基于FPGA的激光陀螺信号高速精确解调系统

利用FPGA的高度并行性和对时延的准确控制,设计对激光陀螺信号的高速、精确解调系统。该系统以XILINX FPGA为硬件核心,通过巧妙的时钟设计和高速高阶滤波设计,很好地实现了对陀螺信号精确鉴相、计数和高速滤波,并协调DSP的后续处理和上位机通信。通过对国产某激光陀螺进行测试发现,本系统解调后得到的陀螺角速度10S、100S的方差都明显优于现有系统的测试结果,系统响应时间也得到极大提高。     

基于FPGA的激光陀螺信号高速解调滤波设计

在FPGA中实现DSP和计算机常用的IEEE单精度32位浮点表示方式,通过模块化设计,能够进行相关的浮点加法和乘法操作。利用内部逻辑单元、乘法器、ROM、RAM等资源,经过正确的逻辑控制和可靠的时序设计,设计了一个能对激光陀螺信号进行高速、精确滤波的专用滤波器,并且更简便实现后续DSP或计算机对滤波数据的格式处理。     

基于FPGA的程控滤波器设计与实现

设计一个由现场可编程门阵列(FPGA)控制的滤波器。该滤波器主要由3个模块组成:前置放大、滤波电路、FPGA显示与控制电路等利用FPGA作为放大器及程控滤波器电路中继电器组的控制模块,实现了可编程放大参数的设置以及低通和高通滤波截止频率的数字控制。基于FPGA技术,使得该系统具有抗干扰能力强,可靠性好等优点。对系统进行了测试,结果表明符合设计要求。     

基于FPGA的抖动偏频激光陀螺高精度信号解调

分析了抖动偏频激光陀螺信号的解调原理，提出了一种利用数字信号处理技术并采用FPGA实现的抖动解调方法；通过对激光陀螺脉冲计数值高速采样并采用数字滤波器滤波处理，可以有效消除抖动引起的信号噪声，得到所需的惯性角速率测量信息；增加数字预滤器，以滤除陀螺脉冲输出信号中的尖峰或毛刺干扰，可以进一步提高解调精度；为满足实时性要求，该方法采用FPGA来实现；实验表明，相对整周期采样解调，此方法提高了解调精度。     

罗兰C前端数字带通滤波器设计与实现

分析了罗兰C信号的特征,并根据信号特征决定选用FIR滤波器,利用MATLAB工具设计了满足滤波要求的高阶数字带通滤波器。详细研究了分布式算法的原理和分布式算法在FPGA上实现FIR数字滤波器的方法。最终采用改进的分布式算法在FPGA上实现了127阶FIR数字带通滤波器。利用实际采集的信号进行仿真和现场测试,结果均显示由该方法设计的滤波器性能良好,方法简单易行,相对于传统的乘累加结构不仅能节省硬件资源,而且可以改善数据处理速度,具有一定的推广价值。     

二频机抖激光陀螺高精度低延时信号解调电路设计

在激光陀螺信号解调滤波过程中,工程上经常运用高阶FIR滤波电路来实现抖动信号剥除;这种方法虽然精度高但具有较高的延时,无法满足激光陀螺输出结果实时性的要求;为了解决这个问题,提出了一种基于FPGA的激光陀螺信号解调电路,利用自适应滤波原理对激光陀螺输出抖动信号进行自适应剥除,最后进行了相应精度及延迟测试;实验结果表明激光陀螺信号经过该系统自适应抖动剥除后效果较好,激光陀螺静态输出百秒方差仅为千分之三且系统延迟0.6 ms远低于常规5 ms延迟,满足了激光陀螺信号解调高精度低延时的要求。     

FIR数字滤波器设计及其FPGA实现

以FPGA为硬件平台,利用FPGA的DSP开发工具DSP Builder对数字滤波器进行建模设计及系统模型仿真,生成VHDL工程文件,编制相应顶层文件,使其符合滤波器硬件系统。利用QuartusⅡ对项目进行综合、编译和调试,生成原理图模块和RTL电路图。通过对5 kHz方波信号进行仿真滤波,并将VHDL下载到硬件系统中进行硬件实现,有效地提取到5 kHz的正弦信号。实验结果表明,该设计很好地达到了FIR滤波器的性能,为数字滤波器的设计与实现提供了新的途径和方法。     

一种基于电力系统保护的模型化数字滤波器的设计

提出了基于FPGA的新型电力载波继电保护系统的滤波器设计方法,充分利用FPGA的优势,设计了一种高性能的IIR滤波器,在FPGA中加以实现.仿真结果表明,所设计的滤波器具有速度快、滤波效果好、修改灵活等优点.     

