The Experts below are selected from a list of 312 Experts worldwide ranked by ideXlab platform

E. Mossberg - One of the best experts on this subject based on the ideXlab platform.

  • Estimation for Power control of large-scale fading channels from irregularly sampled noisy data
    2006 American Control Conference, 2006
    Co-Authors: M. Mossberg, E.k. Larsson, E. Mossberg
    Abstract:

    A stochastic differential equation is used for describing the Power Attenuation dynamics for large-scale log-normal fading channels in wireless communication systems. Fast and robust instrumental variable type estimators for the model parameters from irregularly sampled data affected by measurement noise are given. The Cramer-Rao bound for the estimation of the model parameters is derived, and the qualities of the proposed estimators are evaluated with respect to the bound. A brief study of Power control is also given

  • Fast estimators for large-scale fading channels from irregularly sampled data
    IEEE Transactions on Signal Processing, 2006
    Co-Authors: M. Mossberg, E.k. Larsson, E. Mossberg
    Abstract:

    The problem of estimating the Power Attenuation dynamics for large-scale lognormal fading channels in wireless communication systems, when the model is described as a mean reverting Ornstein-Uhlenbeck process, is studied in the paper. Fast and accurate estimators for the model parameters from irregularly sampled data are suggested for both offline and online applications. The Crameacuter-Rao bound for the estimation of the model parameters is derived, and the qualities of the proposed estimators are evaluated with respect to the bound

  • Estimation of large-scale fading channels from sample covariances
    Proceedings of the 45th IEEE Conference on Decision and Control, 2006
    Co-Authors: M. Mossberg, E.k. Larsson, E. Mossberg
    Abstract:

    A stochastic differential equation is considered for modeling the Power Attenuation dynamics for large-scale lognormal fading channels in wireless communication systems. The model can be used for Power control and the problem of estimating the model parameters is studied. Estimators for the parameters based on sample covariances from data corrupted by discrete-time measurement noise are given. The qualities of the estimators are illustrated in a numerical study and the empirical variances are close to the Cramer-Rao bound

H Y Zahran - One of the best experts on this subject based on the ideXlab platform.

  • facile design of a cut off laser Power Attenuation using safranin o doped pmma polymeric composite films optical spectroscopy and dielectric properties
    Optik, 2020
    Co-Authors: Yasmin Khairy, I S Yahia, H Y Zahran
    Abstract:

    Abstract Polymethyl methacrylate with Safranin O dye samples has been prepared using the several-weight percentage of the dye varying from 0.185 to 7.407 wt % of Safranin O. We have examined their structure, optical, dielectric and optical limiting properties. The preparation has been done utilizing a fast and simple method, casting technique, where both the polymer and the dye were solved in chloroform. The characterization of the structure has been achieved using XRD where the polymeric composites samples displayed a noncrystalline hump that supports the amorphous structure of the studied films. Spectroscopy measurements have been exhausted to approximate the spectral absorption estimations of the samples like absorbance, transmittance as well as the calculations of the index of absorption (k), and optical transition bandgap (Eg). The results indicate that the optical parameters alter by increasing the concentrations of the doping dye. From the obtained values of Eg, two optical transitions (direct and indirect) are possible for these composites. According to the applied models in the polymeric materials field, dielectric characterizations have been done and their parameters have been measured. We have studied the optical limiting characteristics of the samples with several concentrations of the dye using different laser sources of He–Ne working at 632.8 nm and 533 nm. The result showed an evident optical limiting impact on the films. Utilizing this optical limiting impact, the samples under consideration are appropriate to be applied in the applications of solar cell and CUT-OFF laser filters and laser Power Attenuation.

  • optical analysis of nanostructured rose bengal thin films using kramers kronig approach new trend in laser Power Attenuation
    Optics and Laser Technology, 2019
    Co-Authors: Aslam M Manthrammel, I S Yahia, H Y Zahran, A M Aboraia, Mohd Shkir, Mohammed A Assiri
    Abstract:

    Abstract Highly stable Rose Bengal (RsB) organic semiconductor thin films were deposited on glass substrates with different thicknesses ranging from 95 to 325 nm. Optical transmission, reflection, and absorption studies were employed to analyze various optical constants. Refractive index and extinction coefficient values were attained using Kramers-Kronig calculations from the reflectance data. Dielectric constant, loss and dissipation factor were studied. Third-order nonlinear optical susceptibility and refractive index values were estimated using linear refractive index and absorption coefficient data for RsB films and studied their properties in nonlinear media. Optical limiting characteristics are found to be enhanced by increasing the thicknesses of films. The studied films can be used to limit the laser Power of wavelengths 632 nm and 532 nm as an optical limiting material. The present work suggests that film of RsB is a promising candidate for wide-scale optoelectronic applications including IR pass filter, laser Power Attenuation, and selective CUT-OFF laser filters in the wavelength range 490–595 nm.

