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Wideband Gan Microwave Power Amplifiers With Class G Supply Modulation Band 48
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Book Synopsis Wideband GaN Microwave Power Amplifiers with Class-G Supply Modulation (Band 48 by : Nikolai Wolff
Download or read book Wideband GaN Microwave Power Amplifiers with Class-G Supply Modulation (Band 48 written by Nikolai Wolff and published by FBI / Ferdinand Braun Institut. This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The continuous and rapidly growing demand for mobile communication access led to a major increase in the number of base stations worldwide to provide sufficient coverage and quality of service. As a consequence, mobile communication networks have become a significant contributor to global energy consumption. Several advanced topologies for efficiency improvement of RF power amplifiers have been developed. Modulating the amplifier's supply voltage according to the variation of the envelope signal is one of the most promising concepts. This topology is investigated here, with an architecture that switches the supply voltage of the power amplifier in discrete levels with a class-G supply modulator. The thesis addresses comprehensively all aspects of class-G supply modulation. Several prototype designs were realized to validate the theory and to gain experience on the influence of the corresponding parameters. These include the discrete supply voltage levels, the switching thresholds, and the interface between the RF PA and the class-G supply modulator. Efforts both on improving the RF power amplifiers and developing several class-G supply modulators were also involved. This work covers the progress up to a PA module that provides an instantaneous modulation bandwidth of 120 MHz and achieves better performance than state-of-the art continuous supply modulation systems. Class-G supply modulated RF power amplifiers based on gallium nitride technology exhibit a strong nonlinear behavior, therefore linearization is required. For this purpose, the linearization with digital predistortion based on behavioral models is optimized for the class-G topology and a novel predistorter model is developed and analyzed.
Book Synopsis Wideband GaN Microwave Power Amplifiers with Class-G Supply Modulation by : Nikolai Wolff
Download or read book Wideband GaN Microwave Power Amplifiers with Class-G Supply Modulation written by Nikolai Wolff and published by Cuvillier Verlag. This book was released on 2019-02-06 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: The continuous and rapidly growing demand for mobile communication access led to a major increase in the number of base stations worldwide to provide sufficient coverage and quality of service. As a consequence, mobile communication networks have become a significant contributor to global energy consumption. Several advanced topologies for efficiency improvement of RF power amplifiers have been developed. Modulating the amplifier’s supply voltage according to the variation of the envelope signal is one of the most promising concepts. This topology is investigated here, with an architecture that switches the supply voltage of the power amplifier in discrete levels with a class-G supply modulator. The thesis addresses comprehensively all aspects of class-G supply modulation. Several prototype designs were realized to validate the theory and to gain experience on the influence of the corresponding parameters. These include the discrete supply voltage levels, the switching thresholds, and the interface between the RF PA and the class-G supply modulator. Efforts both on improving the RF power amplifiers and developing several class-G supply modulators were also involved. This work covers the progress up to a PA module that provides an instantaneous modulation bandwidth of 120 MHz and achieves better performance than state-of-the art continuous supply modulation systems. Class-G supply modulated RF power amplifiers based on gallium nitride technology exhibit a strong nonlinear behavior, therefore linearization is required. For this purpose, the linearization with digital predistortion based on behavioral models is optimized for the class-G topology and a novel predistorter model is developed and analyzed.
Book Synopsis Design, simulation and analysis of laterally-longitudinally non-uniform edge-emitting GaAs-based diode lasers (Band 73) by : Jan-Philipp Koester
Download or read book Design, simulation and analysis of laterally-longitudinally non-uniform edge-emitting GaAs-based diode lasers (Band 73) written by Jan-Philipp Koester and published by Cuvillier Verlag. This book was released on 2023-09-19 with total page 171 pages. Available in PDF, EPUB and Kindle. Book excerpt: Edge-emitting quantum-well diode lasers based on GaAs combine a high conversion efficiency, a wide range of emission wavelengths covering a span from 630 nm to 1180 nm, and the ability to achieve high output powers. The often used longitudinal-invariant Fabry-Pérot-type resonators are easy to design but often lead to functionality or performance limitations. In this work, the application of laterally-longitudinally non-uniform resonator configurations is explored as a way to reduce unwanted and performance-limiting effects. The investigations are carried out on existing and entirely newly developed laser designs using dedicated simulation tools. These include a sophisticated time-dependent laser simulator based on a traveling-wave model of the optical fields in the lateral-longitudinal plane and a Maxwell solver based on the eigenmode expansion method for the simulation of passive waveguides. Whenever possible, the simulation results are compared with experimental data. Based on this approach, three fundamentally different laser types are investigated: • Dual-wavelength lasers emitting two slightly detuned wavelengths around 784 nm out of a single aperture • Ridge-waveguide lasers with tapered waveguide and contact layouts that emit light of a wavelength of around 970 nm • Broad-area lasers with slightly tapered contact layouts emitting at 910 nm The results of this thesis underline the potential of lateral-longitudinal non-uniform laser designs to increase selected aspects of device performance, including beam quality, spectral stability, and output power.
