滚俯仰式红外导引头稳定平台控制与仿真

滚俯仰式红外导引头具有体积小、质量轻、视场大的特点,适应于现代红外导引头发展的需要.论述了滚俯仰式红外导引头的控制原理和伺服系统的组成,针对滚转、俯仰框架进行了系统建模,对稳定、跟踪、锁定回路进行了仿真,同时对滚转、俯仰框架进行了隔离度仿真测试,结果表明,设计良好的滚俯仰式红外导引头具有较低的稳态误差和较好的动态性能,及良好的抗干扰性能,满足系统要求.     

干扰条件下反舰导弹导引头伺服系统研究

反舰导弹导引头伺服系统对于目标搜索、目标跟踪和目标参数测量起着重要作用,它的精度直接影响反舰导弹制导精度.首先根据导引头伺服系统结构,在干扰条件下对导引头角稳定回路、角跟踪回路和角预定回路进行分析,建立导引头伺服系统数学模型;为提高导引头抗干扰能力,在角跟踪回路中引入Kalman滤波器,通过滤波可以为系统提供精确的目标数据;然后结合工程实际,构建导引头伺服系统的Simulink控制模型,并进行动态仿真;最后得到系统的动态响应结果.仿真结果表明,该方法可以有效提高导引头的响应速度和跟踪精度,为反舰导弹雷达导引头的工程设计提供了科学依据.     

红外成像导引头闭环注入式仿真试验系统设计及一致性分析

闭环注入式仿真是开展红外成像制导武器对抗及其复杂环境适应性试验的一种有效手段,它在传感器被图像仿真计算机和图像注入接口设备取代的情况下,采集导引头的框架角数据,实时仿真生成红外数字图像,并通过注入接口设备直接注入到导引头信息处理电路中进行试验。分析了闭环注入式仿真试验的工作原理,设计了仿真试验系统的软硬件平台、工作时序,理论计算了仿真试验系统产生的失调角延时和失调角误差,并利用搭建的仿真试验与导引头实际工作一致性分析平台,分析了因失调角延时和失调角误差导致导引头输出的偏航、俯仰角速度误差和制导精度误差。仿真结果表明:仿真试验与导引头实际工作条件是一致性的,设计的仿真试验系统较为科学合理,该结论可为开展红外成像导引头闭环注入式仿真试验提供理论支撑。     

滚仰式红外导引头视线角速率提取方法研究

由于滚仰式导引头的结构特殊性,制导控制系统需要的视线角速率信息是不能够直接测量得到的,因此提出了一种基于跟踪微分器的视线角速率提取方法。根据滚仰式导引头的结构特点,分析了滚仰式导引头的运动学原理,并根据滚仰式导引头的结构推导出视线角与弹体姿态角、框架角和失调角的关系,然后设计了有限时间收敛跟踪微分器求解视线角速率信息。经数字仿真,对比了直接差分法和跟踪微分器法对视线角速率的提取效果,证明了利用跟踪微分器提取视线角速率的有效性。     

捷联式光学导引头特性与多维度最优制导律

为实现捷联式光学成像导引头与制导系统一体化设计,建立了全捷联制导与控制系统,根据捷联导引头特性进行制导与控制原理研究。首先,建立了全捷联导引头与陀螺的数学模型;接着,针对捷联导引头无法精确提取视线角速率的问题,提出姿态驾驶仪与视线角积分比例导引相结合的控制与制导方案,并分析了导引头体视线角、刻度因数、导航比和系统稳定区域之间的关系;然后,推导了全捷联制导系统最优制导律以提高制导系统响应速度;最后,进行了控制与制导系统飞行仿真,仿真结果表明:捷联式制导与控制系统能对静止与运动目标（速度为60 km/h）进行有效攻击,最大射击误差分别为1.49 m与2.62 m;系统误差、陀螺零偏与零偏稳定性对制导系统精度影响较大。捷联导引头制导与控制系统能满足空对地系统对静止与低速运动目标的攻击要求。     

高精度高可靠性脱机追日系统研制

为实现高精度高可靠性的追踪太阳,提高对太阳能的利用率,设计了一套基于以C8051Fa020的控制系统;该系统以C8051Fa020为控制器,通过太阳能公式计算出太阳的水平角及高度角,由程序控制水平及高度电机的转动,实现对太阳位置的精确跟踪;同时利用安装在太阳能发电架构上的编码器作为反馈,实现追日系统的闭环控制,对追日系统的误差进行校正,改进跟踪系统的精度;通过对实地太阳能架构的实验,追日系统可以精确追踪太阳位置,系统性能稳定,成本低,实用性很强。     