  • Optical analysis of nanostructured rose bengal thin films using Kramers–Kronig approach: New trend in laser Power Attenuation
    Optics and Laser Technology, 2019
    Co-Authors: M. Aslam Manthrammel, I S Yahia, H Y Zahran, A M Aboraia, Mohd Shkir, Mohammed A Assiri, V. Ganesh, S. Alfaify, Alexander V. Soldatov
    Abstract:

    Abstract Highly stable Rose Bengal (RsB) organic semiconductor thin films were deposited on glass substrates with different thicknesses ranging from 95 to 325 nm. Optical transmission, reflection, and absorption studies were employed to analyze various optical constants. Refractive index and extinction coefficient values were attained using Kramers-Kronig calculations from the reflectance data. Dielectric constant, loss and dissipation factor were studied. Third-order nonlinear optical susceptibility and refractive index values were estimated using linear refractive index and absorption coefficient data for RsB films and studied their properties in nonlinear media. Optical limiting characteristics are found to be enhanced by increasing the thicknesses of films. The studied films can be used to limit the laser Power of wavelengths 632 nm and 532 nm as an optical limiting material. The present work suggests that film of RsB is a promising candidate for wide-scale optoelectronic applications including IR pass filter, laser Power Attenuation, and selective CUT-OFF laser filters in the wavelength range 490–595 nm.

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

  • Estimation for Power control of large-scale fading channels from irregularly sampled noisy data
    2006 American Control Conference, 2006
    Co-Authors: M. Mossberg, E.k. Larsson, E. Mossberg
    Abstract:

    A stochastic differential equation is used for describing the Power Attenuation dynamics for large-scale log-normal fading channels in wireless communication systems. Fast and robust instrumental variable type estimators for the model parameters from irregularly sampled data affected by measurement noise are given. The Cramer-Rao bound for the estimation of the model parameters is derived, and the qualities of the proposed estimators are evaluated with respect to the bound. A brief study of Power control is also given

  • Fast estimators for large-scale fading channels from irregularly sampled data
    IEEE Transactions on Signal Processing, 2006
    Co-Authors: M. Mossberg, E.k. Larsson, E. Mossberg
    Abstract:

    The problem of estimating the Power Attenuation dynamics for large-scale lognormal fading channels in wireless communication systems, when the model is described as a mean reverting Ornstein-Uhlenbeck process, is studied in the paper. Fast and accurate estimators for the model parameters from irregularly sampled data are suggested for both offline and online applications. The Crameacuter-Rao bound for the estimation of the model parameters is derived, and the qualities of the proposed estimators are evaluated with respect to the bound

  • Estimation of large-scale fading channels from sample covariances
    Proceedings of the 45th IEEE Conference on Decision and Control, 2006
    Co-Authors: M. Mossberg, E.k. Larsson, E. Mossberg
    Abstract:

    A stochastic differential equation is considered for modeling the Power Attenuation dynamics for large-scale lognormal fading channels in wireless communication systems. The model can be used for Power control and the problem of estimating the model parameters is studied. Estimators for the parameters based on sample covariances from data corrupted by discrete-time measurement noise are given. The qualities of the estimators are illustrated in a numerical study and the empirical variances are close to the Cramer-Rao bound

I S Yahia - One of the best experts on this subject based on the ideXlab platform.

  • facile design of a cut off laser Power Attenuation using safranin o doped pmma polymeric composite films optical spectroscopy and dielectric properties
    Optik, 2020
    Co-Authors: Yasmin Khairy, I S Yahia, H Y Zahran
    Abstract:

    Abstract Polymethyl methacrylate with Safranin O dye samples has been prepared using the several-weight percentage of the dye varying from 0.185 to 7.407 wt % of Safranin O. We have examined their structure, optical, dielectric and optical limiting properties. The preparation has been done utilizing a fast and simple method, casting technique, where both the polymer and the dye were solved in chloroform. The characterization of the structure has been achieved using XRD where the polymeric composites samples displayed a noncrystalline hump that supports the amorphous structure of the studied films. Spectroscopy measurements have been exhausted to approximate the spectral absorption estimations of the samples like absorbance, transmittance as well as the calculations of the index of absorption (k), and optical transition bandgap (Eg). The results indicate that the optical parameters alter by increasing the concentrations of the doping dye. From the obtained values of Eg, two optical transitions (direct and indirect) are possible for these composites. According to the applied models in the polymeric materials field, dielectric characterizations have been done and their parameters have been measured. We have studied the optical limiting characteristics of the samples with several concentrations of the dye using different laser sources of He–Ne working at 632.8 nm and 533 nm. The result showed an evident optical limiting impact on the films. Utilizing this optical limiting impact, the samples under consideration are appropriate to be applied in the applications of solar cell and CUT-OFF laser filters and laser Power Attenuation.

