The Experts below are selected from a list of 28041 Experts worldwide ranked by ideXlab platform

J.l. Sudworth - One of the best experts on this subject based on the ideXlab platform.

Mikko Valkama - One of the best experts on this subject based on the ideXlab platform.

  • Decorrelation-based Piecewise Digital Predistortion: Operating Principle and RF Measurements
    2019 16th International Symposium on Wireless Communication Systems (ISWCS), 2019
    Co-Authors: Mahmoud Abdelaziz, Lauri Anttila, Alberto Brihuega, Markus Allen, Mikko Valkama
    Abstract:

    In this paper, we propose a new closed-loop learning architecture for digital predistortion (DPD) with piecewise (PW) memory polynomial models. The technique is targeted specifically for power amplifiers (PAs) that exhibit strong nonlinear behavior and nonlinear memory effects, such as those implemented with gallium nitride (GaN) technology. The learning algorithm is based on a computationally simple decorrelating learning rule, which is applied on each PW polynomial model separately. Measurements with LTE-A signals on a basestation GaN PA show that the proposed technique clearly outperforms the reference closed-loop memory polynomial DPD, in terms of reducing the adjacent channel emissions.

  • Wideband Self-Adaptive RF Cancellation Circuit for Full-Duplex Radio: Operating Principle and Measurements
    2015 IEEE 81st Vehicular Technology Conference (VTC Spring), 2015
    Co-Authors: Timo Huusari, Yang-seok Choi, Petteri Liikkanen, Dani Korpi, Shilpa Talwar, Mikko Valkama
    Abstract:

    This paper presents a novel RF circuit architecture for self-interference cancellation in inband full-duplex radio transceivers . The developed canceller is able to provide wideband cancellation with waveform bandwidths in the order of 100 MHz or beyond and contains also self-adaptive or self-healing features enabling automatic tracking of time-varying self-interference channel characteristics. In addition to architecture and Operating Principle descriptions, we also provide actual RF measurements at 2.4 GHz ISM band demonstrating the achievable cancellation levels with different bandwidths and when Operating in different antenna configurations and under low-cost highly nonlinear power amplifier. In a very challenging example with a 100 MHz waveform bandwidth, around 41 dB total cancellation is obtained while the corresponding cancellation figure is close to 60 dB with the more conventional 20 MHz carrier bandwidth. Also, efficient tracking in time-varying reflection scenarios is demonstrated.

  • VTC Spring - Wideband Self-Adaptive RF Cancellation Circuit for Full-Duplex Radio: Operating Principle and Measurements
    2015 IEEE 81st Vehicular Technology Conference (VTC Spring), 2015
    Co-Authors: Timo Huusari, Yang-seok Choi, Petteri Liikkanen, Dani Korpi, Shilpa Talwar, Mikko Valkama
    Abstract:

    This paper presents a novel RF circuit architecture for self-interference cancellation in inband full-duplex radio transceivers . The developed canceller is able to provide wideband cancellation with waveform bandwidths in the order of 100 MHz or beyond and contains also self-adaptive or self-healing features enabling automatic tracking of time-varying self-interference channel characteristics. In addition to architecture and Operating Principle descriptions, we also provide actual RF measurements at 2.4 GHz ISM band demonstrating the achievable cancellation levels with different bandwidths and when Operating in different antenna configurations and under low-cost highly nonlinear power amplifier. In a very challenging example with a 100 MHz waveform bandwidth, around 41 dB total cancellation is obtained while the corresponding cancellation figure is close to 60 dB with the more conventional 20 MHz carrier bandwidth. Also, efficient tracking in time-varying reflection scenarios is demonstrated.

Joan Nicolas-apruzzese - One of the best experts on this subject based on the ideXlab platform.

  • A Multilevel Active-Clamped Converter Topology—Operating Principle
    IEEE Transactions on Industrial Electronics, 2011
    Co-Authors: Sergio Busquets-monge, Joan Nicolas-apruzzese
    Abstract:

    This paper presents a novel multilevel active-clamped converter topology, which is an extension to m levels of the three-level active neutral-point-clamped topology. The Operating Principle is established through the definition of a proper set of switching states and a transition strategy between adjacent switching states. The benefits of the proposed converter topology and control in comparison to alternative multilevel converter topologies are discussed. The simulation and experimental results of a simple four-level dc-dc converter configuration are presented to illustrate the converter performance features. The experimental results of a four-level three-phase dc-ac converter are also presented to further validate the proposed topology and Operating Principle.

