一种分类搜索的快速相关跟踪新算法

基于对交通视频序列的运动矢量时空相关性的研究,提出了一种分类搜索的快速相关跟踪新算法.该算法提出了两种不同的搜索策略:三角形搜索策略和分层三步搜索策略,在跟踪过程中依据运动类型灵活使用,减少了搜索点数,具有基于图像内容搜索的特点.实验结果表明,此算法的跟踪精度优于三步搜索法,与菱形搜索法接近.平均跟踪时间比菱形搜索法降低了23%,比三步搜索法降低了24%.     

基于三步搜索法的特征相关目标跟踪算法

针对相关匹配跟踪算法,提出一种新的基于三步搜索法的特征相关跟踪算法。该算法利用Moravec算子提取目标灰度特征,并根据特征点选取相应的子模板,然后利用三步搜索法进行多子模板的相关匹配。该方法可以在大幅度缩短相关匹配的搜索过程的基础之上适应运动目标的旋转、缩放等情况。实验证明该算法实际应用的可行性。     

精确对准过程中的算法研究

文章基于单模阵列光纤与平面光波导对准的理论模型,对在精确对准过程中常见的两种位置搜索法(爬山法和模式搜索法)进行了仿真模拟实验.仿真实验证明模式搜索法可以更快地搜索到最大光功率值,算法收敛性明显好于爬山法.     

用于快速块运动预测的多方向钻石搜索算法

传统的钻石搜索算法只考虑块误差梯度下降最大的方向,从而降低了得到最佳匹配点为全局最优的概率.在钻石搜索算法的基础上,提出了多方向钻石搜索算法,用于实现视频编码中的块运动估计.该算法考虑所有的块误差梯度下降的方向,而不是只考虑梯度下降最大的那个方向,在钻石搜索法的第一步之后,对LDSP(Large Diamond Search Pattern,LDSP)外围8个点中小于中心点BDM(Block Distortion Measure,BDM)的方向上执行搜索.与全搜索、新三步搜索、四步搜索、基于块的梯度下降搜索、钻石搜索算法相比较,实验结果表明该算法在搜索速度和搜索质量上性能较好.     

WCDMA的小区搜索及其实现算法

对WCDMA三步小区搜索各步的实现算法进行了研究，充分考虑了频差对初始小区搜索的影响，给出了各步优化的实现算法。     

阵列天线波束赋形的混合遗传算法优化

本文提出了一种应用于阵列天线波束赋形优化的混合遗传算法.该算法将简化的步长加速法作为一个局部搜索算子,融入到基于实数编码的遗传算法中.局部搜索算子的引入,使得新算法同时具有了传统遗传算法在全局搜索时的鲁棒性和步长加速法在局部搜索中搜索较快的优点.文中分别利用该算法对16元直线阵列进行了平顶波束和余割平方波束赋形优化,仿真结果表明了该算法在阵列天线波束赋形优化问题上的应用是有效的.     

用于快速块运动估计的多方向钻石搜索算法

在钻石搜索算法的基础上,提出了多方向钻石搜索算法,用于实现视频编码中的块运动估计.该算法考虑所有的块误差梯度下降的方向,而不是只考虑梯度下降最大的那个方向.与全搜索、新三步搜索、四步搜索、基于块的梯度下降搜索、钻石搜索算法相比较,实验结果表明该算法在搜索速度和质量上表现良好.     

WCDMA第一步小区搜索算法研究

本文对 WCDMA三步小区搜索第一步小区搜索实现算法进行了研究 ,充分考虑了频差对初始小区搜索的影响 ,提出了一种主同步信道匹配滤波器的实现方式。文中给出的算法减少了实现的复杂度 ,适用性好 ,对于不同情形下的小区搜索并不需要对算法本身进行修改。     

网格搜索法优化的支持向量机室内可见光定位

采用信号强度特征建立指纹库,通过网格搜索法对支持向量机参数进行优化,利用SVM回归算法建模位置坐标和信号强度特征的映射关系,实现对待定位点位置坐标的预测。在待定位点误差范围内建立子集指纹库,根据欧式距离的远近分配权值,对预测到的坐标进一步优化,实现误差最小化。将没有优化的支持向量机与用网格搜索法、蚁群算法、粒子群算法优化后进行对比,实验结果表明,使用网格搜索法优化后的SVM回归算法可以实现良好的定位效果,最终平均定位误差可达到0.042 m,且算法所需时间优于蚁群算法,寻找全局最优解优于粒子群算法。     

