The Experts below are selected from a list of 33561 Experts worldwide ranked by ideXlab platform

F Filicori - One of the best experts on this subject based on the ideXlab platform.

  • envelope tracking of an rf High Power Amplifier with an 8 level digitally controlled gan on si supply modulator
    IEEE Transactions on Microwave Theory and Techniques, 2015
    Co-Authors: Corrado Florian, Tommaso Cappello, R P Paganelli, Daniel Niessen, F Filicori
    Abstract:

    This paper presents an envelope tracking (ET) transmitter architecture based on the combination of a novel 3-bit $(N = 3)$ supply modulator and digital predistortion (DPD). The proposed Power converter is based on a direct digital-to-analog conversion architecture that implements the binary-coded sum of $N$ isolated dc voltages, allowing the synthesis of an output waveform with $L = 2^{N}$ voltage levels, with a binary distribution in the range $\Delta V = V_{M} - V_{O}$ (maximum voltage $V_{M}$ , offset voltage $Vo$ ). This solution provides a better voltage resolution $V_{S} = \Delta V/(2^{N}-1)$ with respect to typical multilevel switched-sources topologies $(V_{S} = \Delta V/N)$ . The improved voltage resolution enables the correction of the residual discretization error in the ET transmitter by means of DPD of the RF signal without the need of an auxiliary linear envelope Amplifier. The proposed ET solution has been tested with an L-band 30-W lateral-diffused MOS RF High Power Amplifier (RF HPA) with 1.4- and 10-MHz long-term-evolution signals. In these conditions the converter demonstrated 92% and 83% efficiency, respectively, whereas the congregate efficiency of the transmitter are 38.3% and 23.9% at 5.5 and 1.9 W of average RF output Power, respectively. These performances correspond to an improvement of 17.2 and 17.9 points for the Power-added efficiency of the RF HPA and to 13.4 and 13 points of improvement for the efficiency of the entire transmitter with respect to fixed bias operation.

M Seelmanneggebert - One of the best experts on this subject based on the ideXlab platform.

  • ultra wideband gan mmic chip set and High Power Amplifier module for multi function defense aesa applications
    IEEE Transactions on Microwave Theory and Techniques, 2013
    Co-Authors: Ulf Schmid, P. Schuh, H. Sledzik, Rüdiger Quay, Martin Oppermann, Jorg Schroth, Peter Bruckner, Friedbert Van Raay, M Seelmanneggebert
    Abstract:

    This paper presents measurement results of a monolithic microwave integrated circuit (MMIC) chip set and of an ultra-wideband High Power Amplifier (HPA) transmit module for multi-functional next-generation active electronically scanned antenna radar/electronic warfare/communication applications targeting the frequency range from 6 to 18 GHz. The reported chip set consists of a driver Amplifier (DA) MMIC and an HPA MMIC on a High-Power gallium-nitride process with High electronic-mobility transistors. The DA reaches a Power gain of 11 dB and maximum output Power of 2 W, which is sufficient to drive a final stage in a balanced configuration. The HPA reaches a typical output Power of 12.5 and 10.6 W in pulsed and continuous wave (CW) operation, respectively. Measurements on the module level indicate 18.5-W typical output Power in both pulsed and CW operation.

Corrado Florian - One of the best experts on this subject based on the ideXlab platform.

  • envelope tracking of an rf High Power Amplifier with an 8 level digitally controlled gan on si supply modulator
    IEEE Transactions on Microwave Theory and Techniques, 2015
    Co-Authors: Corrado Florian, Tommaso Cappello, R P Paganelli, Daniel Niessen, F Filicori
    Abstract:

