Sökning: "Ultra High Frequency"

Visar resultat 1 - 5 av 122 avhandlingar innehållade orden Ultra High Frequency.

  1. 1. High frequency electronic packaging and components : characterization, simulation, materials and processing

    Författare :Christian Johansson; Mats Robertsson; Li-Rong Zheng; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Dielectric loss; high frequency electrical characterization; microwave circuits; multilayer thin film technology; ORMOCER®; permittivity; printed diode; sequential build-up; silicone elastomer; Signal processing; Signalbehandling;

    Sammanfattning : Electronic packaging continues to move towards improved performance and lower cost. Requirements of higher performance, reduced size, weight and cost of both high density interconnects and high frequency devices have led to the search for new materials, material combinations, methods, processes and production equipment. LÄS MER

  3. 2. Impact of adjacent dielectrics on the high-frequency performance of graphene field-effect transistors

    Författare :Muhammad Asad; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; high-frequency electronics; Graphene; transit frequency; contact resistance; MOGFETs; drift velocity; field-effect transistors; saturation velocity; maximum frequency of oscillation; diamond;

    Sammanfattning : Transistors operating at high frequencies are the basic building blocks of millimeter wave communication and sensor systems. The high velocity and mobility of carriers in graphene can open ways for development of ultra-fast group IV transistors with similar or even better performance than that achieved with III-V based semiconductors. LÄS MER

  4. 3. Estimation of Forest Biomass and Faraday Rotation using Ultra High Frequency Synthetic Aperture Radar

    Författare :Gustaf Sandberg; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; Forest Biomass; Ultra High Frequency; Faraday Rotation; Synthetic Aperture Radar;

    Sammanfattning : Synthetic Aperture Radar (SAR) data in the Ultra High Frequency (UHF; 300 MHz – 3 GHz)) band have been shown to be strongly dependent of forest biomass, which is a poorly estimated variable in the global carbon cycle. In this thesis UHF-band SAR data from the fairly flat hemiboreal test site Remningstorp in southern Sweden were analysed. LÄS MER

  5. 4. Ultra-Low Power InAs/AlSb HEMTs for Cryogenic Low-Noise Applications

    Författare :Giuseppe Moschetti; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; low noise; InAs AlSb; metamorphic; low power; high frequency; high electron mobility transistor HEMT ; cryogenic; ion implantation;

    Sammanfattning : The InAs/AlSb high electron mobility transistor (HEMT) is an emerging microwave device technology for ultra-low power and low noise applications. Due to the low bandgap (0. LÄS MER

  7. 5. Ultra-Wideband Time Domain Measurement Systems for Microwave Tomography

    Författare :Xuezhi Zeng; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Time DomainMeasurement; Ultra-Wideband; EquivalentTime Sampling; Real Time Sampling; Microwave Tomography; Measurement Error; Frequency Domain Measurement;

    Sammanfattning : As a potential imaging modality for biomedical applications, microwave tomography has attracted a lot of interests in recent years. With microwave tomography, microwave signals are transmitted into the biological tissues and the scattered fields are recorded. LÄS MER