Book Synopsis Design of High Power, Wideband Microwave Frequency Class F Power Amplifiers Using AlGaN/GaN HEMTs by : Jeffrey Lee Tan
Download or read book Design of High Power, Wideband Microwave Frequency Class F Power Amplifiers Using AlGaN/GaN HEMTs written by Jeffrey Lee Tan and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents the theory, design, and implementation of two high power (>10 W) RF power amplifiers operating in the S-band (2 to 4 GHz) and employing the Class F mode of efficiency enhancement. The amplifiers are based around gallium nitride (GaN) high electron mobility transistors (HEMTs) which provide the high power capability. A complex wideband design using synthesized low-pass transforming filters as large-bandwidth matching networks is presented, followed by a more elegant narrowband design employing simple stub matching networks for impedance matching and harmonic control. Also presented in this thesis is a detailed study into the computer modeling of the GaN HEMT devices in order to accurately predict their behavior when integrated into a system. A complete small-signal circuit model is developed which is capable of predicting the scattering parameters of the devices with a high degree of accuracy to the measured behavior. Large-signal device models of increasing complexity are studied to investigate fundamental behaviors of field-effect transistors for which HEMTs are a subset. Finally, the manufacturer design kit’s computer model is investigated and verified for accuracy with the measured results.An overview of power amplifier design and classes of operation is given, and specifically Class F theory and implementation are analyzed. The efficiency enhancement by waveform shaping is studied, as well as the mechanism of waveform shaping via harmonic manipulation. Once fabricated and tested, the wideband design is shown to achieve at least 38.8 dBm output power between 2.2 to 3.3 GHz centered around 2.75 GHz, giving a fractional bandwidth of 40%. Over that range, the PA is able to sustain PAE > 40%, with a peak efficiency of 61%. The narrowband design achieves an output power at its center frequency of 3 GHz of 41.48 dBm, or ~14 W, with the PAE achieving a maximum of approximately 66%.
Book Synopsis A deep ultraviolet laser light source by frequency doubling of GaN based external cavity diode laser radiation by : Norman Ruhnke
Download or read book A deep ultraviolet laser light source by frequency doubling of GaN based external cavity diode laser radiation written by Norman Ruhnke and published by Cuvillier Verlag. This book was released on 2022-05-13 with total page 130 pages. Available in PDF, EPUB and Kindle. Book excerpt: A compact and portable laser light source emitting in the wavelength range between 210 nm and 230 nm would enable numerous applications outside of laboratory environments, such as sterilization and disinfection of medical equipment, water purification or gas and air analysis using absorption spectroscopy. Such a source is also highly attractive for the identification and quantification of proteins and biomolecules by means of laser-induced fluorescence or Raman spectroscopy. In this thesis, a novel concept to realize such a compact and portable laser light source with low power consumption and an emission around 222 nm is investigated. The developed concept is based on single-pass frequency doubling of a commercially available high-power GaN laser diode emitting in the blue spectral range. Due to the low frequency doubling conversion efficiencies in this wavelength range of about 10-4 W-1, a laser diode with high optical output power above 1 W is required as pump source. Moreover, it has to exhibit narrowband emission in the range of the acceptance bandwidth of the applied nonlinear BBO crystal. Since GaN-based high-power laser diodes typically show broad emission spectra of Δλ = 1…2 nm, stabilizing and narrowing their wavelength by using external wavelength-selective elements is investigated and presented for the first time. With the understanding for the novel concept gained in this work, a compact ultraviolet laser light source was realized. It has a power consumption of less than 10 W and is exceptionally robust due to its immoveable components. The demonstrated output power of 160 μW enables numerous industrial and everyday applications for which previous laser systems have been too complex and overly cost- and energy-intensive.