基于指数积公式的导引头运动学分析与标定

针对半捷联俯仰偏航双框架导引头的结构特点,分析了框架的运动学描述方法.利用角速度递归算式,将弹体的惯性空间速度映射到视轴坐标系,推导出视轴的惯性空间稳定方程.基于指数积公式,给出了框架的运动学标定模型,研究了运动学方程的标定方法.将误差参数归结于框架坐标系的初始姿态,简化了运动学参数的标定过程.采用迭代最小二乘算法求解...     

基于随机森林的复合导引头跟踪模式决策

为了提高多模复合导引头跟踪模式复杂逻辑决策的适应性,采用随机森林构建模式决策网络、结合误差补偿的方法,对传统的人工条件判读流程进行了优化,提高了模型的分类准确率,并将该方法应用到复合导引头中进行理论分析和仿真验证。结果表明,得到的跟踪模式的分类正确率达100%,运行速度提升16%,代码量减少3倍; 基于随机森林和误差补偿的跟踪模式决策方法对导引头跟踪模式决策具有较好的适应性,可以高效实现跟踪模式的自主决策。此研究算法为高效率地实现导引头跟踪模式决策提供了参考。     

动力陀螺式激光导引头的动力学建模与仿真

在动力陀螺式激光导引头中,驱动装置和动力陀螺相联系的动力学特性对导引头光轴能否达到预期的运动影响很大。基于该型导引头位标器结构配置和工作原理,采用光电稳定机构运动学理论及空间坐标变换的方法,建立了以位标器光轴方位、俯仰框架角与角速度为状态变量的动力学模型,经仿真计算得到了不同弹体扰动和电磁控制输入下导引头光轴的角速度变化和耦合力矩变化曲线,分析结果符合导引头光轴的实际运动规律,为导引头陀螺伺服系统的设计与导引头半实物仿真试验结果的分析提供了模型支持。     

一种红外导引头小型快速伺服稳定平台

红外导引头是肩扛式反坦克导弹的重要分系统,其主要作用是通过瞄准具人工操作瞄准线运动,锁定目标并对目标进行跟踪。本文采用了速率陀螺稳定平台式随动系统,俯仰+偏航的双框架式结构。通过装在框架内的速率陀螺和角位置传感器分别提供速度和位置信号,利用DSP和FPGA构建随动控制电路,采用电流、速度和位置三环串级闭环PID设计控制框架电机实现目标扫描和跟踪。此方案快速跟踪能力强、跟踪精度高、抗干扰性强、易实现大范围扫描。     