多参考点三步搜索法快速稳像算法

针对数字稳像（DIS）算法的实时实现，提出了基于三步搜索（TSS）法和投影算法（PA）的快速DIS算法，并在TSS法的每一步保留多个参考点以提高稳像精度使其更接近于全搜索块匹配法（FS-BM）。仿真实验表明，该算法具有较高的运动估计精度及更快的运算速度，可用于较复杂运动估计模型的实时处理。     

光通信地面网络候选站址的大气信道特性统计检验

激光通信地面站址的大气信道特性决定着设备性能的有效发挥。选择四个候选站址,西藏阿里、青海德令哈、四川稻城和河北兴隆,统计检验云量覆盖、大气透过率、天空辐射度和大气湍流等特征对激光通信的影响。结果显示,单站可用度条件以阿里为最佳；三站联合可用度以阿里-德令哈-兴隆最好,在少云条件下(云量低于60%)全年可用度85%以上;少云条件下的四站联合可用度在5~8月为91\%~96\%,其它月份98%以上。四个候选站址的大气光学特性均能满足激光通信传输的要求。高海拔站址的大气透过率与辐射度有明显优势,阿里、稻城的夜间大气相干长度在10 cm以上,德令哈在8~12 cm间, 兴隆站在6 cm以上。在多站联合模式下应能在高海拔的少云区选择出足够高可用度的站址。     

A Blind Modulation Type Detector for DPRS Standard

In this paper, some methods allowing automatic discrimination between the types of modulations proposed by the DPRS communication standard are presented. In a non-cooperative context, the receiver must first be able to detect the presence of a modulated signal before eventually carrying out its demodulation (i.e. having access to the information). For this purpose a receiver capable of identifying digital modulations of type M-QAM, 8-PSK and GMSK, proposed by the ETSI–DPRS standard, has been studied. Three detection algorithms have been investigated. The first is based on the observation of the amplitude histograms, the second on the continuous wavelet transform and the third on the maximum likelihood for the joint probability densities of phases and amplitudes. Their performance has been evaluated against signal to noise ratio. Iyad W. Dayoub was born in Messiaf, Syria, in 1969. He received the Dipl.-Ing. degrees in electronic engineering from the University of Tichreen-Syria, in 1993. He received the Dipl.-MS from the University of Nancy-France, in 1997. In 2001, he received the Dipl of Dr.-Ing. degrees in electronics from the University of Valenciennes-France. From 1993 to 1998, he was Engineer in Siemens-Damascus, Syria. From 2000 to 2002, he has been an Instructor and Researcher at the University of Valenciennes, France. Actually, he is assistant Professor at the University of Valenciennes. His current research interests include blind equalization, detection algorithms and radio over fibre networks. Anicet Okassa M’Foubat was born in Okondja, Gabon, in 1979. He received the Dipl.-BS. degrees in electronic engineering from the University of Mons, Belgium, in 2002. He received the Dipl.-MS from the University of Valenciennes-France, in 2004. Since 2004 he is a PHD student at the University of Valenciennes. His current research interests are in blind detection algorithms and multi-users detection for radio-optical networks. Romaric Mvone Evina was born in Minvoul, Gabon, in 1975. He received the Dipl.-BS. Degrees in Physics from the University of Amiens, France, in 2002. He received the Dipl.-MS from the University of Valenciennes-France, in 2003. Since 2003 he is a PhD student at the University of Valenciennes. His current research interests are in blind detection algorithms and equalizers for cellular standards. Jean-Michel Rouvaen was born in 1947. He received his M.S. degree in 1968 and his Ph.D. degree in 1971, from the University of Lille (France). He is now Professor in electronics at University of Valenciennes. Some ten years ago, he was involved in non-linear phenomena, ultrasonics and acousto-optics. His primary research interests are now in signal processing and telecommunication.     