Book Synopsis Two-step MOVPE, in-situ etching and buried implantation: applications to the realization of GaAs laser diodes by : Pietro della Casa
Download or read book Two-step MOVPE, in-situ etching and buried implantation: applications to the realization of GaAs laser diodes written by Pietro della Casa and published by Cuvillier Verlag. This book was released on 2021-03-25 with total page 250 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work is about two-step epitaxial growth using metalorganic vapor-phase epitaxy (MOVPE) for the realization of edge-emitting near-infrared laser diodes. The fabricated gallium arsenide-based devices fall into two categories: high-power lasers (watt range, multimodal) and tunable lasers (milliwatt range, monomodal). Common to both cases is that surface contamination – particularly that due to oxygen – needs to be removed before regrowth. Thus, in-situ etching with carbon tetrabromide (CBr4) is first studied. The experimental results include kinetic data, the effects of different etching conditions as well as substrate characteristics, and the effectiveness in reducing surface contamination. These investigations pave the way to devices based on 2-step epitaxy combined with in-situ etching. Correspondingly, thermally-tuned SG-DBR lasers operating around 975 nm have been successfully realized, obtaining a tuning range of 21 nm. In addition, the possibility of using electronic tuning in similar devices has been explored. High-power broad-area lasers have also been realized, using two-step epitaxy combined with ex-situ and in-situ etching, to create a buried, shallow “mesa” containing the active zone. This approach allows introducing lateral electrical and optical confinement, and – simultaneously – non-absorbing mirrors at the laser facets. Additionally, a different strategy to create a buried current aperture is presented, which is based on ion implantation followed by epitaxial regrowth. This enables to improve device performance and simultaneously introduce non-absorbing mirrors at the facets with correspondingly increased reliability.
Book Synopsis Transceiver Technologies for Millimeter-Wave Beam Steering Applications (Band 71) by : Yi-Fan Tsao
Download or read book Transceiver Technologies for Millimeter-Wave Beam Steering Applications (Band 71) written by Yi-Fan Tsao and published by Cuvillier Verlag. This book was released on 2022-11-08 with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the past years, wireless communication systems have been rapidly advancing to meet the high data-rate requirements of various emerging applications. However, the existing transceivers have typically been demonstrated using CMOS-compatible technologies that deliver a relatively low equivalent isotropic radiated power in a small unit cell. Moreover, the particular device characteristics are limiting the linear region for operation. Therefore, the main focus of this dissertation is to present and discuss new design methods for transceivers to solve these issues. To reduce the complexity of the transceiver module for further phased-array scaling, a low-noise power amplifier design approach is designed using a 0.15-μm GaN-on-SiC high-electron mobility transistor technology (HEMT). Utilizing a traded off interstage matching topology between loss and bandwidth, the conversion loss induced by the matching network could be effectively reduced. A stacked-FET configuration was adopted to enhance the power handling of the RF switch. Further improvement on the isolation bandwidth was investigated using theoretical analysis on the intrinsic effect of the passive HEMTs. With the successful implementation of the RF front-end circuits, transceiver modules were integrated on Rogers RO3010 substrate. The planar dual exponentially tapered slot antenna phased-array system showed a compact size with simple biasing network compared to the conventional transceiver approach. The presented T/R module was characterized with an over-the-air test at a distance of 1 m, overcoming the free space path loss of 64 dB. It also shows a high flexibility for further integration with a larger number of array systems, which is very promising for future 5G communication systems.
Book Synopsis Microwave High Power High Efficiency GaN Amplifiers for Communication by : Subhash Chandra Bera
Download or read book Microwave High Power High Efficiency GaN Amplifiers for Communication written by Subhash Chandra Bera and published by Springer Nature. This book was released on 2022-11-29 with total page 263 pages. Available in PDF, EPUB and Kindle. Book excerpt: The textbook discusses design and analysis of microwave high power and high efficiency amplifiers for communications, appropriate for undergraduate, post-graduate students, practical circuit designers and researchers in the field of electronics and communication engineering. This book covers basics of III-V group semiconductor materials and GaAs and GaN based High Electron Mobility Transistors (HEMTs) most suitable for microwave and mm wave power amplifiers required for present wireless communication systems and upcoming 4G and 5G mobile base stations. The book describes design and analysis of classical class of amplifier operations such as Class-A, B, AB, C and F. The coverage extends to advanced classes of amplifier operation such as extended continuous Class-B/Class-J, and extended continuous Class-F operations for broadband, high power and high efficiency performance. Analytical expressions are derived for circuit elements and performance parameters for clear understanding and required for practical design of power amplifiers. Each topic is supplemented with suitable schematic diagrams, analytical expressions and plotted results for clear understanding.
