AlGaN/GaN-HEMT power amplifiers with optimized power-added efficiency for X-band applications

AlGaN/GaN-HEMT power amplifiers with optimized power-added efficiency for X-band applications
Author: Jutta Kühn
Publisher: KIT Scientific Publishing
Total Pages: 264
Release: 2011
Genre: Power amplifiers
ISBN: 3866446152

This work has arisen out of the strong demand for a superior power-added efficiency (PAE) of AlGaN/GaN high electron mobility transistor (HEMT) high-power amplifiers (HPAs) that are part of any advanced wireless multifunctional RF-system with limited prime energy. Different concepts and approaches on device and design level for PAE improvements are analyzed, e.g. structural and layout changes of the GaN transistor and advanced circuit design techniques for PAE improvements of GaN HEMT HPAs.

ICCWCS 2019

ICCWCS 2019
Author: Jamal Zbitou
Publisher: European Alliance for Innovation
Total Pages: 564
Release: 2019
Genre: Technology & Engineering
ISBN: 1631901818

Today, computer science engineering and telecommunications are two important areas linked and even inseparable. This is obvious for the user who connects the modem of his computer on his mobile phone or telephone line to access, via the global data network, the information available on the servers. The both domains are evolving rapidly and the development of new architectures of systems dedicated to telecommunications and computing becomes essential. Especially, wireless transmission systems with high data rate. Two parts of these systems should be developed software and hardware. Another area that is renewable energies becomes more attractive for researchers in order to develop new conversion systems with good performances, and a good optimization of energy. For example, in wireless sensor systems, we try to develop new protocols permitting to have a good autonomy in terms of energy.

Motion Compensation for Near-Range Synthetic Aperture Radar Applications

Motion Compensation for Near-Range Synthetic Aperture Radar Applications
Author: Huaming Wu
Publisher: KIT Scientific Publishing
Total Pages: 182
Release: 2014-07-30
Genre: Technology & Engineering
ISBN: 3866449062

The work focuses on the analysis of influences of motion errors on near-range SAR applications and design of specific motion measuring and compensation algorithms. First, a novel metric to determine the optimum antenna beamwidth is proposed. Then, a comprehensive investigation of influences of motion errors on the SAR image is provided. On this ground, new algorithms for motion measuring and compensation using low cost inertial measurement units (IMU) are developed and successfully demonstrated.

Active Radar Cross Section Reduction

Active Radar Cross Section Reduction
Author: Hema Singh
Publisher: Cambridge University Press
Total Pages: 354
Release: 2015-03-02
Genre: History
ISBN: 1107092612

This book discusses the active and passive radar cross section (RCS) estimation and techniques to examine the low observable aerospace platforms. It begins with the fundamentals of RCS, followed by the dielectric, magnetic and metamaterials parameters of the constituent materials and then explains various methods and the emerging trends followed in this area of study. The RCS estimation of phased array including the mutual coupling effect is also presented in detail in the book. The active RCS reduction is carefully touched upon through the performance of phased arrays, sidelobe cancellers and mitigation of multipath effect. Providing information on various adaptive algorithms like least mean square (LMS), recursive least square (RLS) and weighted least square algorithms, the authors also mention the recent developments in the area of embedded antennas, conformal load bearing antenna, metamaterials and frequency selective surface (FSS) based RCS reduction.

Modeling Backscattering Behavior of Vulnerable Road Users Based on High-Resolution Radar Measurements

Modeling Backscattering Behavior of Vulnerable Road Users Based on High-Resolution Radar Measurements
Author: Abadpour, Sevda
Publisher: KIT Scientific Publishing
Total Pages: 194
Release: 2023-11-20
Genre:
ISBN: 3731513161

During the evolvement of autonomous driving technology, obtaining reliable 3-D environmental information is an indispensable task in approaching safe driving. The operational behavior of automotive radars can be precisely evaluated in a virtual test environment by modeling its surrounding, specifically vulnerable road users (VRUs). Such a realistic model can be generated based on the radar cross section (RCS) and Doppler signatures of a VRU. Therefore, this work proposes a high-resolution RCS measurement technique to determine the relevant scattering points of different VRUs.

High-Precision Automotive Radar Target Simulation

High-Precision Automotive Radar Target Simulation
Author: Diewald, Axel
Publisher: KIT Scientific Publishing
Total Pages: 190
Release: 2023-08-15
Genre:
ISBN: 3731512963

Radar target simulators (RTSs) deceive a radar under test (RuT) by creating an artificial environment consisting of virtual radar targets. In this work, new techniques are presented that overcome the rasterization deficiency of current RTS systems and enable the generation of virtual targets at arbitrary high-precision positions. This allows for continuous movement of the targets and thus a more credible simulation environment.

Intelligent Reflecting Surfaces in Wireless Communication Systems

Intelligent Reflecting Surfaces in Wireless Communication Systems
Author: Li, Yueheng
Publisher: KIT Scientific Publishing
Total Pages: 246
Release: 2024-02-23
Genre:
ISBN: 373151334X

Accompanied with the development of the wireless communication technologies, the high data traffic is more necessary for civil and industrial applications than ever The concept of an intelligent reflective surface (IRS) has attracted considerable attention recently as a low-cost solution. As the main contribution, the dissertation creates new state-of-the-art and formulates a solid milestone for the IRS research field.

