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Showing 1 to 16 of 16 for “"RF power amplifier"”.
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New architecture for RF power amplifier linearization
Power amplifier linearization has become an important part of the transmitter system as 3G and developing 4G communication standards require higher linearity than ever before. The thesis proposes two power amplifier linearization solutions : two-point architecture and adaptive digital predistortion …
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RF power amplifier linearity compensation for MRI systems
… linearization system for use with MRI RF power amplifiers was designed and simulated. The design here presented is intended to replace Analogic's (located in Peabody, Massachusetts) feed-forward, digital linearization scheme. This involved the selection and testing of components meeting …
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Digitally-assisted, efficiency enhanced, linear RF power amplifier architectures
… development of efficiency enhanced, linearized power amplifier (PA) architectures. In this research, digital enhancements are used to boost the efficiency of a dual-input LDMOS Doherty PA of 500W peak power. It is shown that the improved phase adjustment and the waveform conditioning for the …
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Broadband RF Power Amplifier Design Methodology Using Sequential Harmonic Characterization
Radio Frequency Power Amplifier (RFPA) amplifies the communication signals to the required power level for transmission. It is the most power consuming stage in a transceiver chain; consequently, any improvement in terms of dissipated power and efficiency of the power amplifier affects the overall …
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A Linear RF Power Amplifier with High Efficiency for Wireless Handsets
… research presents design techniques for a linear power amplifier with high efficiency in wireless handsets. The power amplifier operates with high efficiency at the saturated output power, maintains high linearity with enhanced efficiency at back-off power levels, and covers a broadband frequency …
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The design of a high efficiency RF power amplifier for an MCM process
… arising in the design of a high efficiency RF power amplifier for the Draper Laboratory multi-chip module (MCM) process. A design for a 2.3 GHz PCB amplifier using an enhancement-mode pHEMT device that achieves 68.9% PAE at 30 dBm output power is presented. Analysis of heat management, die …
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Exploring predistortion training algorithms in a Cartesian feedback-trained digital predistortion system for RF power amplifier linearization
… digital predistortion system for RF power amplifier linearization offers many advantages with its combination of two different linearization techniques. This thesis describes such a system, focusing on the important issue of predistorter training. It examines and analyzes in great …
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Design and Linearization of Energy Efficiency Power Amplifier in Nonlinear OFDM Transmitter for LTE-5G Applications. Simulation and measurements of energy efficiency power amplifier in the presence of nonlinear OFDM transmitter system and digital predistortion based on Hammerstein-Wiener method
… to understand a novel line of radio frequency power amplifiers (RFPAs) that address initiatives for efficiency enhancement and linearity compensation to harmonize the fifth generation (5G) campaign. The objective is to enhance the performance of an orthogonal frequency division …
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Techniques for efficient radio frequency power conversion
A diverse range of radio-frequency (RF) power applications demand RF power generation systems that allow for dynamic output power control while having the capability to efficiently deliver power into a varying load. While some of these existing and emerging applications are characterized with …
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Energy-efficient wireless transmitter architecture for mobile multimedia
The continued improvement of transistor performance has increased the limit on the peak energy-efficiency of wireless transmitters. Nevertheless, the average efficiency with mobile multimedia communication is decreasing due to escalating design requirements on linearity and bandwidth. Therefore …
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Design and fabrication of an RF power LDMOSFET on SOI
… (SOI) LDMOSFET technology for RF power amplifier applications. To conduct this study, two generations of SOI RF power devices for portable wireless systems were designed and fabricated. Bulk silicon LDMOSFETs were also made and used as a bench-mark for comparison with the SOI …
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Constant Conduction Angle Biasing for Class C Monolithic RF Power Amplifiers
… faraway user – base stations continually enforce power control. That is, nearby users must lower their transmit power. In CDMA technology, power control can be as large as 70-80dB. At low power outputs, this greatly impacts the performance of the RF power amplifier (PA) in the cellular device. For …
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Analysis and design of ΣΔ Modulators for Radio Frequency Switchmode Power Amplifiers
Power amplifiers are an integral part of every basestation, macrocell, microcell and mobile phone, enabling data to be sent over the distances needed to reach the receiver’s antenna. While linear operation is needed for transmitting WCDMA and OFDM signals, linear operation of a power amplifier is …
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Design and performance of CDMA codes for multiuser communications
Walsh and Gold sequences are fixed power codes and are widely used in multiuser CDMA communications. Their popularity is due to the ease of implementation. Availability of these code sets is limited because of their generating kernels. Emerging radio applications like sensor networks or multiple …
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Linear Power-Efficient RF Amplifier with Partial Positive Feedback
… schemes create signals with high peak-to-average power ratios (PAPR), exhibiting rapid changes in the signal magnitude. To accommodate these high-PAPR signals, RF power amplifiers in mobile devices must operate under backed-off gain conditions, resulting in poor power efficiency. Various …
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Reliability of SiGe HBTs for extreme environment and RF applications
… bipolar transistors (HBTs) under radiofrequency (RF) operation and extreme environments. The degradation of SiGe HBTs due to mixed-mode DC and RF stress has been modeled for the first time. State-of-the-art 200 GHz SiGe HBTs were first characterized, and then DC and RF stressed. Excess base …