Book Synopsis Solid-state Microwave High-power Amplifiers by : Franco Sechi
Download or read book Solid-state Microwave High-power Amplifiers written by Franco Sechi and published by Artech House. This book was released on 2009 with total page 333 pages. Available in PDF, EPUB and Kindle. Book excerpt: This practical resource offers expert guidance on the most critical aspects of microwave power amplifier design. This comprehensive book provides descriptions of all the major active devices, discusses large signal characterization, explains all the key circuit design procedures. Moreover you gain keen insight on the link between design parameters and technological implementation, helping you achieve optimal solutions with the most efficient utilization of available technologies. The book covers a broad range of essential topics, from requirements for high-power amplifiers, device models, phase noise and power combiners... to high-efficiency amplifiers, linear amplifier design, bias circuits, and thermal design.
Book Synopsis Analysis of Spatio-Temporal Phenomena in High-Brightness Diode Lasers using Numerical Simulations by : Anissa Zeghuzi
Download or read book Analysis of Spatio-Temporal Phenomena in High-Brightness Diode Lasers using Numerical Simulations written by Anissa Zeghuzi and published by Cuvillier Verlag. This book was released on 2020-10-22 with total page 176 pages. Available in PDF, EPUB and Kindle. Book excerpt: Broad-area lasers are edge-emitting semiconductor lasers with a wide lateral emission aperture. This feature enables high output powers but also diminishes the lateral beam quality and results in their inherently non-stationary behavior. Research in the area is driven by application, and the main objective is to increase the brightness, which includes both output power and lateral beam quality. To understand the underlying spatio-temporal phenomena and to apply this knowledge in order to reduce costs for brightness optimization, a self-consistent simulation tool taking all essential processes into account is vital. Firstly, in this work a quasi-three-dimensional opto-electronic and thermal model is presented that describes essential qualitative characteristics of real devices well. Time-dependent traveling-wave equations are utilized to characterize the inherently non-stationary optical fields, which are coupled to dynamic rate equations for the excess carriers in the active region. This model is extended by an injection-current-density model to accurately include lateral current spreading and spatial hole burning. Furthermore, a temperature model is presented that includes short-time local heating near the active region as well as the formation of a stationary temperature profile. Secondly, the reasons of brightness degradation, i.e. the origins of power saturation and the spatially modulated field profile, are investigated. And lastly, designs that mitigate those effects limiting the lateral brightness under pulsed and continuous-wave operation are discussed. Amongst those designs a novel “chessboard laser” is presented that utilizes longitudinal-lateral gain-loss modulation and an additional phase tailoring to obtain a very low far-field divergence.
Book Synopsis Spectroscopic Applications of Terahertz Quantum-Cascade Lasers by : Tasmim Alam
Download or read book Spectroscopic Applications of Terahertz Quantum-Cascade Lasers written by Tasmim Alam and published by Cuvillier Verlag. This book was released on 2020-10-29 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quantum cascade lasers (QCLs) are attractive for high-resolution spectroscopy because they can provide high power and a narrow linewidth. They are particularly promising in the terahertz (THz) range since they can be used as local oscillators for heterodyne detection as well as transmitters for direct detection. However, THz QCL-based technologies are still under development and are limited by the lack of frequency tunability as well as the frequency and output power stability for free-running operation. In this dissertation, frequency tuning and linewidth of THz QCLs are studied in detail by using rotational spectroscopic features of molecular species. In molecular spectroscopy, the Doppler eff ect broadens the spectral lines of molecules in the gas phase at thermal equilibrium. Saturated absorption spectroscopy has been performed that allows for sub-Doppler resolution of the spectral features. One possible application is QCL frequency stabilization based on the Lamb dip. Since the tunability of the emission frequency is an essential requirement to use THz QCL for high-resolution spectroscopy, a new method has been developed that relies on near-infrared (NIR) optical excitation of the QCL rear-facet. A wide tuning range has been achieved by using this approach. The scheme is straightforward to implement, and the approach can be readily applied to a large class of THz QCLs. The frequency and output stability of the local oscillator has a direct impact on the performance and consistency of the heterodyne spectroscopy. A technique has been developed for a simultaneous stabilization of the frequency and output power by taking advantage of the frequency and power regulation by NIR excitation. The results presented in this thesis will enable the routine use of THz QCLs for spectroscopic applications in the near future.
