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1.
ZigBee网络混合路由算法(ZigBee Routing,ZBR)中将源节点和目的节点之间的最小跳数作为唯一的路由度量因素.但随着节点能量消耗以及节点的频繁移动,ZBR算法的这一特性会造成网络间歇性连接,从而导致网络性能下降.提出一种选择最优分组转发路径的ZigBee网络混合路由算法(Grey Relational Algorithm based ZBR,GRA-ZBR).GRA-ZBR算法在目的节点选择路径时引入灰色关联算法,综合考虑节点剩余能量、链路质量、节点剩余队列长度以及路径长度等因素.仿真结果表明,GRA-ZBR算法可以有效提高网络分组投递率,降低平均端到端时延.  相似文献   

2.
基于节点特性的LR-WPAN网络能量优化路由算法   总被引:3,自引:0,他引:3  
针对ZigBee网络混合路由算法的不足,考虑低速无线个域网(LR-WPAN)网络的能耗问题,提出了一种基于ZBR路由协议的改进算法(F-ZBR).本算法通过定义最小路由能量值和控制路由请求分组(RREQ)的传输方向、跳数以及在RREQ分组中加入能量标志位等措施,降低网络的整体能耗.仿真结果表明,F-ZBR算法的分组投递率、网络可用节点比率和网络剩余能量都较ZBR有明显提高,从而可以延缓ZigBee网络中大量数据传输造成的RN+节点能量过度损耗而导致的网络瘫痪等问题的发生,延长网络生命周期.  相似文献   

3.
《现代电子技术》2016,(8):68-71
为解决ZigBee网络由于不合理的路由策略导致节点能量浪费和网络陷入局部死亡的问题,提出一种降低节点能量开销的ZBR路由算法。所提ZBR优化算法在路由发送阶段,利用节点自动维护的邻居表信息,优先实现两跳路由传输;在路由发现过程中,根据最大传输跳数和节点间的父子关系,控制ZigBee网络中RN+节点RREQ分组的洪泛,减少能量浪费;在路由选择时,设计节点能量标志位和能量感知的路由成本函数,减少能量偏低节点的使用概率,降低网络开销和提高节点生存率。通过与原ZBR算法及其他几种改进ZBR算法进行剩余能量和节点生存率对比仿真实验,结果表明:改进的ZBR算法的平均剩余能量提高了7.74%,在网络运行80s时节点生存率提高了20.29%,也高于其他几种改进ZBR算法,该算法可有效减少网络能量消耗,大大提高节点生存率。  相似文献   

4.
针对目前ZigBee网络混合路由算法寻找开销偏大、能耗不均的问题,提出一种高效混合路由算法( EHCA)。通过采用跨层泛听与优先使用深度大、剩余能量多的节点进行路由的方式,减少部分泛洪寻路分组的转发,均衡节点能耗。仿真结果表明,EHCA的节点能耗均衡、路由开销和网络寿命等性能均优于混合路由算法和树路由算法。  相似文献   

5.
针对ZigBee网络多路径分层树路由算法(Z-MHTR)存在网络开销过大,路径建立机制不够优化等问题,提出一种基于树路由的高效多路径路由算法Z-EMR(ZigBee Efficient Multipath Routing).Z-EMR算法在多路径建立过程中减少了寻路数据分组的发送个数,并且删除了树路径的重复发现过程,从而使得算法变得更加高效.仿真结果表明,与Z-MHTR算法相比,Z-EMR算法有效地降低了网络开销,减少了路径平均长度和平均端到端时延,达到了路径优化和提高ZigBee网络整体性能的目的.  相似文献   

6.
按需路由协议AODV的路由发现使用洪泛方式的扩散法,导致网络超负荷运行和拥塞,而且在选择转发路由时,总是选择最少跳数的路由,造成无线传感网络中节点能量不均,减少网络寿命.本文提出了AODV-DE算法,该算法引入广播域的概念,限制RREQ分组的转发范围,同时避免使用剩余能量低的节点转发数据分组,选择路由路径时选择总剩余能量最多的路径进行信息的传送.仿真结果表明,AODV-DE协议在路由开销、网络寿命和端到端的延迟这三个方面表现出了优势.  相似文献   