III-Nitride Electronic Devices

III-Nitride Electronic Devices
Author:
Publisher: Academic Press
Total Pages: 542
Release: 2019-10-18
Genre: Science
ISBN: 0128175451

III-Nitride Electronic Devices, Volume 102, emphasizes two major technical areas advanced by this technology: radio frequency (RF) and power electronics applications. The range of topics covered by this book provides a basic understanding of materials, devices, circuits and applications while showing the future directions of this technology. Specific chapters cover Electronic properties of III-nitride materials and basics of III-nitride HEMT, Epitaxial growth of III-nitride electronic devices, III-nitride microwave power transistors, III-nitride millimeter wave transistors, III-nitride lateral transistor power switch, III-nitride vertical devices, Physics-Based Modeling, Thermal management in III-nitride HEMT, RF/Microwave applications of III-nitride transistor/wireless power transfer, and more. - Presents a complete review of III-Nitride electronic devices, from fundamental physics, to applications in two key technical areas – RF and power electronics - Outlines fundamentals, reviews state-of-the-art circuits and applications, and introduces current and emerging technologies - Written by a panel of academic and industry experts in each field

Switchmode RF and Microwave Power Amplifiers

Switchmode RF and Microwave Power Amplifiers
Author: Andrei Grebennikov
Publisher: Academic Press
Total Pages: 842
Release: 2021-03-19
Genre: Technology & Engineering
ISBN: 0128227540

Switchmode RF and Microwave Power Amplifiers, Third Edition is an essential reference book on developing RF and microwave switchmode power amplifiers. The book combines theoretical discussions with practical examples, allowing readers to design high-efficiency RF and microwave power amplifiers on different types of bipolar and field-effect transistors, design any type of high-efficiency switchmode power amplifiers operating in Class D or E at lower frequencies and in Class E or F and their subclasses at microwave frequencies with specified output power, also providing techniques on how to design multiband and broadband Doherty amplifiers using different bandwidth extension techniques and implementation technologies. This book provides the necessary information to understand the theory and practical implementation of load-network design techniques based on lumped and transmission-line elements. It brings a unique focus on switchmode RF and microwave power amplifiers that are widely used in cellular/wireless, satellite and radar communication systems which offer major power consumption savings. - Provides a complete history of high-efficiency Class E and Class F techniques - Presents a new chapter on Class E with shunt capacitance and shunt filter to simplify the design of high-efficiency power amplifier with broader frequency bandwidths - Covers different Doherty architectures, including integrated and monolithic implementations, which are and will be, used in modern communication systems to save power consumption and to reduce size and costs - Includes extended coverage of multiband and broadband Doherty amplifiers with different frequency ranges and output powers using different bandwidth extension techniques - Balances theory with practical implementation, avoiding a cookbook approach and enabling engineers to develop better designs, including hybrid, integrated and monolithic implementations

Gallium Nitride (GaN)

Gallium Nitride (GaN)
Author: Farid Medjdoub
Publisher: CRC Press
Total Pages: 372
Release: 2017-12-19
Genre: Technology & Engineering
ISBN: 1482220040

Addresses a Growing Need for High-Power and High-Frequency Transistors Gallium Nitride (GaN): Physics, Devices, and Technology offers a balanced perspective on the state of the art in gallium nitride technology. A semiconductor commonly used in bright light-emitting diodes, GaN can serve as a great alternative to existing devices used in microelectronics. It has a wide band gap and high electron mobility that gives it special properties for applications in optoelectronic, high-power, and high-frequency devices, and because of its high off-state breakdown strength combined with excellent on-state channel conductivity, GaN is an ideal candidate for switching power transistors. Explores Recent Progress in High-Frequency GaN Technology Written by a panel of academic and industry experts from around the globe, this book reviews the advantages of GaN-based material systems suitable for high-frequency, high-power applications. It provides an overview of the semiconductor environment, outlines the fundamental device physics of GaN, and describes GaN materials and device structures that are needed for the next stage of microelectronics and optoelectronics. The book details the development of radio frequency (RF) semiconductor devices and circuits, considers the current challenges that the industry now faces, and examines future trends. In addition, the authors: Propose a design in which multiple LED stacks can be connected in a series using interband tunnel junction (TJ) interconnects Examine GaN technology while in its early stages of high-volume deployment in commercial and military products Consider the potential use of both sunlight and hydrogen as promising and prominent energy sources for this technology Introduce two unique methods, PEC oxidation and vapor cooling condensation methods, for the deposition of high-quality oxide layers A single-source reference for students and professionals, Gallium Nitride (GaN): Physics, Devices, and Technology provides an overall assessment of the semiconductor environment, discusses the potential use of GaN-based technology for RF semiconductor devices, and highlights the current and emerging applications of GaN.