The Experts below are selected from a list of 75 Experts worldwide ranked by ideXlab platform

Bin Li - One of the best experts on this subject based on the ideXlab platform.

  • study of the mechanism and suppression of group Delay Distortion of a traveling wave tube using eulerian hydrodynamic analysis
    IEEE Transactions on Electron Devices, 2018
    Co-Authors: Yulu Hu, Quan Hu, Bin Li
    Abstract:

    In this paper, a simplified Eulerian nonlinear beam-wave interaction (BWI) theory of a helix traveling-wave tube (TWT) is developed. Derived from this model, analytic solutions are first obtained by the method of successive approximation. Then, the linear analytic solution of group Delay Distortion (GDD) is obtained. Subsequently, the mechanism of group Delay is studied. It is found that the main mechanism of GDD is the propagation time difference between the wave group and electron beam throughout the BWI region. Furthermore, a series of group Delay suppression schemes is discussed by using the mechanism. Finally, the Eulerian formation and the suppression schemes are validated by an in-house code based on the Lagrangian theory. Results show that the analytic solutions of Eulerian model and GDD agree well with the Lagrangian theory in small-signal region. In addition, the suppression schemes are applied to a high-efficiency Ku-band space TWT. The GDD is greatly reduced by approximately 50% with a slightly drop of output power.

Yulu Hu - One of the best experts on this subject based on the ideXlab platform.

  • study of the mechanism and suppression of group Delay Distortion of a traveling wave tube using eulerian hydrodynamic analysis
    IEEE Transactions on Electron Devices, 2018
    Co-Authors: Yulu Hu, Quan Hu, Bin Li
    Abstract:

    In this paper, a simplified Eulerian nonlinear beam-wave interaction (BWI) theory of a helix traveling-wave tube (TWT) is developed. Derived from this model, analytic solutions are first obtained by the method of successive approximation. Then, the linear analytic solution of group Delay Distortion (GDD) is obtained. Subsequently, the mechanism of group Delay is studied. It is found that the main mechanism of GDD is the propagation time difference between the wave group and electron beam throughout the BWI region. Furthermore, a series of group Delay suppression schemes is discussed by using the mechanism. Finally, the Eulerian formation and the suppression schemes are validated by an in-house code based on the Lagrangian theory. Results show that the analytic solutions of Eulerian model and GDD agree well with the Lagrangian theory in small-signal region. In addition, the suppression schemes are applied to a high-efficiency Ku-band space TWT. The GDD is greatly reduced by approximately 50% with a slightly drop of output power.

Quan Hu - One of the best experts on this subject based on the ideXlab platform.

  • study of the mechanism and suppression of group Delay Distortion of a traveling wave tube using eulerian hydrodynamic analysis
    IEEE Transactions on Electron Devices, 2018
    Co-Authors: Yulu Hu, Quan Hu, Bin Li
    Abstract:

    In this paper, a simplified Eulerian nonlinear beam-wave interaction (BWI) theory of a helix traveling-wave tube (TWT) is developed. Derived from this model, analytic solutions are first obtained by the method of successive approximation. Then, the linear analytic solution of group Delay Distortion (GDD) is obtained. Subsequently, the mechanism of group Delay is studied. It is found that the main mechanism of GDD is the propagation time difference between the wave group and electron beam throughout the BWI region. Furthermore, a series of group Delay suppression schemes is discussed by using the mechanism. Finally, the Eulerian formation and the suppression schemes are validated by an in-house code based on the Lagrangian theory. Results show that the analytic solutions of Eulerian model and GDD agree well with the Lagrangian theory in small-signal region. In addition, the suppression schemes are applied to a high-efficiency Ku-band space TWT. The GDD is greatly reduced by approximately 50% with a slightly drop of output power.

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

  • analysis of the group Delay Distortion in traveling wave tubes
    International Vacuum Electronics Conference, 2015
    Co-Authors: Haijian Qiu, Zhonghai Yang
    Abstract:

    An analysis of the group Delay (GD) Distortion in helix Traveling-Wave tubes (TWTs) is described. Two reasons causing the GD Distortion are put forward. One reason is slow wave structure (SWS) dispersion. The second one is caused by beam-wave interaction (BWI). These two dispersions are carefully designed to suppress the GD Distortion in linear and nonlinear beam-wave region respectively. Also the BWI dispersions in linear and nonlinear beam-wave regions are improved in theory respectively.

  • the study of group Delay Distortion in helix twt
    International Vacuum Electronics Conference, 2014
    Co-Authors: Haijian Qiu, Zhonghai Yang
    Abstract:

    The group Delay has been simulated and optimized in a high efficiency Ku-band Helix TWT with Microwave Tube Simulation Suite (MTSS). The results of the simulation and optimization show that the first segment of the pitch (p 0 ) and the working voltage (V) play a significant role in affecting group Delay. And the group Delay has been reduced by 1.14 ns after optimization.

Shan Qiao - One of the best experts on this subject based on the ideXlab platform.

  • simulation study on compensating group Delay Distortion based on material dispersion
    2017 International Applied Computational Electromagnetics Society Symposium (ACES), 2017
    Co-Authors: Chun Wang, Anjie Zhu, Zhongbo Zhu, Shan Qiao
    Abstract:

    In this study, we investigate the group Delay Distortion of a signal due to the presence of dispersion in transmission systems, and propose an approach to eliminate the Distortion by dispersion compensation based on engineered material dispersion. We demonstrate that utilizing the anomalous frequency response of a dispersive material, envelope Distortion of a signal passing through a given transmission system can be compensated, theoretical analysis and full-wave simulation agreeing well with each other.

  • compensating group Delay Distortion of signals based on engineered material dispersion
    AIP Advances, 2017
    Co-Authors: Chun Wang, Zhongbo Zhu, Cheng Cao, Shan Qiao
    Abstract:

    Dispersion, which originates from the total frequency responses of materials, devices and transmission lines, makes envelope Distortion of signals inevitable in transmission systems. In this study, we investigate the group Delay Distortion of a signal due to the presence of dispersion in transmission systems, and propose an approach to eliminate the Distortion by compensation based on engineered material dispersion. We demonstrate theoretically and experimentally that utilizing the anomalous frequency response of a dispersive material, envelope Distortion of a signal passing through a given transmission system can be fully compensated. Compared with previous researches on dispersion compensation using grating compressors or chirp compressors in optics and non-Foster circuits in microwave bands, the proposed approach is robust and scalable to other frequency bands.