Alternative Schemes for Dynamic Secure VPN Deployment in UMTS

Three alternative schemes for secure Virtual Private Network (VPN) deployment over the Universal Mobile Telecommunication System (UMTS) are proposed and analyzed. The proposed schemes enable a mobile node to voluntarily establish an IPsec-based secure channel to a private network. The alternative schemes differ in the location where the IPsec functionality is placed within the UMTS network architecture (mobile node, access network, and UMTS network border), depending on the employed security model, and whether data in transit are ever in clear-text, or available to be tapped by outsiders. The provided levels of privacy in the deployed VPN schemes, as well as the employed authentication models are examined. An analysis in terms of cost, complexity, and performance overhead that each method imposes to the underlying network architecture, as well as to the mobile devices is presented. The level of system reliability and scalability in granting security services is presented. The VPN management, usability, and trusted relations, as well as their behavior when a mobile user moves are analyzed. The use of special applications that require access to encapsulated data traffic is explored. Finally, an overall comparison of the proposed schemes from the security and operation point of view summarizes their relative performance. Christos Xenakis received his B.Sc. degree in computer science in 1993 and his M.Sc. degree in telecommunication and computer networks in 1996, both from the Department of Informatics and Telecommunications, University of Athens, Greece. In 2004 he received his Ph.D. from the University of Athens (Department of Informatics and Telecommunications). From 1998–2000 was with the Greek telecoms system development firm Teletel S.A., where was involved in the design and development of advanced telecommunications subsystems for ISDN, ATM, GSM, and GPRS. Since 1996 he has been a member of the Communication Networks Laboratory of the University of Athens. He has participated in numerous projects realized in the context of EU Programs (ACTS, ESPRIT, IST). His research interests are in the field of mobile/wireless networks, security and distributed network management. He is the author of over 15 papers in the above areas. Lazaros Merakos received the Diploma in electrical and mechanical engineering from the National Technical University of Athens, Greece, in 1978, and the M.S. and Ph.D. degrees in electrical engineering from the State University of New York, Buffalo, in 1981 and 1984, respectively. From 1983 to 1986, he was on the faculty of Electrical Engineering and Computer Science at the University of Connecticut, Storrs. From 1986 to 1994 he was on the faculty of the Electrical and Computer Engineering Department at Northeastern University, Boston, MA. During the period 1993–1994 he served as Director of the Communications and Digital Processing Research Center at Northeastern University. During the summers of 1990 and 1991, he was a Visiting Scientist at the IBM T. J. Watson Research Center, Yorktown Heights, NY. In 1994, he joined the faculty of the University of Athens, Athens, Greece, where he is presently a Professor in the Department of Informatics and Telecommunications, and Director of the Communication Networks Laboratory (UoA-CNL) and the Networks Operations and Management Center. His research interests are in the design and performance analysis of broadband networks, and wireless/mobile communication systems and services. He has authored more than 150 papers in the above areas. Since 1995, he is leading the research activities of UoA-CNL in the area of mobile communications, in the framework of the Advanced Communication Technologies & Services (ACTS) and Information Society Technologies (IST) programmes funded by the European Union (projects RAINBOW, Magic WAND, WINE, MOBIVAS, POLOS, ANWIRE). He is chairman of the board of the Greek Universities Network, the Greek Schools Network, and member of the board of the Greek Research Network. In 1994, he received the Guanella Award for the Best Paper presented at the International Zurich Seminar on Mobile Communications.     

Data Integration for Medical Information Management

We present a new method for data integration and security by mixing medical waveforms and images with encrypted patient identifiers and unencrypted ancillary information, such as acquisition parameters, diagnostic comments and notes in textual, pictorial, and voice forms. We vary the sampling rate according to the instantaneous frequency of the signal. Redundant samples (or pixels) are eliminated and replaced by associative data which are labeled using a status string encoded based on the Huffman and run-length techniques. This method achieves both data compression and integration simultaneously, allows synchronized presentation of information from different sources by using multimedia technology, and provides data security features. Mingui Sun received a B.S. degree from the Shenyang Chemical Engineering Institute, China, in 1982, and M.S. and Ph. D. degrees in Electrical Engineering from the University of Pittsburgh in 1986 and 1989, respectively. He was a Graduate Student Researcher from 1985 to 1989 working on signal and image processing projects. Currently, he is a Associate Professor and an Associate Director of the Center for Clinical Neurophysiology in the Department of Neurosurgery at the University of Pittsburgh, and a Director of Research at Computational Diagnostics, Inc. His current research and development interests include advanced biomedical electronic devices, biomedical signal and image processing, sensors and transducers, biomedical instruments, artificial neural networks, wavelet transforms, time-frequency analysis, and the inverse problem of neurophysiological signals. He has over 160 publications in these areas. Qiang Liu received his B.S. and M.S. degrees in electrical engineering from Xidian University, Xian, China, in 1996 and 1999 respectively. He is currently a Ph.D. student at the University of Pittsburgh, Pittsburgh, USA. His further research interests include biomedical signal processing, medical imaging, and image/video segmentation, coding and transmission. Robert J. Sclabassi received the B.S.E. degree from Loyola University, Los Angeles, the M.S.E.E., Engineer in Electrical Engineering, and Ph.D. degrees in electrical engineering from the University of Southern California, and the M.D. degree from the University of Pittsburgh. He was employed in the Advanced Systems Laboratory at TRW, Los Angeles, and was a postdoctoral fellow at the Brain Research Institute at the University of California, Los Angeles. He was on the faculties of Department of Neurology and Biomathematics at UCLA until he joined the University of Pittsburgh. Dr. Sclabassi is currently a Professor of Neurological Surgery, Psychiatry, Electrical Engineering, Mechanical Engineering, Psychiatry, and Behavioral Neuroscience at the University of Pittsburgh. Dr. Sclabassi has published over 400 papers, chapters and conference proceedings. Dr. Sclabassi is a Registered Professional Engineer.     