    This paper presents an envelope tracking (ET) transmitter architecture based on the combination of a novel 3-bit $(N = 3)$ supply modulator and digital predistortion (DPD). The proposed Power converter is based on a direct digital-to-analog conversion architecture that implements the binary-coded sum of $N$ isolated dc voltages, allowing the synthesis of an output waveform with $L = 2^{N}$ voltage levels, with a binary distribution in the range $\Delta V = V_{M} - V_{O}$ (maximum voltage $V_{M}$ , offset voltage $Vo$ ). This solution provides a better voltage resolution $V_{S} = \Delta V/(2^{N}-1)$ with respect to typical multilevel switched-sources topologies $(V_{S} = \Delta V/N)$ . The improved voltage resolution enables the correction of the residual discretization error in the ET transmitter by means of DPD of the RF signal without the need of an auxiliary linear envelope Amplifier. The proposed ET solution has been tested with an L-band 30-W lateral-diffused MOS RF High Power Amplifier (RF HPA) with 1.4- and 10-MHz long-term-evolution signals. In these conditions the converter demonstrated 92% and 83% efficiency, respectively, whereas the congregate efficiency of the transmitter are 38.3% and 23.9% at 5.5 and 1.9 W of average RF output Power, respectively. These performances correspond to an improvement of 17.2 and 17.9 points for the Power-added efficiency of the RF HPA and to 13.4 and 13 points of improvement for the efficiency of the entire transmitter with respect to fixed bias operation.

Youngoo Yang - One of the best experts on this subject based on the ideXlab platform.

  • New linearization method for the modulated signals with High peak-to-average ratio: peak-to-average ratio reduction and expansion
    2002 IEEE MTT-S International Microwave Symposium Digest (Cat. No.02CH37278), 2002
    Co-Authors: Youngoo Yang, Jaehyok Yi
    Abstract:

    A new linearization method for the High Power Amplifier modulated by a High peak-to-average ratio signal is proposed. The Amplifier consists of a High Power Amplifier with a predistorter, a peak Power limiter, and cancellation loops similar to the feedforward Amplifier. The linearization performance is enhanced by reducing the peak input Power to the Amplifier using a rate limiter and the distortion from the limited signal is restored at the cancellation sub-path. Simulation and experimental results for the Amplifier module with WCDMA signal show a significant improvement of ACLR.

  • a new empirical large signal model of si ldmosfets for High Power Amplifier design
    IEEE Transactions on Microwave Theory and Techniques, 2001
    Co-Authors: Youngoo Yang, Young Yun Woo, Bumman Kim
    Abstract:

    We propose a new empirical large-signal model of silicon laterally diffused MOSFETs for the design of various modes of High-Power Amplifiers. The new channel current model has only nine parameters that represent the unique operation principles of a MOSFET. In the channel current model, we include the thermal phenomena of High-Power devices. To accurately characterize High-Power devices, we incorporate the channel heating and heat-sink heating effects by providing two thermal capacitances and two thermal resistances. Nonlinear capacitances, including deep subthreshold and triode regions, as well as normal saturation regions, are extracted and modeled. For validation of our model, a 1.4-GHz 5-W Amplifier is implemented, and the measured and simulated results match very well.

Ulf Schmid - One of the best experts on this subject based on the ideXlab platform.

  • ultra wideband gan mmic chip set and High Power Amplifier module for multi function defense aesa applications
    IEEE Transactions on Microwave Theory and Techniques, 2013
    Co-Authors: Ulf Schmid, P. Schuh, H. Sledzik, Rüdiger Quay, Martin Oppermann, Jorg Schroth, Peter Bruckner, Friedbert Van Raay, M Seelmanneggebert
    Abstract:

    This paper presents measurement results of a monolithic microwave integrated circuit (MMIC) chip set and of an ultra-wideband High Power Amplifier (HPA) transmit module for multi-functional next-generation active electronically scanned antenna radar/electronic warfare/communication applications targeting the frequency range from 6 to 18 GHz. The reported chip set consists of a driver Amplifier (DA) MMIC and an HPA MMIC on a High-Power gallium-nitride process with High electronic-mobility transistors. The DA reaches a Power gain of 11 dB and maximum output Power of 2 W, which is sufficient to drive a final stage in a balanced configuration. The HPA reaches a typical output Power of 12.5 and 10.6 W in pulsed and continuous wave (CW) operation, respectively. Measurements on the module level indicate 18.5-W typical output Power in both pulsed and CW operation.