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径向基函数神经网络是一种具有局部逼近能力的前向神经网络,可用作码分多址中的多用户检测器,有较好的检测性能;但是目前的RBF网络多用户检测器收敛慢,不能针对实时变化的动态信道作跟踪.针对动态信道中的多用户检测问题,借鉴免疫系统二次应答原理提出了一种基于免疫机制的RBF网络.该方法结合免疫记忆机制和免疫应答机制设计免疫算子,针对动态模型中的稳定部分和突变部分作不同强度的训练;借鉴免疫系统的二次应答机制,较大地降低了算法复杂度,并且收敛快、鲁棒性强,提高了在变化的信道中的多用户检测器的动态追踪能力. 相似文献
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多用户检测技术在DS-CDMA中的应用与发展 总被引:2,自引:0,他引:2
分析了多用户检测技术在DS-CDMA中的发展,对多用户检测的各类多用户检测技术进行简要分析比较。在简要介绍基础的多用户检测技术分类后,对现阶段多用户检测的主要研究技术方向作出了分析介绍。 相似文献
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多用户检测及其在IMT—2000中的应用 总被引:1,自引:0,他引:1
本文研究了应用于CDMA移动通信系统的各种多用户检测算法的原理和优缺点。首先指出多用户检测技术主要分为线性多用户检测和干扰对消多用户检测两类,然后对各类多用户检测技术的特点进行了分析比较。最后,探讨了用软件无线电实现多用户检测的可行性。 相似文献
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多用户检测算法及其在IMT-2000中的应用 总被引:3,自引:0,他引:3
本文研究了应用于CDMA移动通信系统的各种多用户检测算法的原理和优缺点。首先指出多用户检测技术主要分为线性多用户检测和干扰对消多用户检测两类,然后对各类多用户检测技术的特点进行了分析比较。最后,探讨了用软件无线电实现多用户检测的可行性。 相似文献
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多用户检测技术可抑制多址干扰(MAI),从而提高CDMA系统的容量和性能。多用户检测技术主要分为线性多用户检测和非线性多用户检测两种。文中对各种多用户检测的特点进行了分析比较。 相似文献
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首先分析了CDMA移动通信系统中采用多用户检测的必要性 ,然后介绍了各种多用户检测技术的工作原理 ,对各种多用户检测技术的特点进行了分析比较 ,最后提出了目前多用户检测技术的一些最新发展方向。 相似文献
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在MC-CDMA系统中检测技术是影响系统性能的关键技术之一。这里首先对最优多用户检测方法做出了简要的分析,然后引入蚁群算法多用户检测,使用最优多用户检测的判决准则作为蚁群算法中的目标函数,并对蚁群算法多用户检测和其他多用户检测性能做了仿真比较。结果表明蚁群算法多用户检测和其他次优多用户检测相比,具有较好的性能;和最优多用户检测相比具有很低的复杂度。在多用户检测的实际应用中表现出了很大的优势。 相似文献
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CDMA多用户检测技术 总被引:1,自引:0,他引:1
首先分析了CDMA移动通信系统中采用多用户检测的必要性,然后介绍了各种多用户检测技术的工作原理,对各种多用户检测技术的特点进行了比较,最后提出了目前多用户检测技术的一些最新发展方向。 相似文献
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Ai Bo Yang Zhi-Xing Pan Chang-Yong Zhang Tao-Tao Wang Yong Ge Jian-Hua 《Wireless Personal Communications》2006,38(4):495-507
In this paper, we focus on the Look-up Table (LUT) technique for the compensation of HPA nonlinear distortion. An improved LUT method is proposed with better performance compared with conventional LUT technique in terms of convergence speeds, BER and total degradation (TD). It can get over 8 dB gain in out-of-band spectrum re-growth suppression and about 0.3 dB BER performance gain than conventional LUT technique with the same iteration times. Also, we propose an actual application of HPA with pre-distorter in OFDM transmitter.
