Sökning: "GHz"

Visar resultat 1 - 5 av 444 avhandlingar innehållade ordet GHz.

1. 1. Millimeter and Sub-Millimeter Wave Integrated Active Frequency Down-Converters

   Författare :Yu Yan; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; 145 GHz; self-oscillating mixer; mixer; conversion gain; millimeter wave; radar; mHEMT; noise figure; monolithic; sub-millimeter wave; InP; THz; resistive mixer; Gilbert mixer; DHBT; SiGe; 340 GHz; 220 GHz; FMCW; transconductance mixer; BiCMOS; transceiver; harmonic; GaAs;

   Sammanfattning : In recent years, the increasing amount of data transmission, the need for automotiveradars, and standoff imaging for security applications are the main factors that accelerateresearch in the millimeter and sub-millimeter wave frequency ranges. The semiconductorindustries have continuously developed their processes, which have opened upopportunities for manufacturing monolithically integrated circuits up to a few hundredGHz, based on transistor technologies. LÄS MER

3. 2. 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

4. 3. Microsystem technology for microwave applications at frequencies above 100 GHz

   Författare :Sofia Rahiminejad; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Transitions; GHz; High frequency; RF; MEMS; Gap waveguides; Waveguide;

   Sammanfattning : The rapid development of wireless technology today shows an increasing need forelectromagnetic components operating at even higher frequencies. Higher frequencies offer wider bandwidth, higher spatial resolution and are needed for technologies such as automotive car radars, wireless media communication and body scanners. LÄS MER

5. 4. 60 GHz Wireless Propagation Channels: Characterization, Modeling and Evaluation

   Författare :Carl Gustafson; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; 60 GHz; mm-wave; IEEE 802.11ad; IEEE802.15.3c; Channel measurements; Channel modeling; propagation; MIMO; Beamforming; Spatial Multiplexing;

   Sammanfattning : To be able to connect wirelessly to the internet is nowadays a part of everyday life and the number of wireless devices accessing wireless networks worldwide are increasing rapidly. However, with the increasing number of wireless devices and applications and the amount available bandwidth, spectrum shortage is an issue. LÄS MER

7. 5. Micromachined Gap Waveguide Devices

   Författare :Sofia Rahiminejad; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MEMS; Gap waveguides; RF; High frequency; GHz; Waveguide;

   Sammanfattning : Gap waveguide technology is a new technology that is well suited for millimeter and submillimeter applications. Compared to conventional rectangular waveguides, this technology does not need any solid conductive walls to confine the wave by utilizing metamaterial surfaces such as "bed of nails" that creates an artificial magnetic conductive surface (AMC). LÄS MER