Performance Improvement of Optical Multiple Access CDMA Network Using a New Three-Dimensional (Spectral/Time/Spatial) Code

Wireless Personal Communications - In this paper, a novel code named three dimensional single weight zero cross correlation (3D-SWZCC) code has been developed for spectral/time/spatial (S/T/S)...     

Reduced reference image quality assessment based on statistics in empirical mode decomposition domain

This paper deals with the image quality assessment (IQA) task using a natural image statistics approach. A reduced reference (RRIQA) measure based on the bidimensional empirical mode decomposition is introduced. First, we decompose both, reference and distorted images, into intrinsic mode functions (IMF) and then we use the generalized Gaussian density (GGD) to model IMF coefficients of the reference image. Finally, we measure the impairment of a distorted image by fitting error between the IMF coefficients histogram of the distorted image and the estimated IMF coefficients distribution of the reference image, using the Kullback–Leibler divergence (KLD). Furthermore, to predict the quality, we propose a new support vector machine-based (SVM) classification approach as an alternative to logistic function-based regression. In order to validate the proposed measure, three benchmark datasets are involved in our experiments. Results demonstrate that the proposed metric compare favorably with alternative solutions for a wide range of degradation encountered in practical situations.     

GaAs Oxide Desorption under Extreme Ultraviolet Photon Flux

The interaction of light with matter is one of the most studied branches of modern physics. Beyond its scientific interest, the technological impact is enormous, from optoelectronics to miniaturization in integrated circuits. In the latter case, in order to produce even smaller circuits, the introduction of a lithographic technology based on extreme ultraviolet (EUV) light is forecast for the year 2007. This introduces a number of open issues regarding the interaction of EUV radiation with matter. Herein, we report an unexpectedly strong desorption effect due to the irradiation of a nanopatterned gallium arsenide oxide with EUV light. The observed phenomenon can be explained in the framework of Auger‐assisted desorption, with the size of the effect justified by the particular photon wavelength, in the EUV region, and the extremely high photon flux. The mechanism behind the observed phenomena will also apply to other semiconductors, and we believe that our findings will have an impact on the development of EUV lithography.