Sökning: "load modulation"

Visar resultat 1 - 5 av 55 avhandlingar innehållade orden load modulation.

  1. 1. Analytical Approaches to Load Modulation Power Amplifier Design

    Författare :William Hallberg; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; linear; load modulated balanced amplifier LMBA ; Active load-pull; radio frequency RF ; Wilkinson power divider.; load modulation; energy efficiency; microwave; power amplifier PA ; Doherty;

    Sammanfattning : In future mobile communication networks, there will be a shift toward higher carrier frequencies and highly integrated multiple antenna systems. The system performance will largely depend on the available radio frequency (RF) hardware. As such, RF power amplifiers (PAs) with improved performance, e.g. LÄS MER

  3. 2. SiC Varactors for Dynamic Load Modulation of Microwave Power Amplifiers

    Författare :Christer Andersson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nonlinear characterization; varactors; active load-pull; power; microwave; amplifier; dynamic load modulation; SiC; energy efficiency;

    Sammanfattning : The rapid consumer adoption of mobile services is leading to an exponential growth in wireless data traffic. In order to accommodate more concurrent high data-rate users, the required complexity of transmitting radio base station (RBS) power amplifiers (PAs) is increasing. LÄS MER

  4. 3. High Efficiency Microwave Amplifiers and SiC Varactors Optimized for Dynamic Load Modulation

    Författare :Christer Andersson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; nonlinear measurements; power amplifiers; load modulation; GaN; SiC; varactors; HEMT; wide bandgap technology; energy efficiency;

    Sammanfattning : The increasing use of mobile networks as the main source of internet connectivity is creating challenges in the infrastructure. Customer demand is a moving target and continuous hardware developments are necessary to supply higher data rates in an environmentally sustainable and cost effective way. LÄS MER

  5. 4. Effects of visual load on auditory processing

    Författare :Malina Szychowska; Stefan Wiens; Mats E. Nilsson; Maria Larsson; Inga Griskova-Bulanova; Stockholms universitet; []
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; EEG; event-related potential; mismatch negativity; auditory steady-state response; envelope following response; perceptual load; visual load; task difficulty; crossmodal attention; early-filter theory; adaptive filtering model; Psychology; psykologi;

    Sammanfattning : In daily life, people need to be able to focus on a task while ignoring any task-irrelevant background noise. For example, people who work in an open-space office may have to work on a report while ignoring the background talk among co-workers. LÄS MER

  7. 5. High efficiency power amplifiers for wireless communications

    Författare :Hossein Mashad Nemati; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; load modulation; GaN; supply modulation; LDMOS; efficiency; Power amplifier; MMIC; mHEMT; transmitter architecture;

    Sammanfattning : This thesis presents state-of-the-art high efficiencyharmonically-tuned power amplifiers (PAs) and investigates thecharacteristics and potentials of such amplifiers in two of the mostpromising efficiency enhancement techniques, dynamic supply and load modulation.In this work, a 10 W LDMOS harmonically-tuned PA with 80% power-added-efficiency (PAE) isrealized at 1 GHz. LÄS MER