光网络选路和波长分配研究

文章在叙述了光网络中选路和波长分配(RWA)要解决的基本问题后,对有关方面的近年研究作了综述,主要包括:虚拓扑重构、业务量疏导的RWA、多播RWA、抗毁网络的RWA.抗毁问题涉及WDM网络的抗毁选路、区分可靠性、网状网的快速恢复、多故障下的抗毁.     

Performance of a burst-frame-based CSMA/CA protocol: Analysis and enhancement

In this paper, we develop an analytical model to evaluate the delay performance of the burst-frame-based CSMA/CA protocol under unsaturated conditions, which has not been fully addressed in the literature. Our delay analysis is unique in that we consider the end-to-end packet delay, which is the duration from the epoch that a packet enters the queue at the MAC layer of the transmitter side to the epoch that the packet is successfully received at the receiver side. The analytical results give excellent agreement with the simulation results, which represents the accuracy of our analytical model. The results also provide important guideline on how to set the parameters of the burst assembly policy. Based on these results, we further develop an efficient adaptive burst assembly policy so as to optimize the throughput and delay performance of the burst-frame-based CSMA/CA protocol. Kejie Lu received the B.E. and M.E. degrees in Telecommunications Engineering from Beijing University of Posts and Telecommunications, Beijing, China, in 1994 and 1997, respectively. He received the Ph.D. degree in Electrical Engineering from the University of Texas at Dallas in 2003. In 2004 and 2005, he was a postdoctoral research associate in the Department of Electrical and Computer Engineering, University of Florida. Currently, he is an assistant professor in the Department of Electrical and Computer Engineering, University of Puerto Rico at Mayagüez. His research interests include architecture and protocols design for computer and communication networks, performance analysis, network security, and wireless communications. Jianfeng Wang received the B.E. and M.E. degrees in electrical engineering from Huazhong University of Science and Technology, China, in 1999 and 2002, respectively, and the Ph.D. degree in electrical engineering from University of Florida in 2006. From January 2006 to July 2006, he was a research intern in wireless standards and technology group, Intel Corporation. In October 2006, he joined Philips Research North America as a senior member research staff in wireless communications and networking department. He is engaged in research and standardization on wireless networks with emphasis on medium access control (MAC). Dapeng Wu received B.E. in Electrical Engineering from Huazhong University of Science and Technology, Wuhan, China, in 1990, M.E. in Electrical Engineering from Beijing University of Posts and Telecommunications, Beijing, China, in 1997, and Ph.D. in Electrical and Computer Engineering from Carnegie Mellon University, Pittsburgh, PA, in 2003. Since August 2003, he has been with Electrical and Computer Engineering Department at University of Florida, Gainesville, FL, as an Assistant Professor. His research interests are in the areas of networking, communications, multimedia, signal processing, and information and network security. He received the IEEE Circuits and Systems for Video Technology (CSVT) Transactions Best Paper Award for Year 2001, and the Best Paper Award in International Conference on Quality of Service in Heterogeneous Wired/Wireless Networks (QShine) 2006. Currently, he serves as the Editor-in-Chief of Journal of Advances in Multimedia, and an Associate Editor for IEEE Transactions on Wireless Communications, IEEE Transactions on Circuits and Systems for Video Technology, IEEE Transactions on Vehicular Technology, and International Journal of Ad Hoc and Ubiquitous Computing. He is also a guest-editor for IEEE Journal on Selected Areas in Communications (JSAC), Special Issue on Cross-layer Optimized Wireless Multimedia Communications. He served as Program Chair for IEEE/ACM First International Workshop on Broadband Wireless Services and Applications (BroadWISE 2004); and as a technical program committee member of over 30 conferences. He is Vice Chair of Mobile and wireless multimedia Interest Group (MobIG), Technical Committee on Multimedia Communications, IEEE Communications Society. He is a member of the Best Paper Award Committee, Technical Committee on Multimedia Communications, IEEE Communications Society. Yuguang Fang received a Ph.D. degree in Systems Engineering from Case Western Reserve University in January 1994 and a Ph.D. degree in Electrical Engineering from Boston University in May 1997. He was an assistant professor in the Department of Electrical and Computer Engineering at New Jersey Institute of Technology from July 1998 to May 2000. He then joined the Department of Electrical and Computer Engineering at University of Florida in May 2000 as an assistant professor and got an early promotion to an associate professor with tenure in August 2003 and to a full professor in August 2005. He has published over 200 papers in refereed professional journals and conferences. He received the National Science Foundation Faculty Early Career Award in 2001 and the Office of Naval Research Young Investigator Award in 2002. He has served on several editorial boards of technical journals including IEEE Transactions on Communications, IEEE Transactions on Wireless Communications, IEEE Transactions on Mobile Computing and ACM Wireless Networks. He have also been actively participating in professional conference organizations such as serving as The Steering Committee Co-Chair for QShine, the Technical Program Vice-Chair for IEEE INFOCOM’2005, Technical Program Symposium Co-Chair for IEEE Globecom’2004, and a member of Technical Program Committee for IEEE INFOCOM (1998, 2000, 2003–2007). He is a senior member of the IEEE.     

