communication; multifunctional; MMIC; GaAs; mHEMT; transmitter; 60 GHz;

    Sammanfattning : This thesis treats the design and characterization of different mixer and multifunctional monolithic microwave integrated circuits (MMICs) in GaAs pHEMT and mHEMT technologies. The MMICs operate at the V (50 – 75 GHz) and G (140 – 220 GHz) bands and several of them demonstrate state-of-the-art performance, level of integration, novel topologies, and/or novel functionality. LÄS MER

  3. 2. Reconfigurable and Wideband Receiver Components for System-on-Chip Millimetre-Wave Radiometer Front-Ends

    Författare :Shakila Bint Reyaz; Robert Malmqvist; Anders Rydberg; Luca Roselli; Uppsala universitet; []
    Nyckelord :Reconfigurable; Wideband; Receivers; Millimetre-Wave; Radiometers; System-on-Chip; Passive Imaging.; Engineering Science with specialization in Microwave Technology; Teknisk fysik med inriktning mot mikrovågsteknik;

    Sammanfattning : This thesis presents solutions and studies related to the design of reconfigurable and wideband receiver circuits for system-on-chip (SoC) radiometer front-ends within the millimetre-wave (mm-wave) range. Whereas many of today’s mm-wave front-ends are bulky and costly due to having discrete RF components, single-chip receiver modules could potentially result in a wider use for emerging applications such as wireless communication, short range radar and passive imaging security sensors if realised with adequate performances and at a lower cost. LÄS MER

  4. 3. Site dependent error sources in geodetic Very-Long-Baseline Interferometry

    Författare :T. Ragne Carlsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; space geodecy; Water Vapor Radiometer WVR ; very-long-baseling interferometry VLBI ; Global Positioning System GPS ; Kalman filtering;

    Sammanfattning : .... LÄS MER

  5. 4. Optical Analysis and Characterisation of the Climate Research Instrument STEAMR

    Författare :Arvid Hammar; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; limb viewing; Monte Carlo; Stratosphere-Troposphere Exchange And climate Monitor Radiometer STEAMR ; quasi optics; THz; antennas; multi-beam; tolerance analysis; submillimeter-wave instruments; radiometers;

    Sammanfattning : A growing interest for making high resolution observations in the upper troposphere and lower stratosphere has motivated the development of the multi-beam satellite-borne instrument Stratosphere-Troposphere Exchange And climate Monitor Radiometer (STEAMR). The measurements made by STEAMR will be used to monitor trace-gases and link the occurence of these to the Earth's climate by accurate modeling of the atmosphere. LÄS MER

  7. 5. Multispectral reflectance measurements and signature analysis

    Författare :Wolter Arnberg; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : The use of aerial photographs and satellite images may be.facilitated by a deeper knowledge of the reflection properties of natural features. This thesis, which includes a concluding essay and three more papers, is a study of two methods of multispectral reflectance measurements. LÄS MER