  • optical analysis of nanostructured rose bengal thin films using kramers kronig approach new trend in laser Power Attenuation
    Optics and Laser Technology, 2019
    Co-Authors: Aslam M Manthrammel, I S Yahia, H Y Zahran, A M Aboraia, Mohd Shkir, Mohammed A Assiri
    Abstract:

    Abstract Highly stable Rose Bengal (RsB) organic semiconductor thin films were deposited on glass substrates with different thicknesses ranging from 95 to 325 nm. Optical transmission, reflection, and absorption studies were employed to analyze various optical constants. Refractive index and extinction coefficient values were attained using Kramers-Kronig calculations from the reflectance data. Dielectric constant, loss and dissipation factor were studied. Third-order nonlinear optical susceptibility and refractive index values were estimated using linear refractive index and absorption coefficient data for RsB films and studied their properties in nonlinear media. Optical limiting characteristics are found to be enhanced by increasing the thicknesses of films. The studied films can be used to limit the laser Power of wavelengths 632 nm and 532 nm as an optical limiting material. The present work suggests that film of RsB is a promising candidate for wide-scale optoelectronic applications including IR pass filter, laser Power Attenuation, and selective CUT-OFF laser filters in the wavelength range 490–595 nm.

  • Optical analysis of nanostructured rose bengal thin films using Kramers–Kronig approach: New trend in laser Power Attenuation
    Optics and Laser Technology, 2019
    Co-Authors: M. Aslam Manthrammel, I S Yahia, H Y Zahran, A M Aboraia, Mohd Shkir, Mohammed A Assiri, V. Ganesh, S. Alfaify, Alexander V. Soldatov
    Abstract:

    Abstract Highly stable Rose Bengal (RsB) organic semiconductor thin films were deposited on glass substrates with different thicknesses ranging from 95 to 325 nm. Optical transmission, reflection, and absorption studies were employed to analyze various optical constants. Refractive index and extinction coefficient values were attained using Kramers-Kronig calculations from the reflectance data. Dielectric constant, loss and dissipation factor were studied. Third-order nonlinear optical susceptibility and refractive index values were estimated using linear refractive index and absorption coefficient data for RsB films and studied their properties in nonlinear media. Optical limiting characteristics are found to be enhanced by increasing the thicknesses of films. The studied films can be used to limit the laser Power of wavelengths 632 nm and 532 nm as an optical limiting material. The present work suggests that film of RsB is a promising candidate for wide-scale optoelectronic applications including IR pass filter, laser Power Attenuation, and selective CUT-OFF laser filters in the wavelength range 490–595 nm.

E.k. Larsson - One of the best experts on this subject based on the ideXlab platform.

  • Estimation for Power control of large-scale fading channels from irregularly sampled noisy data
    2006 American Control Conference, 2006
    Co-Authors: M. Mossberg, E.k. Larsson, E. Mossberg
    Abstract:

    A stochastic differential equation is used for describing the Power Attenuation dynamics for large-scale log-normal fading channels in wireless communication systems. Fast and robust instrumental variable type estimators for the model parameters from irregularly sampled data affected by measurement noise are given. The Cramer-Rao bound for the estimation of the model parameters is derived, and the qualities of the proposed estimators are evaluated with respect to the bound. A brief study of Power control is also given

  • Fast estimators for large-scale fading channels from irregularly sampled data
    IEEE Transactions on Signal Processing, 2006
    Co-Authors: M. Mossberg, E.k. Larsson, E. Mossberg
    Abstract:

    The problem of estimating the Power Attenuation dynamics for large-scale lognormal fading channels in wireless communication systems, when the model is described as a mean reverting Ornstein-Uhlenbeck process, is studied in the paper. Fast and accurate estimators for the model parameters from irregularly sampled data are suggested for both offline and online applications. The Crameacuter-Rao bound for the estimation of the model parameters is derived, and the qualities of the proposed estimators are evaluated with respect to the bound

  • Estimation of large-scale fading channels from sample covariances
    Proceedings of the 45th IEEE Conference on Decision and Control, 2006
    Co-Authors: M. Mossberg, E.k. Larsson, E. Mossberg
    Abstract:

    A stochastic differential equation is considered for modeling the Power Attenuation dynamics for large-scale lognormal fading channels in wireless communication systems. The model can be used for Power control and the problem of estimating the model parameters is studied. Estimators for the parameters based on sample covariances from data corrupted by discrete-time measurement noise are given. The qualities of the estimators are illustrated in a numerical study and the empirical variances are close to the Cramer-Rao bound