工业以太网变送器的一种简易实现方法

作为标准以太网协议在工业过程控制系统中的延伸，工业以太网协议已被IEC列入现场总线标准并发布，得到了迅速的发展和应用。基于各种工业以太网协议的现场设备也成为了研究的重点。介绍了一种基于MC9S12NE64微处理器的变送器系统，利用其集成的以太网模块、μC／OS—Ⅱ嵌入式操作系统和公开代码TCP／IP协议栈，以较低的价格和功耗，满足工业以太网总线协议。     

进入以太网，退出现场总线吗

正当现场总线处于稳定时期时,以太网进入了工业网络领域。有人认为它是一种威胁,有人却认为它不够工业化而不必重视它。Rob Hulsebos先生在本文中就以太网与现场总线协议栈的融合以及现场总线系统是否值得对此担忧等方面进行了探讨。     

创新的多协议现场无线网络——多种无线通信标准的融合

国际电工委员会先后批准了三个过程自动化行业的无线通信标准:WirelessHART、WIA-PA和ISA 100. 11a。用户曾寄希望这三个标准能够统一。虽然标准一时无法统一,但能够做到互相融合,比如说在单一架构下管理多个无线通信标准网络的实时数据。阐述了过程自动化行业无线通信标准融合的方式、可能性以及融合技术的发展现状。虽然由国际自动化学会及用户组织对过程自动化行业无线通信标准统一所做工作没达到预期目标,但来自制造商的下述工作可以看成是过程自动化行业无线通信标准融合技术获得突破的一个标志:美国尼维斯(Nivis)公司的双启动硬件、双栈无线通信模块和双栈接入点,爱默生过程管理公司的双模无线网关,霍尼韦尔公司的多协议、多应用、多标准现场无线网络。这些工作同时也证明在标准的融合方面,无线通信标准走在了现场总线的前面。     

FF HSE协议栈软件的设计与实现

介绍了现场总线基金会高速以太网FF HSE协议栈软件的设计与开发过程。根据HSE规范所规定的系统体系结构来划分软件模块和分配任务。开发中采用增量式迭代开发方法和交叉开发工具。通过对现场设备进行组态的实验表明，所开发的协议栈软件设计合理、方法可行。     

基于HSE的时间同步及其实现

介绍了现场总线基金会高速以太网(HSE)，在详细描述了简单网络时间协议(SNTP)的工作原理的基础上，同时给出了基于有线和无线通信的时间同步源程序。     

一种低成本嵌入式互联系统的设计与实现

为了在不改变原有网络结构的情况下，将现场总线控制系统改造为基于以太网的分布式控制系统，研发了基于ARM体系结构的STR912FW44嵌入式微控制器的低成本嵌入式CAN-Ethernet网关。STR912FW44采用ARM966E-STM内核，集成了以太网控制器和CAN总线控制器。该嵌入式CAN-Ethernet网关采用嵌入式TCP/IP协议栈与以太网中的设备进行通信，并利用STR912FW44集成的CAN控制器与CAN总线上的终端进行通信。在通信过程中，STR912FW44进行TCP/IP协议和CAN协议之间的转换。经现场验证，该网关较好地完成了两种网络之间的协议转换和数据通信。     

基于工业以太网实时协议的改进

介绍了一种基于工业以太网的实时协议，参考Profibus DP现场总线技术，基于以太网数据链路层的逻辑链路控制子层提出了一种改进方案，在以太网上实现了Profibus DP的基本功能，使以太网适应实时通信的要求和能够应用于设备级，并且与已经存在的Profibus DP现场总线上的应用保持了连续性和兼容性。最后介绍了协议的实现和性能分析。     

基于EPA标准的无线通信技术的应用研究

本文介绍了具有自主知识产权的《基于以太网的工业现场网络通信协议标准》,即《EPA标准》,并在EPA网络体系结构的基础上,讨论和分析在EPA网络中应用无线通信技术的可行性和方法,对实现无线设备通信的安全提出了建议。     

基于Linux的现场总线无线通信卡的实现

本文阐述了基于Linux的现场总线无线通信卡的实现过程,成功地解决了IO模块控制卡与其之间的通信问题,通过无线通信卡实现了无线现场设备通过标准的无线技术接入到现有的现场总线中。同时进行了简单测试,实验证明测试系统运行效果良好,达到了预期目标。     

基于以太网的新型嵌入式远程控制系统

随着信息与网络技术的发展，嵌入式系统渗透到各个领域，得到了广泛的应用。CAN总线作为一种优秀的现场总线．和以太网连接起来即可大大提高控制系统的分布式特性。本文以高速的ARM处理器LPC2290为核心，设计了一套基于以太网和CAN嵌入式系统的核心控制部分，研究了TCP／IP协议栈的组成和内部实现原理，完成了μC／OS—Ⅱ操作系统下CAN—TCP／IP应用程序，实现CAN数据和以太网数据的双向稳定传输。     

A provably secure authenticated key agreement protocol for wireless communications

Designing elliptic curve password-based authenticated key agreement (ECPAKA) protocols for wireless mobile communications is a challenging task due to the limitation of bandwidth and storage of the mobile devices. Some well-published ECPAKA protocols have been proved to be insecure. We notice that until now none of the existing ECPAKA protocols for wireless mobile communication is provided any formal security analysis. In this paper, we propose a novel protocol and conduct a formal security analysis on our protocol. Compared with other ECPAKA protocol, our protocol meets all basic security properties and is the first ECPAKA protocol with formal security proof for wireless communication. We also explore the suitability of the novel protocol for 3GPP2 specifications and improve the A-Key (Authentication Key) distribution for current mobile cellular systems.     

