基于RocketIO的SAR 雷达系统高速串行传输的实现

高速数据传输一直是合成孔径雷达系统设计的一个重点和难点。针对Xilinx 的Virtex2ⅡPRO 系列FPGA 内嵌的Rocket IO 收发器模块, 设计了一块应用于SAR 雷达通信系统中的高速串行I/O 电路板。该板充分利用了芯片中集成的Rocket IO 收发器模块, 采用BREFCLK 差分输入参考时钟, 8B/10B 编码, 预加重处理技术等, 实现了多个通道的高速互连。通过实际系统验证了这种传输的可靠性。实验结果表明: 采用Rocket IO 模块进行高速串行传输设计, 可极大简化片上逻辑电路和片外PCB 板图的设计。     

基于ESAM安全模块的电动汽车电池管理系统

当前国家正在大力推行的智能电网建设,围绕智能电网中正在推行使用的E SAM(Enbedded Secure Access Module)安全模块,与利用R F收发器进行无线传输的手持终端相结合,提出了基于ESAM安全模块的电动汽车电池管理系统。该系统在设备端使用E SAM安全模块与有源射频模块相结合,形成安全性更高的R F收发器;同时,在手持终端侧配套使用与E SAM模块相结合的安全认证体系及读头,保持了系统设备的安全性及便捷性。     

一种基于FPGA的高速传输链路的实现

为了满足某系统对于高速数据传输的需求,提出了一种基于新型内置高速通道收发器的现场可编程门阵列（FPGA）设计光纤传输适配卡的方法。论述了设备的总体设计方法和关键技术的实现,说明了设备测试方法并对结果进行了分析。由于采用FPGA,增强了进行数据传输时的灵活性,基于该方法设计的光纤传输设备还有适应性强、集成度好等特点,具有较好的应用前景。     

基于有限状态机的高速串口通信收发器的FPGA设计

针对在多任务操作系统环境下串口通信实时性和高速性受到影响的问题,提出一种基于有限状态机的高速串口通信收发器的FPGA实现方法。串口通信收发器由波特率发生器、发送模块、接收模块和控制与状态四个模块构成,波特率发生器使用锁相环对输入时钟进行倍频和分频;接收模块和发送模块分别使用一个四状态和两状态的有限状态机实现。仿真和实测结果表明,设计的FPGA串口收发器模块电路工作稳定,速度可以达到3 Mbit/s。由于FPGA的高度并行性和有限状态机的稳定性,使用有限状态机实现的FPGA高速串口通信收发器在工业应用中能保证高速串行通信的实时性和可靠性。     

基于RocketIO的SATA物理层高速串行传输实现

高速数据传输是硬盘存储系统设计的一个重点和难点,针对Virtex-4系列FPGA内嵌的RocketIO收发器模块,设计应用于SATA物理层的高速串行数据传输电路。对SATA物理层功能要求进行分析,描述RocketIO收发器的内部结构特点和工作原理,详细讨论基于RocketIO收发器的SATA物理层电路逻辑设计,重点介绍RocketIO收发器的时钟控制和复位的配置。实验结果表明:采用RocketIO收发器进行高速串行传输设计,符合SATA物理层设计要求,并提高系统的集成度和可靠性,为SATA接口的固态硬盘开发奠定基础。     

光电电流互感器高压侧编码模块的设计

介绍了光电电流互感器及其高压侧数字输出编码模块的基本原理,着重阐述了CRC编码模块的设计过程,从理论上分析了CRC校验码,并给出了实现CRC校验码的VHDL程序,在现场可编程门阵列(FPGA)上得到实现,继而将组帧数据进行曼彻斯特码编码,然后通过光纤传输至低压侧.本方案能够满足光电电流互感器对数据通讯的快速性、可靠性要求,对于电力通信系统具有广泛的应用前景.     

Xilinx隆重推出Virtex-5 FXT FPGA为高性能处理和高速串行I/O设计提供终极系统集成平台

<正>65nm Virtex-5系列FPGA第四款平台集成了PowerPC440处理器模块、GTX高速收发器,以及超过190GMACs的DSP性能全球可编程逻辑解决方案领导厂商赛灵思公司(Xilinx,Inc.(NASDAQ:XLNX))近日宣布推出Virtex-5FXT器件。这些FPGA器件在业界率先集成了嵌入式PowerPC440处理器模块、高速RocketIOTMGTX收发器和专用XtremeDSPTM处理能力。作为65nmVirtex-5系列的第四款平台,Virtex-5FXT提供了极高的性能,还可帮助设计人65nmVirtex-5系列FPGA第四款平台集成了PowerPC440处理器模块、GTX高速收发器,以及超过190GMACs的DSP性能     

8031单片机的远程数据通讯

8031单片机远程数据通讯系统,采用MRDS单路远程数据通讯控制器作传输设备,传输方式为基本带传输,传输最大距离为20km。     

基于ARM和FPGA的1553B总线设备检测系统的设计

1553B总线在军事领域应用非常广泛,目前针对1553B总线设备的检测系统并不能完全满足实际应用需求。为使计算机与1553B总线设备的数据通信更加方便,提高总线设备检测效率,基于ARM和FPGA设计了一种1553B总线设备检测系统。首先给出了系统的总体设计框架,详细介绍了硬件设计和软件设计方法。设计时采用了模块化的方法,对ARM模块、FPGA模块及接口连接部分进行分别设计。ARM模块实现了USB和以太网双接口。用FPGA设计1553B协议IP核采用自顶向下的方法。同时,也对外围电路和电源模块进行了优化设计。完成设计后进行了仿真验证,结果表明设计实现了接收与发送功能,符合设计要求。最后,在电路板上进行了实际调试,测试取得了良好的效果,能够满足实际应用要求。     

基于FPGA的高速收发器研究与设计

在数字系统设计领域,对带宽的需求在不断增长,数据的并行传输已经成为高速数据传输的瓶颈,新一代高速串行总线技术如PCI Express、USB3.0、SATA等技术日臻成熟,而高速收发器是实现串行高速数据传输系统的重要组成部分.解析高速收发器的基本结构、工作原理,分析了总体设计、各模块的详细设计以及在FPGA中的集成,并进行了仿真和验证,研究表明采用高速收发器可以实现FPGA串并转换数据的功能.     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.