Book Synopsis AlN base layers for UV LEDs by : Sebastian Walde
Download or read book AlN base layers for UV LEDs written by Sebastian Walde and published by Cuvillier Verlag. This book was released on 2021-06-22 with total page 156 pages. Available in PDF, EPUB and Kindle. Book excerpt: To enable the fabrication of high performance ultraviolet (UV) light-emitting diodes (LEDs) this work aims at improving the quality of AlN base layers on sapphire substrates. The main issues for UV LEDs are still a limited internal quantum efficiency due to a high amount of threading dislocations along with a limited light extraction efficiency due to total internal reflection at the AlN/sapphire interface. Therefore, high-temperature annealing of AlN/sapphire layers and growth on nanopatterned sapphire substrates were comprehensively investigated. High-temperature annealing was applied to AlN layers of different strain and thickness grown by metalorganic vapour phase epitaxy (MOVPE). The threading dislocation density could be successfully reduced by more than one order of magnitude down to 6 × 108 cm-2. Wave optical simulations of UV LEDs on nanopatterned sapphire substrates (NPSS) were conducted and showed a potential increase in light extraction efficiency compared to a planar substrate. The optimized MOVPE growth process on sapphire nanopillars and sapphire nanoholes resulted in a fully coalesced and atomically smooth AlN surface. The threading dislocation density was reduced to 1 ×109 cm-2 for AlN on both nanopillars and nanoholes. UVC LEDs emitting at 265 nm wavelength were grown on top of the developed templates. Increased internal efficiency was obtained by reduced dislocation density and more efficient light extraction was achieved on NPSS in case of a transparent heterostructure and reflective contacts. Thus, the developed templates yield considerable improvement in light output compared to conventional templates.
Book Synopsis Broad-Area Laser Bars for 1 kW-Emission by : Matthias M. Karow
Download or read book Broad-Area Laser Bars for 1 kW-Emission written by Matthias M. Karow and published by Cuvillier Verlag. This book was released on 2022-06-27 with total page 143 pages. Available in PDF, EPUB and Kindle. Book excerpt: ndustrial laser systems for material processing applications rely on the availability of highly efficient, high-brightness diode lasers. GaAs-based broad-area laser bars play a vital role in such applications as pump sources for high-beam-quality solid-state lasers and, increasingly, as direct processing tools. This work studies 940 nm-laser bars emitting 1 kW optical power at room temperature, identifying those physical mechanisms that are currently limiting electrical-to-optical conversion efficiency as well as lateral beam quality. In the process, several diagnostic studies on bars with varied lateral-longitudinal design were carried out. The effects of technological measures for performance optimization were analyzed, yielding a new benchmark in efficiency and lateral divergence. The studies into altered resonator lengths of 4 and 6 mm as well as fill factors between 69 and 87 % successfully reduce both the voltage dropping across the device and power saturation at high currents, enabling 66 % efficiency at the operation point. Concrete measures how to reach efficiencies ≥70 % are presented thereafter, showing that doubling the efficiency value of the first 1 kW-demonstration in 2007 – amounting to 35 % – is in near reach. Investigation of the beam quality bases on a herein proposed and realized concept, in which the far field is resolved for each individual bar emitter. In this way, it is possible to determine how far-field profiles vary along the bar width and how much these variations affect the overall bar far-field. Further, such effects specific to bar structures can be separated into non-thermal and thermal influences. The effect of mechanical chip deformation (bar smile) as well as neighboring-emitter interaction has been investigated for the first time in active kW-class devices, yielding a lateral divergence as low as 8.8° at the operation point.
Book Synopsis Development of GaN Based Microwave Power Amplifier for X Band Applications by :
Download or read book Development of GaN Based Microwave Power Amplifier for X Band Applications written by and published by . This book was released on 2000 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The feasibility of utilizing the GaN/AlGaN material system in the development of high power amplifiers for X-band frequencies and above was investigated. The GaN based heterojunction field effect transistor (HFET) on SiC shows remarkable power density at microwave frequencies. An order of magnitude improvement can be attained in output power when compared with present GaAs devices, judging from the already observed power density along with further anticipated advances of these GaN devices. Four individual HFET devices operating in combination were able to achieve 6 watts (W) output at 9.4 Ghz. The investigation into improving this performance for Phase Ii research is documented.