7.
ZigBee网络技术是一项新兴的低成本、低功耗的短距离无线通信技术,在智能家居中有广阔的应用前景。介绍了智能家居中ZigBee的通讯协议和网络地址分配方法,并针对传统的AODVjr路由算法在路由过程中RREQ分组过量洪泛问题和Cluster-Tree算法只按父子关系选择路由问题,提出了一种改进路由算法。改进算法将AODVjr和Cluster-Tree算法相结合,引入邻居表,适当控制RREQ转发方向,并考虑节点最小剩余能量。仿真结果表明,改进算法可以减少路由开销,延长节点的生存时间,均衡网络负荷。  相似文献   

8.
ZigBee网络中的AODVjr算法通过全网广播路由请求RREQ消息而获得分组发送的最短路径,但节点大量广播RREQ消息增加了网络控制开销,导致网络节点耗能剧增,同时网络堵塞的可能性也大大提升。针对AODVjr算法存在的网络节点耗能剧增问题,在AODVjr算法基础上,结合节点邻居表,提出筛选RREQ消息转发节点,从而限制RREQ消息转发次数的路由算法Zig Bee树节点自剪裁转发算法(ZigBee On-tree Self-pruning Rebroadcast Algorithm,ZOSR)和ZigBee转发节点选择算法(ZigBee On-tree Forwarding Node Selection Algorithm,ZOFNS)。仿真结果表明,算法能有效降低网络节点的转发次数,从而降低网络整体功耗,延长网络工作时间。  相似文献   

9.
针对移动Ad Hoc网络中节点任意移动、网络拓扑频繁变化导致以最小跳数作为路由选择机制的AODV路由协议面临频繁连接中断而造成网络QoS下降的问题,文章综合节点的剩余电量、剩余队列长度和源节点到目的节点的跳数三个跨层信息,提出一种基于灰色关联算法的改进AODV路由协议(GRA-AODV)。仿真结果显示:相比于改进前的AODV协议,改进之后的GRA-AODV(Gray Relevance AlgorithmAODV)协议在稍微增加路由开销的情况下,具有更低的平均端到端时延和更低的分组丢失率,在拓扑频繁变化的移动Ad Hoc网络中具有较好的鲁棒性。  相似文献   

10.
杨璐 《电子科技》2014,27(3):12-14,17
通过对ZigBee中的Cluster-Tree算法以及对AODVjr中的路由发现进行研究,在Cluster-Tree邻居表的基础上提出捷径路由,从该节点周围的邻居节点中找出可以用少量跳数即可到达目的节点。此后通过路由代价函数,计算通过Cluster-Tree改进算法中找到节点路径的能量使用代价,选择可靠性较高的路径,从而可以延长网络生存周期和降低能耗。最后通过实例,验证了算法改进的可行性。  相似文献   

11.
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.  相似文献   

12.
The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.  相似文献   

13.
The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.  相似文献   

14.
Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.  相似文献   

15.
A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.  相似文献   

16.
A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.  相似文献   

17.
Call for Papers     
正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks  相似文献   

18.
正Information Centric Networking Information-Centric Networking(ICN) is an emerging direction in Future Internet architecture research,gaining significant tractions among academia and industry.Aiming to replace the conventional host-to-host communication model by a data-centric model,ICN treats data content as the first  相似文献   

19.
20.
LI Shaoqian 《中国通信》2014,(6):I0001-I0002
The global bandwidth shortage of wireless communications has motivated the exploration of the naillimeter wave (ram-wave) frequency spectrum for the next generation wireless communications. Recent advances in RF CMOS technology and high speed baseband signal processing technologies have enabled tile extensive research and development of turn-wave wireless communications. The multi gigabit per second data rate of ram-wave system will lead to applications in many important scenarios, such as WPAN, WLAN,back-haul for cellular system. And the frequency bands include 28 GHz, 38 GHz, 45GHz, 60GHz, E-BAND and even beyond 100 GHz. The propagation and the imitation of the RF circuits design in these frequency bands make the directional antennas be inevitable for mm-wave communications.  相似文献   

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