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.     

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.     

A Performance Comparison of Different FEC System Architectures for ATM over Wireless Multi-Carrier Modulation

In multi-carrier modulation (MCM) systems multiple relatively narrowband sub-carriers are used to alleviate the undesirable influence of frequency selective fading. This paper analyses the performance of MCM data links when forward error correction is employed either in each sub-carrier or in the main stream of bits. The influences on system performance of interleaving and suppression of the poorest sub-carriers are also analysed. José Marcos C. Brito received his diploma in electrical engineering from the National Institute of Telecommunications (Inatel), Brazil, in 1986, his M.Sc. degree in electrical engineering from State University of Campinas, Brazil, in 1998, and his Ph.D. degree in electrical engineering from State University of Campinas in 2003. Since 1986 he has been a professor at Inatel, where he has held several management positions, including vice-principal and director for research. Currently he is a Full Professor at Inatel. He has worked as a consultant for several telecommunications companies in Brazil and has published several papers in international conferences in the telecommunications area. He is the editor-in-chief of the Telecommunications Journal edited by Inatel and has served as a program committee member in some international conferences. His current research interests include computer communications networks, multiple access systems, modeling and performance evaluation of communication systems, wireless networks and error control schemes. Ivanil S. Bonatti was born in Mogi-Mirim, SP, Brazil, in 1951. He received the B.Sc. (1973) and M.Sc. (1975) degrees in Electrical Engineering from the University of Campinas, UNICAMP, Brazil, and the “Doctorat en Automatique” degree from the University Paul Sabatier, Toulouse, France, in 1981. He joined the School of Electical and computer Engineering of the University of Campinas in 1975, where he is currently a professor. His main interests are circuit theory, simulation analysis and telecommunication.     

我国周边国家和地区的CO2本底浓度及对比分析

利用世界温室气体数据中心（WDCGG）数据资料和WMO资料,对中国大陆及周边国家和地区的主要温室气体CO2浓度等进行了初步分析。分析结果表明：总体而言,中国大陆瓦里关全球大气本底站与中国香港、日本、俄罗斯、韩国等周边国家和地区CO2浓度水平相近,变化趋势一致;中国香港和韩国CO2的浓度较高,日本、俄罗斯和中国瓦里关的浓度较低。多年观测数据的研究分析显示,北半球CO2平均浓度呈现逐年升高态势,且CO2平均年变化幅度与观测站所处海拔高度成反比。中国瓦里关全球本底站与美国Mauna Loa、Barrow、Trinidad Head全球大气本底站CO2浓度水平和变化趋势较为一致,年际变化幅度略高于Mauna Loa站,低于Barrow站。中国上甸子区域大气本底站CO2浓度变化比瓦里关及美国Mauna Loa、Barrow、Trinidad Head站剧烈,显示出上甸子站受区域排放影响较强的特性。     

基于DSP的实时多任务调度内核设计

随着处理器（DSP,Digital Signal Processor）芯片在支持多任务系统中的广泛应用,传统DSP软件架构已不能满足要求。文中介绍了一个用于DSP芯片的实时多任务调度内核的实现方法。该内核是一种支持多任务、MMU和消息机制的调度内核,内核架构简洁,代码量小,占用内存少,执行效率高,完全由C语言开发,可方便地在TI公司的各种DSP上移植,可以大大加快软件开发速度,提高软件的灵活性,使DSP软件开发工作变得简单、快速。     

