Sökning: "power amplifier PA"

Visar resultat 11 - 15 av 30 avhandlingar innehållade orden power amplifier PA.

  1. 11. Frequency Reconfigurable and Linear Power Amplifiers Based on Doherty and Varactor Load Modulation Techniques

    Författare :William Hallberg; Chalmers University of Technology; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; gallium nitride GaN ; wideband; Class-J; linear; microwave; radio frequency RF ; Doherty; broadband; AM AM; silicon carbide SiC ; bandwidth; power amplifier PA ; AM PM; varactor; dynamic load modulation DLM ; fifth generation mobile networks 5G ; energy efficiency;

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

  2. 12. Extending the Bandwidth of the Doherty Power Amplifier

    Författare :David Gustafsson; Chalmers University of Technology; []

    Sammanfattning : The Doherty power amplifier (DPA) is one of the most popular power amplifier (PA) architectures used to obtain high efficiency for modern communication signals having high peak-to-average power ratios. Its often narrowband performance does, however, make it difficult for the DPA to meet the increasing demands of frequency agility in modern wireless communication systems. LÄS MER

  3. 13. Estimation of Inverse Models Applied to Power Amplifier Predistortion

    Författare :Ylva Jung; Martin Enqvist; Lennart Ljung; Torkel Glad; Mikael Sternad; Linköpings universitet; []
    Nyckelord :;

    Sammanfattning : Mathematical models are commonly used in technical applications to describe the behavior of a system. These models can be estimated from data, which is known as system identification. Usually the models are used to calculate the output for a given input, but in this thesis, the estimation of inverse models is investigated. LÄS MER

  4. 14. Characterization and Compensation of Hardware Impairments in Transmitters for Wireless Communications

    Författare :Zain Ahmed Khan; Peter Händel; Magnus Isaksson; Mikko Valkama; KTH; []
    Nyckelord :ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Power amplifier; RF transmitters; SISO; MIMO; crosstalk; Volterra series; Volterra kernels; behavioral modeling; DPD; Ramanujan sums; multitone signals; I Q Imbalance; non-linearity; memory polynomial; density estimation; hardware impairments; Electrical Engineering; Elektro- och systemteknik;

    Sammanfattning : Increasing demands for data rate, energy efficiency and reliability in wireless communications have resulted in the introduction of radio frequency (RF) multiple input multiple output (MIMO) transmitters. However, MIMO transmitters suffer from additional crosstalk impairments along with the power amplifier (PA) and I/Q imbalance distortions observed in single input single output (SISO) transmitters. LÄS MER

  5. 15. Microwave FET Modeling and Applications

    Författare :Christian Fager; Chalmers University of Technology; []
    Nyckelord :MESFET; uncertainty; model; FMCW; statistical; HEMT; small-signal; extraction; distortion; intermodulation; CMOS; LDMOS; power amplifier; estimation; FET; large-signal; radar; AM noise;

    Sammanfattning : This thesis deals with three distinct topics within the areas of modeling, analysis and circuit design with microwave field effect transistors (FETs). First, the extraction of FET small-signal model parameters is addressed. LÄS MER