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71.
A new scheme, based on Bragg gratings written in highly birefringent fibre that allows both increasing the channel density and relaxing the filter bandwidth requirements in future radio-over-fibre wavelength interleaved distribution networks, is presented and tested.  相似文献   
72.
基于重叠正交变换的自适应图像水印   总被引:1,自引:0,他引:1  
刘宇新  李衍达 《电子学报》2001,29(10):1368-1372
本文提出了一种基于重叠正交变换(LOT)的自适应图像水印算法,给出了水印嵌簇检测的详细算法设计,数字图像水印是最近发展起来的一项新技术,它为图像的版权保护问题提供了一种新的解决思路,本文首次在水印算法中采用了LOT以代替传统的离散余弦变换(DCT),从而有效地避免了DCT的块效应,同时,本文还利用人的视觉系统(HVS)特性,在对图像块进行分类的基础上完成水印的自适应嵌入,实验结果表明,本文所提出的图像水印算法有效地提高了水印的鲁棒性和透明性。  相似文献   
73.
有机半导体激光器实现了从光泵浦到电泵浦。回顾了有机半导体激光器从光泵浦到电流入的发展过程。概述了有机半导体材料产生激光的特性,介绍了贝尔实验室第一个有机固态电注入型激光器的工作原理,提出了在器件结构上的一些新设想。  相似文献   
74.
This work describes a one-step separation of rat tissue phospholipid classes by high-performance liquid chromatography (HPLC) using a silica column and a new light-scattering detector (LSD). Complete separation of phosphatidylcholine, phosphatidylethanolamine, diphosphatidylglycerol, phosphatidylinositol, phosphatidylserine, sphingomyelin, lysophosphatidylethanolamine, and lysophosphatidylcholine was obtained. Direct quantification was achieved after detector calibration for each phospholipid class. The detector response was shown to be linear within the ranges used. The LSD results agreed well with those obtained by phospholipid phosphorus assay. The present method was applied to rat heart and rat liver phospholipid analysis.  相似文献   
75.
Wireless Networks - D2D (device-to-device) communication is one of the developments of 5G networks (5th generation mobile networks) that reduce mobile traffic load, reduce energy consumption and...  相似文献   
76.
A method to compute the monostatic radar cross section (RCS) of complex bodies modeled by nonuniform rational B-spline (NURBS) surfaces is presented. The bodies can be covered by any kind of radar absorbing material (RAM) with electric and/or magnetic losses. Physical optics (PO) is used to obtain the scattered field of each surface. Fresnel coefficients are included in the stationary phase method (SPM) in order to take into account the effect of the RAM material. The contribution of diffraction by edges and double effects is also considered, improving the results of the PO approach. The diffraction is computed by the equivalent current method (ECM). A combination of geometrical optics (GO) with PO and ECM is used for the double reflection and double interaction between edges and surfaces respectively. Some simple cases are shown to validate the proposed method. The reliability of the method to analyzing the effect of covering a realistic target with RAM is also illustrated.  相似文献   
77.
Despite the great advances in the theory and applications of fractional calculus, some topics remain unclear, making a systematic use difficult. In this paper, the fractional differintegration definition problem is studied from a systems point of view. Both local (Grunwald-Letnikov) and global (convolutional) definitions are considered. It is shown that the Cauchy formulation should be adopted since it is coherent with usual practice in signal processing and control applications.  相似文献   
78.