Book Synopsis Distributed Power Amplifiers for RF and Microwave Communications by : Narendra Kumar
Download or read book Distributed Power Amplifiers for RF and Microwave Communications written by Narendra Kumar and published by Artech House. This book was released on 2015-06-01 with total page 365 pages. Available in PDF, EPUB and Kindle. Book excerpt: This new resource presents readers with all relevant information and comprehensive design methodology of wideband amplifiers. This book specifically focuses on distributed amplifiers and their main components, and presents numerous RF and microwave applications including well-known historical and recent architectures, theoretical approaches, circuit simulation, and practical implementation techniques. A great resource for practicing designers and engineers, this book contains numerous well-known and novel practical circuits, architectures, and theoretical approaches with detailed description of their operational principles.
Book Synopsis Design of Power-scalable Gallium Nitride Class E Power Amplifiers by : Mark Anthony Connor
Download or read book Design of Power-scalable Gallium Nitride Class E Power Amplifiers written by Mark Anthony Connor and published by . This book was released on 2014 with total page 102 pages. Available in PDF, EPUB and Kindle. Book excerpt: The need for high power, highly efficient, multi-band and multi-mode radio frequency (RF) and microwave power amplifiers in the commercial and defense wireless industries continues to drive the research and development of gallium nitride (GaN) devices and their implementation in the receiver and transmitter lineups of modern microwave systems. Unlike silicon (Si) or gallium arsenide (GaAs), GaN is a direct wide bandgap semiconductor that permits usage in high voltage and therefore high power applications. Additionally, the increased saturation velocity of GaN allows for operation well into the super high frequency (SHF) portion of the RF spectrum. For the power amplifier designer, active devices utilizing GaN will exhibit power densities almost an order of magnitude greater than comparably sized GaAs devices and almost two orders of magnitude greater than Si devices. Not only does this mean an overall size reduction of an amplifier for a given output power, but it allows GaN to replace specialized components such as the traveling-wave tube (TWT) and other circuits once deemed impossible to realize using solid-state electronics. Designs utilizing GaN in amplifiers, switches, mixers, etc., are able to meet the continually shrinking size, increased power, stringent thermal, and cost requirements of a modern microwave system.There are two relatively straight forward methods used to investigate the intrinsic power scaling properties of a GaN high-electron-mobility transistor (HEMTs) configured as a common source amplifier. The first method involves sweeping the applied drain to source voltage bias and the second method involves scaling the physical size of the transistor. The prior method can be used to evaluate fixed sized transistors while the latter method requires an understanding of the obtainable power density for a given device technology prior to fabrication. Since the power density is also a function of the drain to source voltage bias, an initial iterative component of the design cycle may be required to fully characterize the device technology. If a scalable nonlinear device model is available to the designer, the harmonic balance simulator in most computer aided design (CAD) tools can be used to evaluate device parameters such as the maximum output power and power added efficiency (PAE) using large signal load pull simulations.The circuits presented in this thesis address two power amplifier design approaches commonly used in industry. The first approach utilizes commercially available bare die GaN transistors that can be wire-bonded to matching circuitry on a printed circuit board (PCB). This technique is known as hybrid packaging. The second approach utilizes a fully integrated design or monolithic microwave integrated circuit (MMIC) and the process design kit (PDK) used to design, simulate and layout the power amplifier circuitry before submission to a foundry for fabrication. In both cases, the nonlinear transistor models are used to investigate the power scalability of class E mode GaN power amplifiers and the techniques used to implement such circuits. The design, results, and challenges of each approach are discussed and future work is presented.
Book Synopsis Dynamic Power Supply Transmitters by : Earl McCune
Download or read book Dynamic Power Supply Transmitters written by Earl McCune and published by Cambridge University Press. This book was released on 2015-05-21 with total page 495 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Power is dissipated (lost) when this current flows through any resistance, which includes the amplifier's transistor. This dissipated power is the product of the current in the load times the voltage difference between the supply voltage to the amplifier and the output signal voltage. When the voltage supplied to the amplifier is a constant value, and by far the most common design practice, the situation in Fig. 1-2a results. Power dissipation in the amplifier is maximum when the output signal voltage is 1/2 of the supply voltage. When the output signal voltage is higher, even though the current value is larger the voltage drop is less and the power dissipation is lower. Similarly, when the output signal voltage is small, even though the voltage drop is now large the current in the load is smaller and again the power dissipation is lower"--