高速光纤综合通信网络平台研究

现代通信网络应能满足各种通信业务和通信容量日益发展的需求,实现话音、数据、视频、IP等业务的一体化综合交换和传输。在比较TDM、IP和ATM三种协议的基础上,提出"采用内置RPR和MPLS功能的MSTP平台"建设光纤综合通信网络平台的实现方法。MSTP采用SDH的数据帧结构,保持了SDH标准光接口、灵活分插低速信号、自愈环保护和功能强大的网管等优点,可对TDM、IP和ATM协议进行优化传输。     

Hydrogel Adhesion: A Supramolecular Synergy of Chemistry,Topology, and Mechanics

Adhering hydrogels to various materials is fundamental to a large array of established and emerging applications. The last few years have seen transformative advances in achieving strong hydrogel adhesion, which is a supramolecular phenomenon. Two adherends connect through covalent bonds, noncovalent complexes, polymer chains, polymer networks, or nanoparticles. Separating the adherends dissipates energy through cascading events across length scales, including bond cleavage, chain retraction, and bulk hysteresis. A unifying principle has emerged: strong hydrogel adhesion requires the synergy of chemistry of bonds, topology of connection, and mechanics of dissipation. This synergy characterizes hydrogel adhesion to various materials (another hydrogel, tissue, elastomer, plastic, metal, glass, and ceramic) in various operations (cast, coat, print, attach, pierce, and glue). Strong adhesion can be made permanent, reversible, degradable, or on‐demand detachable. The development of hydrogel adhesion and its applications adheres disciplines, discovers interlinks, and forges cohesion. Discussed throughout the review are immediate opportunities for fundamental studies and practical applications.     

微电子封装的新进展领域及对SMT的新挑战

介绍了几种微电子新型封装材料,如LTCC、AIN、金刚石、AI-Sic和无铅焊接材料等,论述了正在发展中的新型先进封装技术,如WLP、3D和SIP等,并对封装新领域MEMS和MOEMS作了简介.最后,就这些新技术对SMT的新挑战作了些探讨.     

A Fault-Tolerant Scheme for Mobility Management in PCS Networks

One of the most important and challenging issues in the design of personal communication service (PCS) systems is the management of location information. In this paper, we propose a new fault-tolerant location management scheme, which is based on the cellular quorum system. Due to quorum's salient set property, our scheme can tolerate the failures of one or more location server(s) without adding or changing the hardware of the systems in the two-tier networks. Meanwhile, with a region-based approach, our scheme stores/retrieves the MH location information in the location servers of a quorum set of the local region as much as possible to avoid long delays caused by the possible long-distance of VLR and HLR. Thus, it yields better connection establishment and update delay. Ming-Jeng Yang received the M.S. degree in computer science from the Syracuse University, New York, in 1991, and the Ph.D. degree in computer science from National Taiwan Normal University, Taiwan, in 2004. He is an associate professor in the Department of Information Technology, Takming College, Taiwan. His research interests include wireless networks, mobile computing, fault-tolerant computing, and distributed computing. He is a member of the IEEE Computer Society and the ACM. Yao-Ming Yeh received the B.S. degree in computer engineering from National Chiao-Tung University, Taiwan, in 1981, and the M.S. degree in computer science and information engineering from National Taiwan University, Taiwan, in 1983. In August 1991, he received the Ph.D. degree in the Department of Electrical and Computer Engineering, The Pennsylvania State University, Pa., U.S.A. He is a professor in the Department of Information and Computer Education, National Taiwan Normal University, Taiwan. His research interests include fault-tolerant computing, web and XML computing, and distributed computing.     