Ai Bo was born in Shannxi Province in China on February 7, 1974. He received a BSc. Degree from Engineering Institute of Armed Police Force in 1997, a Master and Dr. degree from Xidian University in 2002 and 2004 in China respectively, and now working as a post dr. in Dept. of E&E, state of key lab. on microwave and digital communications in Tsinghua University in China. He has once participated in the key research project on HDTV in TEEG (Team of Engineering Expert Group) of China. He is an editorial committee member of journal of “Computer Simulations”, “Information and Electronic Engineering”, an IEEE member and a senior member of Electronics Institute of China (CIE). He has published over 60 scientific papers in his research area till now. His current interests are the research and applications of OFDM techniques with emphasis on synchronization and HPA linearization techniques.
Yang Zhi-Xing graduated from Tsinghua University, P.R. China in 1970. He is now a Professor and Deputy Director of State Key Lab. on Microwave and Digital Communication at the Department of Electronic Engineering and the Director of the DTV R&D Center in Tsinghua University. As a DTV technical expert for the Chinese government, Professor Yang has also been a member of the DTV standardization Committee of China and a leader of the DTV Standardization Harmonizing Group in Ministry of Information Industry of China. His major research interests include broadband information transmission technologies and DTV broadcasting systems.
Pan Chang-Yong received the B.S. and M.S. degrees from the Department of Electronic Engineering in Tsinghua University, P.R. China, in 1996 and 1999, respectively. He is now an associate professor in the Department of Electronic Engineering and a member of the DTV R&D Center in Tsinghua University. His research interests are in the areas of broadband wireless transmission systems and satellite communications.
Zhang Tao-Tao was born in Shandong Province in China in 1982, he received BSc. degree from Tsinghua University in 2004 and now pursing his Master degree in Dept. of E&E, state of key lab. on microwave and digital communications in Tsinghua University in China. His research interests is the power amplifier linearization techniques.
Wang Yong was born in Shannxi Province in China in 1976. He received a BSc., a Master and a Dr. Degree from Xidian University in China in 1997, 2002 and 2005, respectively, and now is an associate professor in Xidian University. He has once participated in the key research project on HDTV in TEEG (Team of Engineering Expert Group) in China and is an IEEE Member. His interests are broadband multimedia communications.
Ge Jian-Hua was born in September, 1961 in JiangSu Province in China. He received the B.Sc., Master and Ph.D. degree from Xidian University in 1982, 1985 and 1989, respectively. He is now the professor in both Xidian University in Xi’an and Shanghai Jiaotong University in Shanghai. He is the senior member of Chinese Electronics Institute. He has won lots of scientific and technical prizes in China and published many papers. His interests are transmission communications and web security. 相似文献
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Hao‐Cheng Yang Ruben Z. Waldman Ming‐Bang Wu Jingwei Hou Lin Chen Seth B. Darling Zhi‐Kang Xu 《Advanced functional materials》2018,28(8)
Mussel‐inspired chemistry has attracted widespread interest in membrane science and technology. Demonstrating the rapid growth of this field over the past several years, substantial progress has been achieved in both mussel‐inspired chemistry and membrane surface engineering based on mussel‐inspired coatings. At this stage, it is valuable to summarize the most recent and distinctive developments, as well as to frame the challenges and opportunities remaining in this field. In this review, recent advances in rapid and controllable deposition of mussel‐inspired coatings, dopamine‐assisted codeposition technology, and photoinitiated grafting directly on mussel‐inspired coatings are presented. Some of these technologies have not yet been employed directly in membrane science. Beyond discussing advances in conventional membrane processes, emerging applications of mussel‐inspired coatings in membranes are discussed, including as a skin layer in nanofiltration, interlayer in metal‐organic framework based membranes, hydrophilic layer in Janus membranes, and protective layer in catalytic membranes. Finally, some critical unsolved challenges are raised in this field and some potential pathways are proposed to address them. 相似文献
