The Experts below are selected from a list of 14634 Experts worldwide ranked by ideXlab platform

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

  • Development of Swept Frequency Method for Measuring Frequency Response of Photodetectors Based on Harmonic Analysis
    IEEE Photonics Technology Letters, 2009
    Co-Authors: Bang Hong Zhang, Jian Hong Ke, Hong Guang Zhang, Wei Li
    Abstract:

    We develop a swept Frequency Method for measuring the Frequency response of photodetectors (PDs) based on harmonic analysis. In this technique, a lightwave from a laser source is modulated by a radio-Frequency (RF) signal via a Mach-Zehnder LiNbO3 modulator, and detected by a PD under test. The measured second-order harmonic of the RF signal contains information of the Frequency responses and nonlinearities of the RF source, modulator, and PD. The Frequency response of the PD alone is obtained by deducting the known Frequency responses and nonlinearities of the RF source and modulator. Compared with the conventional swept Frequency Method, the measurement Frequency range can be doubled using the proposed Method. Experiment results show a good agreement between the measured results and those obtained using other techniques.

Jongsuk Choi - One of the best experts on this subject based on the ideXlab platform.

  • Localization and tracking for simultaneous speakers based on time-Frequency Method and Probability Hypothesis Density filter
    2011 IEEE International Conference on Robotics and Biomimetics, 2011
    Co-Authors: Quang Nguyen, Jongsuk Choi
    Abstract:

    In this paper we present the two steps system of localization and tracking to work in context of simultaneous speakers. The localization algorithm is based on time-Frequency Method which uses an array of three microphones and it enables to locate multiple sound sources in a single time-frame. Localization results with missing detection and clutter are post-processed by the Probability Hypothesis Density (PHD) filter - based tracking algorithm to estimate the smoothed trajectory of each speaker. The experiments carried out on real data recording show that our Method outperforms the multi-target particle filter (MTPF) - based algorithm and is effective in practical application of human-robot interaction.

Pierre Borgnat - One of the best experts on this subject based on the ideXlab platform.

  • A modified time-Frequency Method for testing wide-sense stationarity
    2012 IEEE International Conference on Acoustics Speech and Signal Processing (ICASSP), 2012
    Co-Authors: Douglas Baptista De Souza, Jocelyn Chanussot, Anne-catherine Favre, Pierre Borgnat
    Abstract:

    Recently, a time-Frequency approach for testing stationarity was proposed. However, this Method inefficiently detects nonstationarities of the first-order. Here, we present two contributions that improve the test performance and allow the detection of first-order evolutions. The first one is to use an adequate distance measure. The second is a modification of the Method in order to consider the spectral content from the signal itself when computing the distances.

Bang Hong Zhang - One of the best experts on this subject based on the ideXlab platform.

  • Development of Swept Frequency Method for Measuring Frequency Response of Photodetectors Based on Harmonic Analysis
    IEEE Photonics Technology Letters, 2009
    Co-Authors: Bang Hong Zhang, Jian Hong Ke, Hong Guang Zhang, Wei Li
    Abstract:

    We develop a swept Frequency Method for measuring the Frequency response of photodetectors (PDs) based on harmonic analysis. In this technique, a lightwave from a laser source is modulated by a radio-Frequency (RF) signal via a Mach-Zehnder LiNbO3 modulator, and detected by a PD under test. The measured second-order harmonic of the RF signal contains information of the Frequency responses and nonlinearities of the RF source, modulator, and PD. The Frequency response of the PD alone is obtained by deducting the known Frequency responses and nonlinearities of the RF source and modulator. Compared with the conventional swept Frequency Method, the measurement Frequency range can be doubled using the proposed Method. Experiment results show a good agreement between the measured results and those obtained using other techniques.

Quang Nguyen - One of the best experts on this subject based on the ideXlab platform.

  • Localization and tracking for simultaneous speakers based on time-Frequency Method and Probability Hypothesis Density filter
    2011 IEEE International Conference on Robotics and Biomimetics, 2011
    Co-Authors: Quang Nguyen, Jongsuk Choi
    Abstract:

    In this paper we present the two steps system of localization and tracking to work in context of simultaneous speakers. The localization algorithm is based on time-Frequency Method which uses an array of three microphones and it enables to locate multiple sound sources in a single time-frame. Localization results with missing detection and clutter are post-processed by the Probability Hypothesis Density (PHD) filter - based tracking algorithm to estimate the smoothed trajectory of each speaker. The experiments carried out on real data recording show that our Method outperforms the multi-target particle filter (MTPF) - based algorithm and is effective in practical application of human-robot interaction.