浅谈无线通信Zigbee技术

通信技术在新世纪新形势下的迅猛发展,用户的需求逐步增长,许多新的无线通信协议应运而生。当前,人们主要应用的无线通信技术包括Zigbee技术、红外数据传输(IrDA)、蓝牙技术、无线局域网802.11(WiFi),同时还有短距离通信(NFC)、超宽频(Ultra WideBand)、无线1394和专用无线系统等一些具有发展潜力的无线技术标准。本文对于无线通信技术Zigbee技术进行了研究。     

A survey on ultra wide band medium access control schemes

Ultra wideband (UWB) technology based primarily on the impulse radio paradigm has a huge potential for revolutionizing the world of digital communications especially wireless communications. UWB provides the integrated capabilities of data communications, advanced radar and precision tracking, location, imperceptibility and low power operation. It is therefore ideally suited for the development of robust and rapid wireless networks in complex and hostile environments. The distinct physical layer properties of the UWB technology warrants efficient design of medium access control (MAC) protocols. This paper introduces the unique UWB physical characteristics compared to the existing wireless technologies and discusses current research on MAC protocols for UWB. This report surveys most of the MAC protocols proposed so far for UWB, and may instigate further activities on this important and evolving technology.     

The anatomy study of server-initial agreement for general hierarchy wired/wireless networks

The Byzantine Agreement (BA) plays a key role in fault-tolerant distributed system design. A number of solutions to the BA problem based on various network model assumptions have been proposed. However, most existing BA protocols are designed for pure wired or pure wireless networks. In practice, most current networks are combined wired and wireless environments. In this paper, we extend the BA problem over a combined wired/wireless network, consisting of both powerful computing stationary processor and low-power mobile processor. The communication overhead of BA protocol is inherently large and secure group communications are important. The protocols proposed in this paper use the hierarchical model concept to reduce the communication overhead and provide secure group communications well suited for combined wired/wireless networks.     

Driving into Intelligent Spaces with Pervasive Communications

Recent advances in digital modulation and transmission, signal processing, wireless access protocols, and IC technology have spawned many intelligent devices and objects. A good example are intelligent transportation spaces (ITSP) which have shown many potential benefits including driving safety, transport efficiency, and comfort that accrue from increased traffic information, reduced driving loads, and improved route management. Although wireline communications might enable some ITSP requirements, the inherent mobility, flexibility and scalability of wireless communications clearly make them critical. Enabling technologies in this area include an array of wireless solutions such as ISM bands, DSRC bands, UWB radio, and MAC protocols     

基于蜂窝无线网络的移动IP(IPV6)研究

介绍了基于IPv6技术的TCP／IP协议与蜂窝无线通信网络结合的方法和技术。从框架、体系结构、协议实现各个角度分析了这两种技术结合的切入点和技术关键。3G蜂窝无线通信技术是当今一大研究热点，移动IP技术是今后网络的发展方向，从实用的角度为移动通信技术提出了新的观点和方法。     

一种基于ARM7的GPRS无线通信实现

针对GPRS无线通信问题,提出一个从硬件设计到软件控制实现的整体方案。在该方案中,给出GPRS模块与ARM7之间的硬件连接电路图,解决GPRS模块驱动,分析GPRS通信协议,制作GPRS测试的上位机界面,实现GPRS无线通信。实验结果表明,所提出来的方案正确、可靠。     

Carla: A rule language for specifying communications architectures

Due to the unique requirements of a series of projects to specify communications architectures using graphical representations (Cara and MFD), we have developed the communications-oriented rule-based language Carla (Cara Rule Language), which provides an executable specification of the architecture being developed. Carla is designed to provide the ability to specify and simulate high-level, possibly incomplete, specifications of communications architectures, and to allow the developer to refine the specification through the addition of behavior-describing rules. Carla is also well-suited to creating black-box specifications of any system whose behavior depends on input/output history. We describe the features of the language, discuss various design issues, and provide examples of various communications protocols specified in Carla.     

提高业务技能对无线列调设备维护的重要性

铁路列车无线调度通信系统是保障铁路运输生产的重要通信设施.作为专业维护人员.必须熟练掌握无线列调通信系统的相关知识,分析解决设备运用中存在隐患与缺陷,保障无线列调通信随时畅通,同时还要不断学习新知识.新技术,适应铁路无线通信系统的不断更新和发展.为更好地维护无线列调系统作贡献.     

MANET中MAODV与ODMRP组播路由协议的研究与分析

MANET是非基础结构无线网络的典型代表,具有带宽有限、拓扑结构易变和电池能源有限的特点,这些特性使得未来集成网络实现组播通信具有一定的挑战性。该文首先介绍了MANET组播路由协议MAODV和ODMRP,然后对两种协议进行了比较分析,并得出结论。