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中国地区云量和云光学厚度的分布与变化趋势 总被引:1,自引:0,他引:1
利用最新的1983~2009年国际卫星云气候计划(ISCCP) D2月平均资料集,得到了中国地区总云量、低云量、中云量、高云量与云光学厚度的分布与变化趋势,结果表明:中国总云量和中云量呈现南多北少的分布,青藏高原地区高云量较大而低云量很小;总云量和中云量在东部呈增加趋势,西部呈减小趋势,低云量和高云量在大部分地区呈减小趋势。从不同季节来看,春季和秋季北方总云量增加,西部总云量减小;夏季大部分地区总云量增加,冬季大部分地区总云量减少。云的光学厚度呈现南多北少的分布,且在大部分地区呈增加趋势。同时利用中分辨率成像光谱仪(MODIS)资料分析了2001~2013年间中国不同污染地区总云量与云光学厚度的分布及变化趋势的异同,结果表明:中国不同污染地区云量与云光学厚度呈现不同的分布和变化规律。 相似文献
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Fahimeh Rezaei Michael Hempel Hamid Sharif 《Wireless Communications and Mobile Computing》2015,15(8):1290-1307
Advances in wireless communication protocols and networking toward support of the next generation of mobile and radio broadband technologies have contributed to a strong competition among various telecommunication standards in particular Long Term Evolution (LTE) and Mobile Worldwide Interoperability for Microwave Access (WiMAX). In this paper, we provide an in‐depth comparison analysis of LTE and Mobile WiMAX at the physical (PHY) layer by studying the most similar PHY configuration scenarios for these two technologies. Our study includes a throughput analysis of downlink (DL) and uplink (UL) transmissions in time division duplex with the least overhead possible and different antenna schemes as well as modulation and code rates. This study also performs an overhead analysis in both protocols to provide a more in‐depth understanding of the PHY layer capacity in various PHY layer configurations. Our simulation results generally show higher performance for LTE in both DL and UL transmission with 7 Mbps in DL and 5 Mbps in UL, when using one antenna port. However, by increasing the number of antennas for multiple‐input/multiple‐output configurations, the results illustrate a reduction in the performance of LTE compared to Mobile WiMAX. This arises from the increase in reference signal overhead in LTE from 4.7% in single‐input/single‐output (SISO) to 14.28% in 4 × 4 multiple‐input/multiple‐output (MIMO). Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
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Chandra Sekhar A. Durisety Rajagopal Vijayraghavan Lakshmipriya Seshan Syed K. Islam Benjamin J. Blalock 《Analog Integrated Circuits and Signal Processing》2006,48(2):143-150
This paper demonstrates a technique for controlling the electron emission of an array of field emitting vertically aligned
carbon nanofibers (VACNFs). An array of carbon nanofibers (CNF) is to be used as the source of electron beams for lithography
purposes. This tool is intended to replace the mask in the conventional photolithography process by controlling their charge
emission using the “Dose Control Circuitry” (DCC). The large variation in the charge emitted between CNFs grown in identical
conditions forced the controller design to be based on fixed dose rather than on fixed time. Compact digital control logic
has been designed for controlling the operation of DCC. This system has been implemented in a 0.5 μm CMOS process.
Chandra Sekhar A. Durisety received his B.E. (Hons.) Instrumentation from Birla Institute of Technology and Sciences, Pilani, India in 1997 and his
M.S in Electrical Engineering from University of Tennessee, Knoxville in 2002. Since 2003, he has been working towards his
Ph.D degree also in Electrical Engineering at Integrated Circuits and Systems Lab (ICASL), University of Tennessee, Knoxville.
He joined Wipro Infotech Ltd, Global R & D, Bangalore, India in 1997, where he designed FPGA based IPs for network routers.
Since 1999, he was involved in the PCI bridge implementation at CMOS chips Inc, Santa Clara, CA, and the test bench development
for Sony’s MP3 player, while at Toshiba America Electronic Components Inc., San Jose, CA. His research interests include multi-stage
amplifiers, data converters, circuits in SOI and Floating Gate Devices.
