无线传感器网络路由协议性能研究

无线传感器网络是目前网络研究的热点,其路由协议的设计是最具挑战性的问题之一,对目前典型的无线传感器网络的路由协议进行分类研究和性能分析,设计并实现了在NS2环境下典型协议的仿真场景和性能分析比较。对无线传感器网络路由协议的研究和组网具有参考指导意义。     

基于微功率无线通信技术的电冰箱能效试验系统的设计（上）

传统的电冰箱能效试验采用的热电偶连接线必须跨越冰箱门才能连接到温度记录仪上,这样必定在冰箱门处产生细小的缝隙,从而影响了间室的密封性,使检测的结果出现误差。该文介绍了一种利用微功率无线通信技术开发的新型检测系统,避免了此类误差的产生,并阐述了该系统的工作原理和软硬件结构。实际应用证明,该系统各方面性能良好,测量数据准确...     

摩擦试验机数据采集与处理系统设计

基于摩擦试验机对计算机采集与处理数据功能的要求,采用串口通信方法,结合VB语言编程,设计了试验机的数据采集卡和数据处理系统。实验测试表明,该数据采集和处理系统能完成摩擦信号的实时动态采集、实时数据处理和数据动态显示。系统工作可靠,测试数据准确。     

Quantum Pseudo-Telepathy

Quantum information processing is at the crossroads of physics, mathematics and computer science. It is concerned with what we can and cannot do with quantum information that goes beyond the abilities of classical information processing devices. Communication complexity is an area of classical computer science that aims at quantifying the amount of communication necessary to solve distributed computational problems. Quantum communication complexity uses quantum mechanics to reduce the amount of communication that would be classically required. Pseudo-telepathy is a surprising application of quantum information processing to communication complexity. Thanks to entanglement, perhaps the most nonclassical manifestation of quantum mechanics, two or more quantum players can accomplish a distributed task with no need for communication whatsoever, which would be an impossible feat for classical players. After a detailed overview of the principle and purpose of pseudo-telepathy, we present a survey of recent and not-so-recent work on the subject. In particular, we describe and analyse all the pseudo-telepathy games currently known to the authors. Supported in Part by Canada’s Natural Sciences and Engineering Research Council (NSERC), the Canada Research Chair programme and the Canadian Institute for Advanced Research (CIAR). Supported in part by a scholarship from Canada’s NSERC. Supported in part by Canada’s NSERC Québec’s Fonds de recherche sur la nature et les technologies (FQRNT), the CIAR and the Mathematics of Information Technology and Complex Systems Network (MITACS).     

红外无线多机共享打印机接口卡

利用红外通信技术，假脱机打印的特点，实现了无线多机共享一台打印机的接口功能，从而有效地解决了传统的有线共享打印机接口带来的诸多不便，省去多台计算机共享一台打印机转接线的麻烦，提高打印机的使用效率。     

基于JUMMSE准则的前向分数间隔判决反馈均衡器

研究了前向分数间隔判决反馈均衡器的原理与结构,并推导了基于联合无偏差MMSE(JUMMSE)准则设计的最优解。文中讨论了均衡器长度对误符号率(SER)性能的影响。仿真结果表明,在较高的信噪比、选择恰当的均衡器长度时,这种均衡器对于高频信道的均衡效果是显著的。     

高速移动数据传输新标准IEEE 802.20

介绍了未来高速移动通信新标准IEEE802．20的总体概况,具体分析了IEEE802．20的技术特性、系统参考结构以及系统的组成模型,并对IEEE802．20标准前景分析与展望进行了详细描述。     

民用房屋改造成移动通信机房应注意结构的安全

通过工程调查发现，一些民用房屋改造成移动通信机房过程中由于设备布置不当，对结构构件的安全产生严重的影响，针对一具体问题进行楼板承栽力计算分析并提出相应的处理措施，供设计人员探讨。     

无线Mesh网络跨层路由技术研究

无线Mesh网络(WMN:wireless mesh networks)作为一种新型的无线网络,成为近几年研究的热点。由于无线信道不稳定等特性,如何设计WMN的路由协议成为决定其性能的关键因素之一。近几年来的研究表明,通过跨层设计的方式综合其他层的重要参数来实现路由选择,能够很好地解决这一难题。介绍了几种先进的跨层路由设计方案,总结了现有的跨层路由协议的优缺点,并对如何设计并实现跨层路由协议进行了分析和总结。     

Queue Analysis and Multiplexing of Heavy-tailed Traffic in Wireless Packet Data Networks

Recent research based on traffic measurements shows that Internet traffic flows have a fractal nature (i.e., self-similarity property), which causes an underestimation of network engineering parameters when using the conventional Poisson model. Preliminary field measurements demonstrate that packet data traffic in wireless communications also exhibits self-similarity. In this paper, we investigate the queuing behavior of self-similar traffic flows for data applications in a packet-switching single-server wireless network. The traffic is generated by an on–off source with heavy-tailed on periods and exponentially distributed off periods. We extend previous analysis of a relation among the asymptotic distribution of loss probability, traffic specifications, and transmission rate for a wireline system to a wireless system, taking into account wireless propagation channel characteristics. We also investigate the multiplexing of heavy-tailed traffic flows with a finite buffer for the downlink transmission of a wireless network. Computer simulation results demonstrate that assumptions made in the theoretical analysis are reasonable and the derived relationships are accurate.