Sökning: "dynamic efficiency"

Visar resultat 1 - 5 av 586 avhandlingar innehållade orden dynamic efficiency.

  1. 1. Linearization of High Efficiency Transmitters for Wireless Communications

    Författare :Haiying Cao; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; dynamic load modulation; Behavioral model; digital predistortion; I Q imbalance; Volterra series; efficiency; power amplifier; transmitter;

    Sammanfattning : In recent years, reducing energy consumption in wirelesscommunication systems has gained prominence. In order to achieve this energy saving, high power efficiency is necessary for the wireless transmitters used. LÄS MER

  3. 2. 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

  4. 3. Modeling Complex Engines as Dynamic Powertrain Members

    Författare :Sixten Berglund; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; vehicle; diesel engine; simulation; supercharging; drivability; toolbox; fuel economy; transient; modeling; turbocharging; control system; powertrain; emissions; performance; dynamic; system;

    Sammanfattning : Engine modeling and simulation have been necessary tools for efficient product development in the automotive industry for some time. The scope of this work is novel engine models, tools, and methods for powertrain research and development. LÄS MER

  5. 4. Seasonal Adjustment and Dynamic Linear Models

    Författare :Can Tongur; Daniel Thorburn; Sune Karlsson; Stockholms universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Dynamic linear models; DLM; direct and indirect seasonal adjustment; relative efficiency; Huber loss function; Polls of polls; Wiener process; Swedish elections; Statistics; statistik;

    Sammanfattning : Dynamic Linear Models are a state space model framework based on the Kalman filter. We use this framework to do seasonal adjustments of empirical and artificial data. A simple model and an extended model based on Gibbs sampling are used and the results are compared with the results of a standard seasonal adjustment method. LÄS MER

  7. 5. 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