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81.
In this paper, we give a convergence theorem and error estimates for an iteration method under new Kantorovitch-Ostrowski type condition using the information of higher derivatives at initial points. Compared with the corresponding study in [3],the convergence determination is established under one global condition, instead of two , on the function. 相似文献
82.
线性联合检测算法在TD-SCDMA系统中的性能分析与比较 总被引:18,自引:3,他引:15
时分、同步码分多址(TD-SCDMA)系统是基于时分双工(TDD)的块传输系统,它使用了联合检测这项关键技术来抵抗符号间干扰(ISI)和多址干扰(MAI)。以上行链路为例,本文分析了三种线性联合检测算法--匹配滤波块均衡器(MF-BLE)、迫零块均衡器(ZF-BLE)和最小均方误差块均衡器(MMSE-BLE)。从理论上,我们描述了这三种线性联合检测算法的基本原理,并对它们进行了比较(包括抗干扰性能和计算量)。随后,我们模拟了不同参数条件下(信道模型、码道数目、天线数目)这几种算法的性能,并与理论分析进行对照,得出一定结论。 相似文献
83.
崔霞 《高等学校计算数学学报(英文版)》2002,11(1):76-88
A new alternating direction (AD) finite element (FE) scheme for 3-dimensional nonlinear parabolic equation and parabolic integro-differential equation is studied. By using AD, the 3-dimensional problem is reduced to a family of single space variable problems, calculation work is simplified; by using FE, high accuracy is kept; by using various techniques for priori estimate for differential equations such as inductive hypothesis reasoning, the difficulty arising from the nonlinearity is treated. For both FE and ADFE schemes, the convergence properties are rigorously demonstrated, the optimal H1-and L2-norm space estimates and the 0((△t)2) estimate for time variable are obtained. 相似文献
84.
采用信息融合技术的IR/MMW复合导引头的目标跟踪 总被引:2,自引:0,他引:2
从误差测量环节入手,基于IR/MMW双模结构,采用信息融合处理技术提高其估计跟踪精度,最终达到降低制导误差,提高武器性能的目的,仿真结果验证了该方法的有效性。 相似文献
85.
静电驱动悬臂梁数模转换器设计、分析与模拟 总被引:1,自引:0,他引:1
提出了一种新型的微电子机械数模转换器 (MEMDAC)———静电驱动悬臂梁数模转换器 .与传统的静电驱动悬臂梁执行器相比 ,新的结构能更精确地控制梁的挠度 .文中给出了此MEMDAC的设计、分析和模拟过程 .有限元(FEA)分析表明此MEMDAC的最大输出位移为 1 5 1μm ,分辨率为 0 1μm ,其最大非线性误差为 0 0 3μm . 相似文献
86.
Inexact Newton methods for the nonlinear complementarity problem 总被引:2,自引:0,他引:2
Jong-Shi Pang 《Mathematical Programming》1986,36(1):54-71
An exact Newton method for solving a nonlinear complementarity problem consists of solving a sequence of linear complementarity
subproblems. For problems of large size, solving the subproblems exactly can be very expensive. In this paper we study inexact
Newton methods for solving the nonlinear, complementarity problem. In such an inexact method, the subproblems are solved only
up to a certain degree of accuracy. The necessary accuracies that are needed to preserve the nice features of the exact Newton
method are established and analyzed. We also discuss some extensions as well as an application.
This research was based on work supported by the National Science Foundation under grant ECS-8407240. 相似文献
87.
Multi-User MIMO Mobile CDMA Uplink System Employing Turbo Coding and Joint Detection Through a Multipath Rayleigh Fading Channel 总被引:1,自引:1,他引:0
Yasmine A. Fahmy Hebat-Allah M. Mourad Emad K. Al-Hussaini 《Wireless Personal Communications》2006,38(3):325-341
In this paper, a generalized multiple-input multiple-output (MIMO) antenna system that can be fitted to the uplink of a wireless communication system is considered for the general case of multi-user. At the transmitter, the information bits are Turbo coded, then interleaved and passed through a serial-to-parallel converter. The channel is assumed bad urban suffering from multipath Rayleigh fading resulting in inter-symbol and multiple access interferences (ISI and MAI). At the front-end of the receiver, a number of receiving antennas are used followed by a joint multi-user estimator based on the Minimum Mean Square Error Block Linear Equalizer (MMSE-BLE).Computer simulations demonstrate a significant performance improvement in both single user and multi-user cases.This paper depends in parts on that presented at the 11th European Wireless Conference, Cyprus, Nicosia, pp. 187–192, April 2005.
Yasmine A. Fahmy was born in Guiza, Egypt, on June 4, 1976. She received the B.Sc., M.Sc. and Ph.D. degrees in Communication and Electronics engineering from Cairo University, Egypt on 1999, 2001 and 2005 respectively. She is presently an assistant professor at Cairo University, Egypt. Her current field of interest is wireless communication and channel estimation.
Hebat-Allah M. Mourad received her B.Sc., M. Sc. and Ph.D. degrees in electrical communication engineering from Cairo University, Egypt, in 1983, 1987 and 1994 respectively. Since 1983, she has been with the Department of Electronics and Communications, Faculty of Engineering, Cairo University, and is currently associate professor there. Her research interests include optical fiber communications, mobile and satellite communications.
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 Whos Who in the World and in the IBC (International Biographical Center, Cambridge) for outstanding people of the 20th century. 相似文献
88.
第二类Fredholm积分方程的泰勒展开解法 总被引:3,自引:0,他引:3
本进一步发展了用Taylor公式求解第二类Fredholm积分方程的方法,并给出了近似解的误差精度分析. 相似文献
89.
Fault-based side channel cryptanalysis is very effective against symmetric and asymmetric encryption algorithms. Although straightforward hardware and time redundancy based concurrent error detection (CED) architectures can be used to thwart such attacks, they entail significant overhead (either area or performance). In this paper we investigate two systematic approaches to low-cost, low-latency CED for symmetric encryption algorithm RC6. The proposed techniques have been validated on FPGA implementations of RC6, one of the advanced encryption standard finalists. 相似文献
90.
We propose a minimum mean absolute error linear interpolator (MMAELI), based on theL
1 approach. A linear functional of the observed time series due to non-normal innovations is derived. The solution equation
for the coefficients of this linear functional is established in terms of the innovation series. It is found that information
implied in the innovation series is useful for the interpolation of missing values. The MMAELIs of the AR(1) model with innovations
following mixed normal andt distributions are studied in detail. The MMAELI also approximates the minimum mean squared error linear interpolator (MMSELI)
well in mean squared error but outperforms the MMSELI in mean absolute error. An application to a real series is presented.
Extensions to the general ARMA model and other time series models are discussed.
This research was supported by a CityU Research Grant and Natural Science Foundation of China. 相似文献