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The NoE TARGET ? success by cooperation
This contribution gives an overview of background, design, working principles, and management issues of some scientific highlights, and of the benefits of the Network of Excellence TARGET (Top Amplifier Research Groups in a European Team).
MRF volume 1 issue 1 Cover and Front matter
High-power monolithic AlGaN/GaN high electron mobility transistor switches
This work presents the design, fabrication, and test of X-band and 2?18 GHz wideband high-power single pole double throw (SPDT) monolithic microwave integrated circuit (MMIC) switches in microstrip gallium nitride (GaN) technology. Such switches have demonstrated state-of-the-art performances and RF fabrication yields better than 65%. In particular, the X-band switch exhibits 1 dB insertion loss,
Implementation of dynamic bias and digital predistortion to enhance efficiency and linearity in a 100 W RF amplifier with OFDM signal
This paper presents a technique that enables both efficiency and linearity enhancements of power amplifiers (PA) used in communication systems. It consists in the implementation of a dynamic bias control combined with digital base-band predistortion. The aim of this paper is to describe a methodology and successive steps of the design procedure to reach optimum performances in terms of power added
Theory and experimental validation of a Class E PA above theoretical maximum frequency
This paper reports an investigation and a proposed solution to design Class E power amplifiers above the theoretical maximum frequency allowed by the adopted active device. Starting from the traditional time domain analysis, a numerical algorithm has been developed and presented in order to extend Class E feasibility through the optimization of the output voltage waveform. A hybrid Class E amplifi
Design considerations for the hot embossing of microstrip antennas on plastic foils
In this contribution, fundamental design considerations for a novel metallization technique to realize millimeter-wave microstrip structures are presented. This hot embossing technology is a fast and economic process originating from the production of three-dimensional molded interconnect devices. Conductive structures are coated onto plastic parts or plastic foils using a heated stamp. This appro
Theoretical performance of reiterated LMMSE filtering and coded radar waveforms
Orthogonal frequency division multiplexing (OFDM) waveforms offer strong advantages for integrated communication and radar systems. However, they exhibit inherent high-range sidelobes after matched filtering when standard communication constellation symbols are used for the coding of the carriers. Consequently, they require filtering at the receiver that can serve for sidelobe suppression in order
Power amplifier optimization using base band and multiharmonic source/load-pull characterization with digital predistortion
In this paper, different techniques are combined in a unique characterization system dedicated to power transistor linearity improvement. Successive optimizations are performed using source-pull/load-pull techniques at fundamental, harmonic, and base-band frequencies associated with an instantaneous memoryless base-band predistortion procedure. Measurement results performed at 1.575 GHz on a metal