Rajagopal Vijayaraghavan received the B.E degree in electronics and communication engineering from Madras University in 1998 and the M.S degree in
electrical engineering from the University of Texas, Dallas in 2001.He is currently working towards the Ph.D degree in electrical
engineering at the University of Tennessee. His research interest is in the area of CMOS Analog and RF IC design. His current
research focuses on LNAs and VCOs using SOI based MESFET devices.
Lakshmipriya Seshan was born in Trivandrum, India on April 30, 1979. She received her B.tech in Electronincs & Communication Engg from Kerala
University, India in June 2000 and M.S in Electrical Engg from University of Tennessee in 2004. In 2004, she joined Intel
Corporation as an Analog Engineer, where she is engaged in the design of low power, high speed analog circuits for various
I/O interface topologies.
Syed K. Islam received his B.Sc. in Electrical and Electronic Engineering from Bangladesh University of Engineering and Technology (BUET)
and M.S. and Ph.D. in Electrical and Systems Engineering from the University of Connecticut. He is presently an Associate
Professor in the Department of Electrical and Computer Engineering at the University of Tennessee, Knoxville. Dr. Islam is
leading the research efforts of the Analog VLSI and Devices Laboratory at the University of Tennessee. His research interests
are design, modeling and fabrication of microelectronic/optoelectronic devices, molecular scale electronics and nanotechnology,
biomicroelectronics and monolithic sensors. Dr. Islam has numerous publications in technical journals and conference proceedings
in the areas of semiconductors devices and circuits.
Benjamin J. Blalock received his B.S. degree in electrical engineering from The University of Tennessee, Knoxville, in 1991 and the M.S. and
Ph.D. degrees, also in electrical engineering, from the Georgia Institute of Technology, Atlanta, in 1993 and 1996 respectively.
He is currently an Assistant Professor in the Department of Electrical and Computer Engineering at The University of Tennessee
where he directs the Integrated Circuits and Systems Laboratory (ICASL). His research focus there includes analog IC design
for extreme environments (both wide temperature and radiation immune), multi-gate transistors and circuits on SOI, body-driven
circuit techniques for ultra low-voltage analog, mixed-signal/mixed-voltage circuit design for systems-on-a-chip, and bio-microelectronics.
Dr. Blalock has co-authored over 60 published refereed papers. He has also worked as an analog IC design consultant for Cypress
Semiconductor Corp. and Concorde Microsystems Inc. 相似文献
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In many developing countries such as Saudi Arabia the adoption of cloud computing is still at an early stage. This research aims to investigate the influencing factors in the decision to adopt cloud computing in the private sector. An integrated model is proposed incorporating critical factors derived from a literature review, along with other factors (such as physical location) that have not been examined in previous studies as main factors in the organisation’s decision to adopt cloud services. Data were collected from 300 IT staff in different organisations in the private sector in Saudi Arabia, in order to test the cloud adoption model and explore factors that were positively or negatively associated with cloud adoption. The most influential determinants of cloud adoption were found to be quality of service and trust. However, security and privacy concerns still prevent cloud adoption in this country. This study also showed that the effect of these variables differed according to organisation size and in adopter and non-adopter companies. Overall, these research findings provide valuable guidelines to cloud providers, managers, and government policy makers on ways of encouraging the spread of cloud computing in Middle Eastern countries and increasing its implementation, particularly in Saudi Arabia. 相似文献
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针对汽车在行使过程中,穿梭于城市与城市之间,不同城市的电视频率划分不同,导致CMMB移动数字电视接收在边界点中断,设计了一种后台自动搜索电视节目信号,解析电视节目列表的方法,实现收看电视节目的无缝切换,阐述了系统框图,给出了系统软件设计,实验与应用证明该方法在多频网及单频网中都高效可行。 相似文献