  • An m-level active-clamped converter topology - Operating Principle
    2010 IEEE International Symposium on Industrial Electronics, 2010
    Co-Authors: Sergio Busquets-monge, Joan Nicolas-apruzzese
    Abstract:

    This paper presents a novel multilevel active-clamped converter topology, which is an extension to m levels of the three-level active neutral-point-clamped topology. The Operating Principle is established through the definition of a proper set of switching states and a transition strategy between adjacent switching states. The benefits of the proposed converter topology and control in comparison to alternative multilevel converter topologies are discussed. Simulation results of a simple dc-dc converter configuration are presented to illustrate the converter performance features.

Joan Nicolasapruzzese - One of the best experts on this subject based on the ideXlab platform.

  • a multilevel active clamped converter topology Operating Principle
    IEEE Transactions on Industrial Electronics, 2011
    Co-Authors: S Busquetsmonge, Joan Nicolasapruzzese
    Abstract:

    This paper presents a novel multilevel active-clamped converter topology, which is an extension to m levels of the three-level active neutral-point-clamped topology. The Operating Principle is established through the definition of a proper set of switching states and a transition strategy between adjacent switching states. The benefits of the proposed converter topology and control in comparison to alternative multilevel converter topologies are discussed. The simulation and experimental results of a simple four-level dc-dc converter configuration are presented to illustrate the converter performance features. The experimental results of a four-level three-phase dc-ac converter are also presented to further validate the proposed topology and Operating Principle.

Timo Huusari - One of the best experts on this subject based on the ideXlab platform.

  • Wideband Self-Adaptive RF Cancellation Circuit for Full-Duplex Radio: Operating Principle and Measurements
    2015 IEEE 81st Vehicular Technology Conference (VTC Spring), 2015
    Co-Authors: Timo Huusari, Yang-seok Choi, Petteri Liikkanen, Dani Korpi, Shilpa Talwar, Mikko Valkama
    Abstract:

    This paper presents a novel RF circuit architecture for self-interference cancellation in inband full-duplex radio transceivers . The developed canceller is able to provide wideband cancellation with waveform bandwidths in the order of 100 MHz or beyond and contains also self-adaptive or self-healing features enabling automatic tracking of time-varying self-interference channel characteristics. In addition to architecture and Operating Principle descriptions, we also provide actual RF measurements at 2.4 GHz ISM band demonstrating the achievable cancellation levels with different bandwidths and when Operating in different antenna configurations and under low-cost highly nonlinear power amplifier. In a very challenging example with a 100 MHz waveform bandwidth, around 41 dB total cancellation is obtained while the corresponding cancellation figure is close to 60 dB with the more conventional 20 MHz carrier bandwidth. Also, efficient tracking in time-varying reflection scenarios is demonstrated.

  • VTC Spring - Wideband Self-Adaptive RF Cancellation Circuit for Full-Duplex Radio: Operating Principle and Measurements
    2015 IEEE 81st Vehicular Technology Conference (VTC Spring), 2015
    Co-Authors: Timo Huusari, Yang-seok Choi, Petteri Liikkanen, Dani Korpi, Shilpa Talwar, Mikko Valkama
    Abstract:

    This paper presents a novel RF circuit architecture for self-interference cancellation in inband full-duplex radio transceivers . The developed canceller is able to provide wideband cancellation with waveform bandwidths in the order of 100 MHz or beyond and contains also self-adaptive or self-healing features enabling automatic tracking of time-varying self-interference channel characteristics. In addition to architecture and Operating Principle descriptions, we also provide actual RF measurements at 2.4 GHz ISM band demonstrating the achievable cancellation levels with different bandwidths and when Operating in different antenna configurations and under low-cost highly nonlinear power amplifier. In a very challenging example with a 100 MHz waveform bandwidth, around 41 dB total cancellation is obtained while the corresponding cancellation figure is close to 60 dB with the more conventional 20 MHz carrier bandwidth. Also, efficient tracking in time-varying reflection scenarios is demonstrated.