This paper presents a method for extracting, in the digital domain, the main characteristic parameters of an analog sine-wave signal. It is based on a double-modulation, square-wave and sigma-delta, together with a simple Digital Processing Algorithm. It leads to an efficient and robust approach very suitable for BIST applications. In this line, some considerations for on-chip implementation are addressed together with simulation results that validate the feasibility of the proposed approach.Diego Vázquez was born in El Coronil, Sevilla, Spain, in 1966. He received the Licenciado en Física degree in 1989 and the Doctor en Ciencias Físicas degree in 1995, both from the University of Sevilla, Spain. Since 1990, he has been with the Departamento de Electrónica y Electromagnetismo, University of Sevilla, where he is a Associate Professor, and also with the Instituto de Microelectrónica de Sevilla, Centro Nacional de Microelectrónica (IMSE-CNM-CSIC), Sevilla, Spain. He has published about 100 papers in international journals, books and major conferences. In 1992 he won the Best Paper Award of the 10th IEEE VLSI Test Symposium. His research interests are in the fields of design, fault tolerance, test, and design for testability of analog and mixed-signal circuits.Gloria Huertas was born in Sevilla, Spain, in 1974. She received the Licenciado en Física degree in 1997 and the Ph.D. in 2004, both from the University of Sevilla, Spain. Since then, she has been with the Departamento de Electrónica y Electromagnetismo, University of Sevilla, where she is Assistant Professor, and also with the Instituto de Microelectrónica de Sevilla, Centro Nacional de Microelectrónica (IMSE-CNM-CSIC), Sevilla, Spain. Her research focuses on designing electronic mixed-signal circuits and systems including techniques for testability.África Luque was born in Zamora (Spain) in 1977. She received the Licenciado en Física degree in 2000 from the University of Sevilla, Sevilla, Spain. She is with the Departamento de Electrónica y Electromagnetismo, University of Sevilla, and also with the Instituto de Microelectrónica de Sevilla, Centro Nacional de Microelectrónica (IMSE-CNM-CSIC), Sevilla, Spain, where she is currently pursuing the Ph.D. degree. Her research focuses on the design and test of mixed-signal circuits including Silicon-On-Insulator technologies.Manuel J. Barragan was born in Sevilla, Spain, in 1980. He received the Licenciado en Física degree in 2003 from the University of Sevilla, Sevilla, Spain. He is currently pursuing the Ph.D. degree from the Instituto de Microelectrónica de Sevilla (IMSE, CNM) on the topics of test and design for testability of analog and mixed-signal circuits.Gildas Leger was born in St. Brieuc, Côtes dArmor, France, in 1976. He received the Ingénieur en Physique degree in 1999 from the National Institute of Applied Sciences (INSA) of Rennes, France.He is currently pursuing the Ph.D. degree from the Instituto de Microelectrónica de Sevilla (IMSE, CNM). His research focuses on designing electronic mixed-signal circuits and systems including techniques for testability, specially in the domain of analog to digital conversion.Adoración Rueda joined the Department of Electronics and Electromagnetism at the University of Seville in 1976 as Assistant Professor, and obtained the Ph.D. degree in 1982. From 1984 to 1996 she was Associate Professor in that Department, where now holds the position of Full Professor in Electronics. In 1989 she became researcher at the Department of Analog Design of the National Microelectronics Center (CNM), now Institute of Microelectronics at Seville (IMSE).She has participated in several research projects financed by the Spanish CICYT and by different programs of the European Community. She has published about 135 papers in international journals, books and major conferences. In 1992 she won the Best Paper Award of the 10th IEEE VLSI Test Symposium. Her research interests are currently focused on the topics of Design and Test of Analog and Mixed-signal Circuits, Behavioral Modeling of Mixed-signal Circuits, and development of CAD tools.Jose Luis Huertas received the Licenciado en Física degree nd the Doctor en Ciencias Físicas degrees in 1969 and 1973, respectively, both from the University of Sevilla, Spain.From 1970 to 1971, he was with the Philips International Institute, Eindhoven, The Netherlands, as a postgraduate student. Since 1971, he has been with the Departamento de Electrónica y Electromagnetismo, University of Sevilla, Spain, where he is a Full Professor. He is also the Director of the Instituto de Microelectrónica de Sevilla, Centro Nacional de Microelectrónica de Sevilla, Seville, Spain. His current interests include the design and testing of analog/digital integrated circuits, computer-aided IC analysis and design, fuzzy logic, nonlinear microelectronics, and neural networks.  相似文献   
79.
A dual-band CMOS low-noise amplifier with inductor magnetic coupling and current steering is presented which avoids the use of switches in the signal path, and has the possibility of controlling the voltage gain in the two bands, without disturbing the input impedance matching.  相似文献   
80.
I^2C总线接口技术在视频处理芯片中的应用   总被引:1,自引:0,他引:1  
文章使用传输I^2C总线技术实现视频处理芯片与PC机的数据通信。采用软、硬件协同工作的方法完成芯片的参数初始化,并将其应用于对电路内部节点的跟踪和测试,极大地增加了视频处理的灵活性。将I^2C接口电路内嵌于视频处理芯片中,采用CMOS0.6μm单层多晶硅双层金属布线工艺流片,电路测试功能正常。  相似文献   
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