Search for dissertations about: "wideband signals"

Showing result 1 - 5 of 36 swedish dissertations containing the words wideband signals.

  1. 1. Theory and Design of Wideband Doherty Power Amplifiers

    Author : David Gustafsson; [2012]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Doherty; gallium nitride; GaN; power amplifier; MMIC; microwave; Broadband amplifiers; high efficiency; wideband;

    Abstract : The Doherty power amplifier (DPA) is one of the most popular power amplifier architectures for obtaining high average efficiency for modern communication signals with high peak-to-average power ratios (PAPR). However, the DPA suffers from often having narrowband performance which limits its capabilities in wideband and/or multi-standard microwave and radio frequency applications. READ MORE

  2. 2. Efficient and Wideband Power Amplifiers for Wireless Communications

    Author : Paul Saad; [2012]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; multi-band; Doherty power amplifier; high efficiency; Branch-line coupler; wideband.; power amplifier; GaN-HEMT;

    Abstract : The rapid evolution of wireless communication systems and the developmentof new standards require that wireless transmitters process several types ofstandards across multiple bands. Power amplifiers (PAs) are key componentsin wireless transmitters because they have a big impact on the overall systemperformance in terms of their bandwidth, efficiency, and linearity. READ MORE

  3. 3. Compact and Efficient Millimetre-Wave Circuits for Wideband Applications

    Author : Lars Ohlsson; [2015]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; resonant-tunnelling diode; millimetre-wave spectrum; integrated transmitter; energy-efficiency; compact circuit; dielectric resonator antenna; transistor; wavelet generator; wideband.;

    Abstract : Radio systems, along with the ever increasing processing power provided by computer technology, have altered many aspects of our society over the last century. Various gadgets and integrated electronics are found everywhere nowadays; many of these were science-fiction only a few decades ago. READ MORE

  4. 4. Nonlinear Characterization of Wideband Microwave Devices and Dispersive Effects in GaN HEMTs

    University dissertation from Gothenburg : Chalmers tekniska högskola

    Author : Sebastian Gustafsson; [2018]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; large-signal; dispersive effects; electron trapping; thermal coupling; HEMT; GaN; microwave; wideband;

    Abstract : Measurements play a key role in the development of microwave hardware as they allow engineers to test and verify the RF performance on a system, circuit, and component level. Since modern cellular standards employ complex modulation formats with wider signal bandwidths to cope with the growing demand of higher datarates, nonlinear characterization using wideband stimuli is becoming increasingly important. READ MORE

  5. 5. Ultra-Wideband Time Domain Measurement Systems for Microwave Tomography

    University dissertation from Gothenburg : Chalmers tekniska högskola

    Author : Xuezhi Zeng; [2010]
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Time DomainMeasurement; Ultra-Wideband; EquivalentTime Sampling; Real Time Sampling; Microwave Tomography; Measurement Error; Frequency Domain Measurement;

    Abstract : As a potential imaging modality for biomedical applications, microwave tomography has attracted a lot of interests in recent years. With microwave tomography, microwave signals are transmitted into the biological tissues and the scattered fields are recorded. READ MORE