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71.
72.
在盲源分离(BSS)算法中,对分离信号独立性的衡量直接影响算法的有效性和健壮性,是一个算法成功与否的关键因素。总结了衡量分离信号间独立性大小的一般原则,即从非高斯极大、互信息最小及非线性不相关等角度来衡量。提出了另一种衡量信号独立性的方法以及相关优化函数,拓展了BSS研究的一般思路。 相似文献
73.
一种新的小波域盲水印算法 总被引:3,自引:0,他引:3
文章提出了一种新的小波域鲁棒性水印算法,将载体图像小波变换后的近似子带进行分块,结合HVS,用密钥对子块进行选择,直接进行灰度水印的嵌入。该算法具有嵌入和提取过程十分简单、水印嵌入信息量大、鲁棒性强等突出特点,并能够实现水印盲检测。 相似文献
74.
一种有效的语音盲信号分离简化混合模型 总被引:13,自引:2,他引:13
本文针对语音盲信号分离问题,提出了一种新的简化混合模型.基于从同一声源到距离靠近(距离大约在几十厘米的范围内)的两个麦克风的房间冲激响应具有相似性这一特点,该模型只需利用这两个冲激响应的差异信息,因而简化了盲源分离的计算复杂度.自行设计实现的语音盲信号分离实时DSP实验系统证实,该模型有效可行,特别是通过引入时间延迟来解决非最小相位传递函数的求逆问题使得盲信号分离性能得到显著的改善. 相似文献
75.
Huo R Wehrens R Buydens LM 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2004,169(2):2972-269
The quality of DOSY NMR data can be improved by careful pre-processing techniques. Baseline drift, peak shift, and phase shift commonly exist in real-world DOSY NMR data. These phenomena seriously hinder the data analysis and should be removed as much as possible. In this paper, a series of preprocessing operations are proposed so that the subsequent multivariate curve resolution can yield optimal results. First, the baseline is corrected according to a method by Golotvin and Williams. Next, frequency and phase shift are removed by a new combination of reference deconvolution (FIDDLE), and a method presented by Witjes et al. that can correct several spectra simultaneously. The corrected data are analysed by the combination of multivariate curve resolution with non-linear least square regression (MCR-NLR). The MCR-NLR method turns out to be more robust and leads to better resolution of the pure components than classic MCR. 相似文献
76.
有望解决数字媒体版权纠纷的数字水印技术须满足3个相互冲突的基本要求:不可见性、健壮性和嵌入容量。应用信息论中多维无记忆加性高斯信道容量公式,提出一种基于图像内容的高容量算法。算法在保证水印不可见性的前提下,尽可能多地嵌入强度大的水印信息。水印的检测不需要原始图像,属于盲水印算法。仿真结果表明,运用该算法在图像中能嵌入较多的水印信息,同时具有很好的健壮性。 相似文献
77.
文章主要就普通垂直电镀设备下0.15mm的微盲孔电锡蚀刻保护工艺进行阐述,详细讲述了该工艺条件下的工艺参数控制。 相似文献
78.
基于高阶统计量的逆滤波器准则(IFC)和超指数迭代算法(SEA)已经被广泛地应用于解决盲均衡问题。Chi,Feng和Chen通过对两种算法的性能分析提出在特定的条件下SEA和IFC算法的得到的均衡器是等价的。基于这种等价性,文献中提出通过对这两种算法进行组合来提高算法性能的改进方案。采用这种改进的改进方案,将一种最新的改进的SEA算烈和IFC算法进行组合,提出一种收敛性又好,收敛速度又快的组合算法。 相似文献
79.
80.
In this paper, blind adaptive multiuser detection (MUD) technique is developed for uplink transmission in multiuser space
diversity DS-CDMA system to overcome multipath fading effect and multiple access interference. The system consists of a space
diversity, a precombining blind adaptive detector (PBAD), and a weight adaptation technique based on the minimization of the
mean output energy (MOE). The bit error rate (BER) performance of this receiver for asynchronous DS-CDMA signals with independent
and correlated antenna branches under Nakagami fading channel for BPSK system is evaluated. It has been seen that the use
of antenna diversity can yield substantial improvement in performance even if the correlation between the antenna elements
is relatively large (up to 0.795). However, the large correlation values pose a significant reduction in the diversity gain
in comparison with the zero correlation situation. It has also been confirmed by simulations that the PBAD provides a significant
receiver performance in comparison with the RAKE receiver employing antenna diversity.
Khodr A. Saaifan Born in lebanon 1978, received B.S.c. degree in electrical and electronics engineering (with honors) from Benha higher institute
of technology, Benha, Egypt, in 2001, and the M.S.c. degree in communications from Cairo University, Giza, Egypt, in 2005.
He is currently pursuing for the Ph.D. degree at the Cairo University. His current research interest includes space–time-coded
transmission, multiple-input multiple-output (MIMO) systems, fading channels, equalization, turbo (iterative) processing,
and wideband code division multiple access (WCDMA).
Emad K. Al-Hussaini received his B.Sc degree in Electrical Communication Engineering from Ain-Shams University, Cairo, Egypt, in 1964 and his
M.Sc and Ph.D. degrees from Cairo University, Giza, Egypt, in 1974 and 1977, respectively. From 1964 to 1970, he was with
the General Egyptian Aeroorganization. Since 1970, he has been with the Department of Electronics and Communications, Faculty
of Engineering, Cairo University, and is currently professor there. He was a research fellow at Imperial College, London,
UK, and at the Moore School of Electrical Engineering, University of Pennsylvania, Philadelphia, PA, USA, in the academic
years 1976/1977 and 1981/1982, respectively. In 1990, he received the Egyptian national encouragement award for outstanding
engineering research. He has written several papers for technical international journals and conferences. His research interests
include signal processing, fading channel communication, modulation, and cellular mobile radio systems. Dr Al-Hussaini is
a senior member of IEEE. He is listed in Marquis Who's Who in the World and in the IBC (International Biographical Center,
Cambridge) for outstanding people of the 20th century. 相似文献