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1.
许多研究表明,优秀的分簇路由算法能够有效的延长传感器网络的使用时间。在分析典型的分簇路由算法LEACH存在问题的基础上,提出了基于位置信息的低能耗路由算法,该算法在LEACH算法的簇头选取机制上进行了改进,综合考虑了位置和能量等信息,仿真实验表明,新算法较LEACH算法能更好的降低能耗,均衡网络能量,延长网络使用时间。  相似文献   

2.
许多研究表明,优秀的分簇路由算法能够有效的延长传感器网络的使用时间。在分析典型的分簇路由算法LEACH存在问题的基础上,提出了基于位置信息的低能耗路由算法,该算法在LEACH算法的簇头选取机制上进行了改进,综合考虑了位置和能量等信息,仿真实验表明,新算法较LEACH算法能更好的降低能耗,均衡网络能量,延长网络使用时间。  相似文献   

3.
高动态无线自组网路由协议设计   总被引:1,自引:1,他引:0  
王文弢  卿利 《电讯技术》2012,52(5):804-807
针对节点快速移动过程中网络建立时间较长,数据端到端传输时延无法得到可靠保 障,并且由于维护动态网络连接性造成网络开销较大等方面的问题,提出了一种无线自组网 路由协议,通过分簇算法快速将网络分为多个簇,每个簇包括簇首节点、成员节点和簇间网 关节点。该协议能够应用于快速移动节点构成的高动态无线自组织网络中,实现了先应式和 反应式路由算法进行了有机结合,能够在快速变化的拓扑结构中为未知路由提供优化的路由 结果,利用较小的网络开销实现网络快速构建和数据端到端的实时传输。  相似文献   

4.
在无线传感器网络中的LEACH协议是一种自适应聚类路由算法.由于LEACH协议存在着无法控制簇首在网络中的分布位置、簇首选择方式限制条件不够等缺点导致能量消耗太大.基于簇头能量限制和双簇头路由方式,对LEACH协议进行了改进,设计了一种降低能耗的双簇头非均匀分簇路由协议.双簇头非均匀分簇路由协议采用NS2进行网络仿真实验,通过仿真结果的分析以及与LEACH协议的对比,证明双簇头非均匀分簇路由协议有效提高了网络能耗的均衡性.  相似文献   

5.
无线传感器网络能量均衡路由算法   总被引:5,自引:3,他引:2  
设计了一种能量均衡的路由算法.路由的建立分两个阶段,在簇头建立阶段,让候选节点在覆盖范围内以剩余能量的多少和所处位置为标准来竞选簇头,以使簇头分布均匀,平衡网络覆盖;在通信阶段,根据簇头节点的剩余能量大小和其距离基站的远近,采用多跳的簇间通信方式建立路由,以此来降低簇头节点的通信负载.仿真结果表明该算法能够有效降低网络能耗和延长网络生存时间.  相似文献   

6.
在无线传感器网络中,一种合理的路由算法对提高网络寿命有着非常重要的作用,基于传统的分簇路由协议LEACH,以延长网络寿命和提高网络通信质量提出了一种新的路由算法.这种路由算法引入了有向天线的使用.算法在定向传播的基础上不但节省了网络能量,并且灵活的簇群配置,簇头交换策略使得这个新的算法不局限于特定拓扑分布无线传感器网络.算法的创新点在于利用天线的方向形成簇群,同时达到了在数据传输时能量节省和网络路由变化通信开销减少的目的.  相似文献   

7.
无线传感器网络(WSN)作为物联网中非常重要的一个环节,其网络层协议负责路由发现和维护,网络层路由协议的好坏直接影响到整个网络的性能。本文基于传感器网络的剩余能量以及簇头节点能量的变化,针对经典的LEACH协议进行改进,提出新的簇头选择算法,通过仿真,结果表明本文提出的改进能够达到优化网络性能的目的。  相似文献   

8.
无线传感器网络(WSN)路由协议研究的一个重要的目标是如何在有限的能源下降低整个网络的能耗,提高网络的生存时间。以分簇路由协议LEACH为研究基础,提出了一种改进算法。该算法改进了簇首选择规则,引入协调件协议算法,通过在成簇阶段降低剩余能量低的节点被选择成为簇首的概率,在稳定运行阶段使簇首节点尽可能多的保持睡眠状态,从而降低了网络能耗。仿真结果表明,与原LEACH算法相比,改进的算法能够明显地延长网络生存时间。  相似文献   

9.
提出了一种网关辅助的渐进式分簇路由算法。该算法在渐进式的分簇路由协议(AODV-clustering)的基础上,结合GORP协议,通过增加网关的功能,使网关在路由的发现和维护以及数据传送中分担簇首的部分工作,从而降低簇首节点成为网络瓶颈的可能性。仿真结果表明,该算法既保持了AODV-clustering的优点,且进一步缩短了路由建立的时间,提高了数据报文发送成功率。  相似文献   

10.
无线传感器网络能量均衡分簇路由协议   总被引:1,自引:0,他引:1  
LEACH是无线传感器网络(Wireless Sensor Network,WSN)中一种经典的分层式路由协议,在此基础上通过对LEACH成簇算法及簇间路由的改进,提出了一种新的均衡能量消耗分簇路由协议。该协议在无线传感器网络成簇过程中充分考虑了传感器节点的能量状态,同时簇首向基站的通信采用基于能量的簇间路由。理论分析及仿真结果表明,改进的协议能够均衡传感器节点的能量消耗,有效地延长网络寿命。  相似文献   

11.
DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.  相似文献   

12.
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   

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.
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   

15.
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   

16.
This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel's.  相似文献   

17.
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   

18.
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   

19.
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   

20.
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   

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