数字下变频中抽取滤波器的设计及FPGA实现

针对软件无线电接收机数字下变频中高速数字信号的降采样需求,利用半带滤波器及级联积分梳状滤波器,设计了一种半带滤波器前置的多级抽取滤波器架构。通过Simulink搭建系统模型验证之后,利用Xilinx ISE 12.3在Xilinx xc5vsx95t-2ff1136 FPGA上实现了一种下采样率为64的抽取滤波器。Modelsim仿真结果表明,该抽取滤波器设计是有效的,达到了设计指标。     

高速上下变频FIR滤波器的FPGA设计

针对宽带WLAN收发器要求，在单片FPGA上设计实现了高速数字上下变频器和滤波器，其中滤波器为80MHz的40阶FIR滤波器，可以设定工作在上变频或下变频方式。为了对FPGA的资源占用量最小，以便实现片上系统(SoC)设计，充分利用了上下变频过程中I，Q数据流的特点，仅用一套滤波器运算单元分时复用对I，Q滤波，同时详细研究了滤波器的转置结构和位平面结构对FPGA资源占用量的差别。结果表明，位平面结构对逻辑资源的占用量仅是转置结构的一半。在FPGA上用位平面结构实现高速滤波器在资源占用量方面有明显优势。     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

Call for Papers The 6^th International Conference on Grid and Cooperative Computing

Recent years have seen rapid advances in various grid-related technologies, middleware, and applications. The GCC conference has become one of the largest scientific events worldwide in grid and cooperative computing. The 6th international conference on grid and cooperative computing (GCC2007) Sponsored by China Computer Federation (CCF),Institute of Computing Technology, Chinese Academy of Sciences (ICT) and Xinjiang University ,and in Cooperation with IEEE Computer Soceity ,is to be held from August 16 to 18, 2007 in Urumchi, Xinjiang, China.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.     

The Distributed Time-Triggered Simulation Scheme: Core Principles and Supporting Execution Engine

Distributed real-time simulation is a young technology field but its practice is under increasing demands. In recent years the author and his collaborators have been establishing a new approach called the distributed time-triggered simulation (DTS) scheme which is conceptually simple and easy to use but widely applicable. The concept was initiated in the course of developing a new-generation object-oriented real-time programming scheme called the time-triggered message-triggered object (TMO) programming scheme. Some fundamental issues inherent in distributed real-time simulation that were learned during recent experimental studies are discussed along with some approaches for resolving the issues. An execution engine developed to support both the TMOs engaged in control computation and the TMOs engaged in DTS is also discussed along with its possible extensions that will enable significantly larger-scale DTSs.     

Software-Konfigurationsmanagement in großen Softwareprojekten

Zusammenfassung Mit zunehmender Größe der Softwaresysteme verschärfen sich die für die Software-Herstellung typischen Probleme: Beherrschen großer Objektmengen, Erhalten der Systemkonsistenz, Kontrolle der ständigen Änderungseinflüsse und Gewährleisten einer langen Lebensdauer. Die Disziplin Konfigurationsmanagement bildet den methodischen Ansatz, diese Probleme besser zu beherrschen. Software-Konfigurationsmanagement faßt die Herstellung von Softwaresystemen als eine Abfolge von kontrollierten Änderungen an gesicherten Zwischen- und Endergebnissen auf. Dargestellt werden die Objekte und Funktionen des Software-Konfigurationsmanagements sowie die hierfür in großen Software-Projekten benötigten Methoden, Instanzen und Hilfsmittel.     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and     

Editorial:Brain-machine interface(BMI) and cyborg intelligence

正Brain-machine interfaces(BMIs)aim at building a direct communication pathway between the brain and an external device,and represent an area of research where significant progress has been made during the past decade.Based on BMIs,mind information can be read out by neural signals to control     

Information for Authors

正http://www.zju.edu.cn/jzus http://www.springerlink.com Aim The Journals of Zhejiang University-SCIENCE(A/B/C)are edited by the international board of distinguished Chinese and foreign scientists,and are aimed to present the latest developments and achievements in scientific research in China and overseas to the world’s scientific circles,especially to stimulate     

SCIENCE CHINA Information Sciences SUBJECT INDEX TO VOLUME 57(2014)

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