Sökning: "GaN-HEMT"

Visar resultat 11 - 15 av 28 avhandlingar innehållade ordet GaN-HEMT.

1. 11. GaN HEMT Low Noise Amplifiers for Radio Base Station Receivers

   Författare :Pirooz Chehrenegar; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; gallium nitride GaN ; radio base station receiver; cascode; high linearity; robustness.; cascade; high electron mobility transistor HEMT ; low noise; low noise amplifier;

   Sammanfattning : Gallium nitride (GaN) high electron mobility transistor (HEMT) has been introduced as the technology of choice for high power microwave applications due to its material properties including high saturation electron velocity and breakdown field together with excellent thermal conductivity and robustness.It is also a promising candidate for receiver front-ends in the radio base station(RBS) where low noise figure and high linearity are key issues for low noiseamplifier (LNA) design. LÄS MER

3. 12. High-efficiency Power Amplification Techniques for Wireless Transmitters

   Författare :Hossein Mashad Nemati; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; load modulation; LDMOS; supply modulation; GaN HEMT; Power amplifier; wireless communications.; GaAs mHEMT; efficiency;

   Sammanfattning : The low efficiency of existing power amplifiers (PAs) is causing excessive energy consumption in wireless systems. Improving the PA efficiency is therefore of great environmental and economical importance. LÄS MER

4. 13. Characterization and Compensation of Thermal Effects in GaN HEMT Technologies

   Författare :Johan Bremer; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; thermal coupling; thermal effects; thermal resistance; AlGaN GaN; temperature compensation.; electrothermal; characterization;

   Sammanfattning : Further advancements with GaN based technologies relies on the ability to handle the heat flux, which consequently arises from the high power density. Advanced cooling techniques and thermal optimization of the technology are therefore prioritized research areas. LÄS MER

5. 14. Nonlinear Microwave Measurement Architectures for Wideband Device Characterization

   Författare :Sebastian Gustafsson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Nonlinear characterization; wideband; GaN HEMT; oscilloscope; microwave; active load-pull;

   Sammanfattning : The global surge for ubiquitous mobile communication requiring high speed and high capacity cellular networks has resulted in a golden age for the development of wireless technology. Modern cellular standards employ complex modulation formats with wider signal bandwidths to cope with the growing demand. LÄS MER

7. 15. Design, Fabrication and Characterization of GaN HEMTs for Power Switching Applications

   Författare :Björn Hult; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; DCIT; SCE; high voltage; isolation; ‘buffer-free’; gate dielectric; GaN HEMT; passivation; DIBL;

   Sammanfattning : The unique properties of the III-nitride heterostructure, consisting of gallium nitride (GaN), aluminium nitride (AlN) and their ternary compounds (e.g. AlGaN, InAlN), allow for the fabrication of high electron mobility transistors (HEMTs). LÄS MER