Metadata Design for Reconfigurable Protocol Stacks in Systems Beyond 3G

Global consensus on the next generation of wireless mobile communications, broadly termed “beyond 3G”, sketches a heterogeneous infrastructure comprising different wireless systems in a complementary manner and vested with reconfiguration capabilities, which support a flexible and dynamic adaptation of the wireless network and its spectrum resources to meet the ever-changing service requirements. For ubiquitous reconfiguration to become a practical capability of mobile communication systems, it is necessary to establish a global architecture for modeling, expressing, and circulating essential metadata related to reconfiguration, including reconfigurable device capabilities and semantic properties of protocol stacks. We outline the relevant standardization initiatives in the mobile domain, summarize existing work in reconfiguration-supporting architectures, and identify key shortcomings that may hinder the advent of ubiquitously reconfigurable systems. Further on, we point out some major limitations of current metadata standards in the mobile domain for the representation of capability information pertaining to reconfigurable protocol stacks. Next, we identify essential metadata classes in support of reconfigurable communication systems, introducing an associated object-oriented UML model. We elaborate on the design rationale of the UML model, presenting and discussing the alternative metadata representation standards and suitable encoding formats. Finally, we demonstrate the suitability of our UML model by applying our reconfiguration-supporting vocabulary in the cases of a standardized protocol stack of 3G mobile devices and stationary 3G cellular network elements. Vangelis Gazis received his B.Sc. and M.Sc. (Communication Networking) degrees from the Department of Informatics & Telecommunications of the University of Athens, Greece, in 1995, and 1998, respectively. He also received an M.B.A. degree from the Athens University of Economics and Business in 2001. Since 1996 until, he has been with the research staff of the Communication Networks Laboratory (CNL) of the University of Athens. He has participated in national and European research projects (MOBIVAS, ANWIRE) of the IST framework programme. He specializes in reconfigurable mobile systems and networks for beyond 3G, metadata and ontology languages, reflective and component middleware, adaptable services and open API frameworks for telecommunications. He is currently a Ph.D. candidate in the Department of Informatics & Telecommunications of the University of Athens. Nancy Alonistioti holds a B.Sc. degree and a Ph.D. degree in informatics and telecommunications from the University of Athens. Presently, she is a senior researcher in the Department of Informatics and Telecommunications of the University of Athens. In the past, she has held a research position with the Institute of Informatics and Telecommunications of NCSR “Demokritos” in the areas of protocol and service design and testing, mobile systems (UMTS), open architectures, and software defined radio systems and networks. Her current research interests are in reconfigurable mobile systems and networks beyond 3G, and adaptable services, pervasive computing and context awareness. She has participated in several national and European R&D projects, and has been the technical manager of the IST-MOBIVAS and IST-ANWIRE projects, which have had a focus on reconfigurable mobile systems, networks an respective service provision. She is currently a member of the management team and workpackage leader in the FP6 IST-E2R project on reconfigurability; she also serves as technical manager for the University of Athens in the FP6 IST-LIAISON project, which focuses on location based services in working environments. Dr Alonistioti is co-editor and co-author of the book entitled “Software defined radio, Architectures, Systems and Functions”, published by John Wiley in May 2003. She has authored over 55 publications in the area of mobile communications and reconfigurable systems and networks. Lazaros Merakos received the Diploma in electrical and mechanical engineering from the National Technical University of Athens, Athens, Greece, in 1978, and the M.S. and Ph.D. degrees in electrical engineering from the State University of New York, Buffalo, in 1981 and 1984, respectively. From 1983 to 1986, he was on the faculty of the Electrical Engineering and Computer Science Department, University of Connecticut, Storrs. From 1986 to 1994, he was on the faculty of the Electrical and Computer Engineering Department, Northeastern University, Boston, MA. During the period 1993D1994, he served as Director of the Communications and Digital Processing Research Center, Northeastern University. During the summers of 1990 and 1991, he was a Visiting Scientist at the IBM T. J. Watson Research Center, Yorktown Heights, NY. In 1994, he joined the faculty of the University of Athens, Athens, Greece, where he is presently a Professor in the Department of Informatics and Telecommunications, and Director of the Communication Networks Laboratory (UoA-CNL) and the Networks Operations and Management Center. Since 1995, he is leading the research activities of UoA-CNL in the area of mobile communications, in the framework of the Advanced Communication Technologies and Services (ACTS) and Information Society Technologies (IST) programs funded by the European Union (projects RAINBOW, Magic WAND, WINE, MOBIVAS, POLOS, ANWIRE, E2R, LIAISON). His research interests are in the design and performance analysis of communication networks, and wireless/mobile communication systems and services. He has authored more than 190 papers in the above areas. Dr. Merakos is Chairman of the Board of the Greek Universities Network, the Greek Schools Network, and Member of the Board of the Greek Research Network. In 1994, he received the Guanella Award for the Best Paper presented at the International Zurich Seminar on Mobile Communications.     

一个具有附益性及保序性算子的形态学非局部拓展

近年，形态学非局部拓展工作在图像处理领域受到众多关注.而附益性算子是经典形态学的最基本形式，也是形态学分析方法最重要的变换工具.为此，一些研究者就形态学非局部拓展中如何保持算子的附益性开展工作.本文从理论及实例两个方面说明，相关拓展工作为保持算子的附益性而丢失了保序性的不足；进一步，通过设计非局部权值的获取过程，并结合现有工作，本文提出了一个新的形态学非局部拓展，并定理证明了所得算子同时具备附益性及保序性两个重要性质；人工合成图像及自然图像上的仿真实验也表明了本文所提算法的有效性.     

