Sökning: "high power amplifier"

Visar resultat 21 - 25 av 120 avhandlingar innehållade orden high power amplifier.

1. 21. Quantization and Noise-Shaped Coding for High Efficiency Transmitter Architectures

   Författare :Ulf Gustavsson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Software Defined Radio; Quantization; damped Gauss-Newton; Pulse Density Modulation; Noise-Shaped Coding; ΣΔ-Modulators; Power Amplifier;

   Sammanfattning : Three driving parameters in the development of transmitter technologies for wireless communication today is: energy efficiency, flexibility and footprint reduction. This thesis investigates the use of 1-bit oversampled signal representation, mainly as a power efficiency enhancement technique for the transmitter, but also as a path toward reduced footprint and increased flexibility. LÄS MER

3. 22. InP High Electron Mobility Transistors for Cryogenic Low-Noise and Low-Power Amplifiers

   Författare :Eunjung Cha; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; indium channel content; electrical stability.; dc power dissipation; noise temperature; scaling; low-noise amplifier LNA ; InP high-electron mobility transistor InP HEMT ; cryogenic;

   Sammanfattning : The InAlAs/InGaAs/InP high-electron mobility transistor (InP HEMT) is the preferred low-noise device in cryogenic low-noise amplifiers (LNAs) operating at 5-15 K. Such LNAs are utilized in microwave and millimeter-wave detection in radio astronomy. LÄS MER

4. 23. All Digital Polar Transmitter Design for Software Defined Radio : Architecture and Low Power Circuit Implementation

   Författare :Liang Rong; Li-Rong Zheng; Henrik Sjöland; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Switching Power Amplifier; All Digital Polar Transmitter; Lowpass Sigma Delta Modulation; Software Defined Radio; RFID; H-Bridge Architecture; Resonating; Filter Matching Network.; SRA - ICT; SRA - Informations- och kommunikationsteknik;

   Sammanfattning : The evolving wireless communication technology is aiming highdata rate, high mobility, long distance and at the meantime, co-existwith various different standards. This developing trend requires ahighly linear transceiver system and it causes the problem of lowefficiency due to the large crest factor of signals. LÄS MER

5. 24. High Temperature Bipolar SiC Power Integrated Circuits

   Författare :Saleh Kargarrazi; Carl-Mikael Zetterling; Ana Rusu; Shankar Narayanan Ekkanath Madathil; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Informations- och kommunikationsteknik; Information and Communication Technology;

   Sammanfattning : In the recent decade, integrated electronics in wide bandgap semiconductor technologies such as Gallium Nitride (GaN) and Silicon Carbide (SiC) have been shown to be viable candidates in extreme environments (e.g high-temperature and high radiation). Such electronics have applications in down-hole drilling, automobile-, air- and space- industries. LÄS MER

7. 25. Theory and Design of Efficient Active Load Modulation Power Amplifiers

   Författare :Han Zhou; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; GaN; circulator; non-reciprocity; Doherty power amplifier; Combiner synthesis; CLMA; deep power back-off; energy efficiency;

   Sammanfattning : The increasing demand for mobile data traffic has put new challenges and requirements for the development of the wireless communication infrastructure. The performance of the RF power amplifier (PA) is, in particular, of great importance, since it is the key building block for microwave transmitters in base stations and radio link equipment. LÄS MER