New layout strategies with improved matching performance

In this paper, the systematic mismatch error in integrated circuits due to gradient effects is modeled and analyzed. Three layout strategies with improved matching performance are reviewed and summarized. The hexagonal tessellation pattern can cancel quadratic gradient errors with only 3 units for each device and has high area-efficiency when extended. Both the Nth-order circular symmetry patterns and Nth-order central symmetry patterns can cancel up to Nth-order gradient effects between two devices using 2^N unit cells for each one. Among these three techniques, the central symmetry patterns have the best-reported matching performance for Manhattan structures; the circular-symmetry patterns have the best theoretical matching performance; and the hexagonal tessellation pattern has high density and high structural stability. The Nth-order central symmetry technique is compatible to all IC fabrication processes requiring no special design rules. Simulation results of these proposed techniques show better matching characteristics than other existing layout techniques under nonlinear gradient effects. Specifically, two pairs of P-poly resistors using 2nd and 3rd-order central symmetry patterns were fabricated and tested. Less than 0.04% mismatch and less than 0.002% mismatch were achieved for the 2nd and the 3rd-order structures, respectively. Chengming He was born in YiWu, China in 1976. He received his B.S. in 1999 in Electronic Engineering department and his M.S. degree in the institute of Microelectronics in 2001 at Tsinghua University, Beijing. He started to work toward his PhD in Iowa State University since August 2001. Since June 2004 he started to work as a design engineer in Silicon Laboratories, Inc., Austin, TX. He studied and designed LNA, band-pass filter and on-chip power management blocks as well as matching-enhanced layout patterns. He is interested in designing high gain low voltage amplifier, high speed power-efficient ADC and high speed high linear DAC as well as other mixed-signal circuits. He is also interested in the application of nonlinear system dynamical theory in mixed-signal design and yield-enhancement by improving layout matching. He has published more than 10 technical papers. He was a student member of IEEE from 01--04 and now is a member. He is a member of Tau Beta Pi. Xin Dai was born in Shanghai, China on March 11, 1981. She received the B.Eng. in 2003 from Shanghai Jiao Tong University, Shanghai, China. She is currently a graduate student in Department of Electrical and Computer Engineering at Iowa State University, Ames, IA. Her research has been connected to data converter design and calibrations, layout techniques and build-in-self-test. Xin Dai is now taking a summer-intern in Broadcom Corp., CA. Hanqing Xing was born in Dalian, China, in 1978. He received the B.S. and M.S. degrees with honors in Electronic Engineering from Tsinghua University, Beijing, China, in 2000 and 2003, respectively. He is currently a PhD student at Iowa State University working in analog and mixed signal design group. His research interests include analog, mixed-signal, and data-conversion integrated circuits design and test. Degang Chen received his B.S. degree in 1984 in Instrumentation and Automation from Tsinghua University, Beijing, China and his M.S. and Ph.D. degrees in 1988 and 1992, respectively, both in Electrical and Computer Engineering, from the University of California, Santa Barbara. From 1984 to 1986, he was with the Beijing Institute of Control Engineering, a space industry R/D institute. From March 1992 to August 1992, he was the John R. Pierce Instructor of Electrical Engineering at California Institute of Technology. After that, he joined Iowa State University where he is currently an Associate Professor. He was with the Boeing Company in summer of 1999 and was with Dallas Semiconductor-Maxim in summer of 2001. His research experience include particulate contamination in microelectronic processing systems, vacuum robotics in microelectronics, adaptive and nonlinear control of electromechanical systems, and dynamics and control of atomic force microscopes. His current teaching and research interests are in the area of analog and mixed-signal VLSI integrated circuit design and testing. In particular, he is interested in low-cost high-accuracy testing and built-in-self-test of analog and mixed-signal and RF circuits, and in self-calibration and adaptive reconfiguration/repair strategies for performance and yield enhancement. Dr. Chen is the recipient of the Best Paper Award at the 1990 IEEE Conference on Decision and Control and the Best Transaction Paper Award from the ASME Journal of Dynamic Systems, Measurement, and Control in 1995. He was selected an A.D. Welliver Faculty Fellow with the Boeing Company in 1999.