LTE和LTE-Advanced关键技术综述

为满足移动宽带业务的需要,LTE正日渐成熟,它采用扁平化网络架构,关键技术包括OFDM、更高阶调制、HARQ、先进的多天线技术、快速同步技术、灵活的控制信道设计、自适应资源分配、干扰抑制技术等。有关LTE-Advanced的讨论也以展开,考虑的技术包括聚合多载波、高阶MIMO、智能中继、异构网络、协调多点发送和先进的干扰管理。     

Design of an ADC for subsampling video applications

This paper describes a 10 bit 30 Msample/s (MSPS) CMOS analog-to-digital converter (ADC) for high-speed signal processing, especially for subsampling applications, for example digital video broadcasting over cable (DVB-C), terrestrial (DVB-T) and handheld (DVB-H) systems. The proposed pipelined ADC shows a good figure-of-merit (FoM). It adopts a power efficient amplifier sharing technique, a symmetrical gate-bootstrapping technique with modified timing for the bottom-sampling switch of a wideband sample-and-hold (S/H) circuit, a proposed stable high-swing bias circuit for a wide-swing gain-boosting telescopic amplifier. The measured differential and integral nonlinearities of the prototype in a 0.25-μm CMOS technology show less than 0.4 least significant bit (LSB) and 0.85 LSB respectively at full sampling rate. The ADC exhibits higher than 9 effective number of bits (ENOB) for input frequencies up to about 60 MHz, which is the fourfold Nyquist rate (fs/2), at 30 MSPS. The ADC consumes 60 mW from a 3-V supply and occupies about 1.36 mm². Jian Li received the Bachelor of Engineering (B.E.) degree in electronic engineering from Xi’an Jiaotong University, Xi’an, China, in 2003. He is currently working toward the Ph.D. degree at Microelectronics department, Fudan University, Shanghai, China. His current research interest is high-speed high resolution A/D converter design. Xiaoyang Zeng was born in Hunan Province, P.R. China on April 17, 1972. He received the B.S. degree from Xiangtan University, China in 1992, and the Ph.D. degree from Changchun Institute of Optics and Fine Mechanics, Chinese Academy of Sciences in 2001. From 2001 to 2003, he worked as a post-doctor researcher at the State-Key Lab of ASIC & System, Fudan University, P.R. China. Then he joined the faculty of Department of Micro-electronics at Fudan University as an associate professor. His research interests include information security chip design, VLSI signal processing, and communication systems. Prof. Zeng is the Chair of Design-Contest of ASP-DAC 2004 and 2005, also the TPC member of several international conferences such as ASCON 2005 and A-SSCC 2006, etc. Jianyun Zhang received the B.S., M.S. and Ph.D degree in electrical engineering from Fudan University, Shanghai, China in 1997, 2000 and 2006 respectively. From 2000 to 2002, he was with Alcatel microelectronics, Belgium, where he was involved in circuit design for GSM and GPRS. In 2002, he joined Trident microsystem, where he concentrated on the design of Video AFE including data converters and mixed signal circuits. In 2005, he joined Shihong microelectronics Corp., where he is now a director of mixed signal IC for video high speed interface. His research interests include data conversion, HDMI SerDes, and analog circuit design. Lei Xie received the Bachelor of Science (B.S.) degree in microelectronics from Nankai University, Tianjin, China, in 2005. He is currently working toward the M.S. degree at Fudan University, Shanghai, China. His current research interest is high-speed high resolution A/D converter. Huan Deng received the B.S. degree in microelectronics from Fudan University, Shanghai, P.R. China, in 2003. He is currently working toward the M.S. degree in microelectronics at the State Key Lab of ASIC & System, Fudan University. He is currently involved in the design of low-power, high-speed PLL’s. Yawei Guo received the B.S. and M.S. degree in electrical engineering from Fudan University in 1999 and 2002 respectively. From 2002 to August 2003, he was with Philips Semiconductors in Shanghai. Since August 2003, he has been with Shanghai MicroScience Integrated Circuits Co., Ltd., based in Shanghai, P. R. China. He has been leading a group and developing analog and mixed signal circuits. His research interests include high-speed data communication, data converters, and phase locked loops.