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1.
As an important field of emerging technology, wireless sensor networks (WSN) offer many new possibilities for applications such as target tracking and environmental surveillance by allowing the observer to move around freely. However, disseminating sensing data to the mobile observer raises significant design challenges for the routing scheme. In addition, WSN often operate under certain energy constraints, and therefore reducing energy dissipation in order to prolong the lifetime of the WSN is another challenge that must be faced. Most proposed routing protocols focus on achieving effective data dissemination and energy efficiency at the same time as working to satisfy the requirements of the mobile observer. However, almost all of these methods use frequent rerouting as a way of handling the mobility issue. Such rerouting increases both overheads and energy consumption, resulting in a trade-off between the need for rerouting to optimize network operations and that of maximizing network lifetime. This paper presents the Energy-aware Grid-based Routing Scheme (EAGER) for WSN with mobile observers, which is an approach that seeks to save more energy in the context of dynamic topology. In this paper, EAGER is compared to other proposed grid-based schemes by using extensive simulations. These simulations clearly show that EAGER outperforms other grid-based schemes in terms of both energy efficiency and routing performance.  相似文献   

2.
路由设计是认知无线传感网络(CRSNs)中目前受到较少关注却很重要的一个领域。在CRSN中,由于主用户(PUs)对可用信道资源的随机占用行为,路由算法的设计不仅需要考虑如何延长网络寿命,还要考虑网络内数据传输的可靠性。本文研究了具有频谱可感知特性,且对能量消耗敏感的 CRSN路由问题,揭示了 CRSN路由问题的独特性,并将这类问题表述为在能量约束和变化的网络拓扑环境下的网络寿命优化问题。在回顾传感器网络的典型算法之后,提出一种新的路由度量来克服 CRSN的路由设计挑战,即认知能量度量(CE)。在此基础上,提出一种分布式路由算法以延长网络寿命,同时提高数据传输的可靠性。仿真结果表明,所提路由算法能很好地适应 CRSN中可用信道资源及网络拓扑的随机变化。  相似文献   

3.

Energy conservation is the main issue in wireless sensor networks. Many existing clustering protocols have been proposed to balance the energy consumption and maximize the battery lifetime of sensor nodes. However, these protocols suffer from the excessive overhead due to repetitive clustering resulting in high-energy consumption. In this paper, we propose energy-aware cluster-based routing protocol (ECRP) in which not only the cluster head (CH) role rotates based on energy around all cluster members until the end of network functioning to avoid frequent re-clustering, but also it can adapt the network topology change. Further, ECRP introduces a multi-hop routing algorithm so that the energy consumption is minimized and balanced. As well, a fault-tolerant mechanism is proposed to cope up with the failure of CHs and relay nodes. We perform extensive simulations on the proposed protocol using different network scenarios. The simulation results demonstrate the superiority of ECRP compared with recent and relevant existing protocols in terms of main performance metrics.

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4.
Routing protocols could achieve efficient convergecast transmission of sensed data in cognitive radio sensor network (CRSN),and it is of vital importance for the whole network performance.In particular,cluster-based routing protocols could further lower routing selection complexity and improve scalability.Therefore,an overview of cluster-based routing protocols for CRSN was provided.Firstly,after a brief introduction to the concept and advantages of clustering in CRSN,the major factors concerning clustering algorithm design were pointed out.Secondly,the challenges faced by routing protocol design in CRSN and basic design principles were explored.Thirdly,the previous work of cluster-based routing protocols for CRSN was systematically analyzed and summarized.Finally,issues that require urgent solutions and future research directions were suggested.  相似文献   

5.
Dhanalakshmi  B.  SaiRamesh  L.  Selvakumar  K. 《Wireless Networks》2021,27(2):1503-1514
Wireless Networks - In this work, a new protocol is proposed for sender-based responsive techniques on energy, mobility, and effective routing for Wireless Sensor Networks (WSNs). It addresses...  相似文献   

6.
Cognitive radio sensor network (CRSN) is an intelligent and reasonable combination of cognitive radio technology and wireless sensor networks. It poses significant challenges to the design of topology maintenance techniques due to dynamic primary-user activities, which in turn decreases the data delivery performance of the network as well as it’s lifetime. This paper aims to provide a solution to the CRSN clustering and routing problem using an energy aware event-driven routing protocol (ERP) for CRSN. Upon detection of an event, the ERP determines eligible nodes for clustering according to local positions of CRSN nodes between the event and the sink and their residual energy levels. Cluster-heads are selected from the eligible nodes according to their residual energy values, available channels, neighbors and distance to the sink. In ERP, cluster formation is based on relative spectrum awareness such that channels with lower primary user appearance probability are selected as common data channels for clusters. For data routing, ERP employs hop-by-hop data forwarding approach through the CHs and primary/secondary gateways towards the sink. Through extensive simulations, we demonstrate that the proposed ERP provides with better network performances compared to those of the state-of-the-art protocols under a dynamic spectrum-aware data transmission environment.  相似文献   

7.
Wireless sensor network of regular topology is efficient in area covering and targets locating. However, communications with fixed channels lead to low spectrum efficiency and high probability of conflicts. This paper proposes economical timeslots‐and‐channels allocation methods for scheduling links in square, triangle, and hexagon lattice topologies. Based on these scheduling methods in square lattice, the authors explore routing methods for load balance and delay minimization, respectively, and compare their effects on transmission delay and energy consumption. The OMNet++‐based simulation for square lattice verified the effectiveness of scheduling methods for improving network throughput and made performance comparison among different scheduling methods. It also proved that delay minimization‐oriented routing helps to reduce the energy consumption for node standing by and load balance‐oriented routing helps to reduce the energy consumption for packets transmission. However, there is trade‐off between the reductions of the two types of energy consumptions. The authors further propose the idea of hybrid routing with the two aforementioned routing methods for reducing overall energy consumption and explore the challenges and countermeasures for hybrid routing optimization. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   

8.
Wireless Networks - The increasing usage of wireless sensor networks in human life is an indication of the high importance of this technology. Holes in wireless sensor networks are non-operating...  相似文献   

9.
Kumar  Ranjit  Tripathi  Sachin  Agrawal  Rajeev 《Wireless Networks》2022,28(7):2913-2936
Wireless Networks - The openness nature of the Ad-hoc sensor networks emerged as a security threat in this network environment that leads to packets drop, network overhead, high range energy...  相似文献   

10.
设计认知无线网络路由算法时,需要兼顾主用户保护与路由性能两个方面。为了提高认知无线网络中次用户之间路由的端到端性能,提出了基于无线电环境地图的路由优化机制,该机制中无线电环境地图能够为次用户提供主用户保护有关的无线电环境数据。首先,无线电环境地图根据次用户的数据请求将各授权频段的可用概率与功率控制相关信息反馈到该次用户;其次,次用户可以计算出与上一跳次用户之间的链路稳定性以及传输时延;最后,目的次用户通过计算每条路由的端到端吞吐量的期望值,然后选取期望值最大的一条路由。仿真结果表明,该路由机制在平均分组投递率、平均端到端吞吐量、平均端到端时延方面均优于对比路由算法。  相似文献   

11.
Routing in a cognitive radio network operating in a dynamic environment is a complex decision problem. Diversity in the number of available spectrum bands and their stability, in addition to the secondary users' heterogeneities, affect the consequence of the routing decision. We use a decision theory framework to model the problem of routing under uncertainties involved in a cognitive radio network. A utility function is designed to capture the effect of spectrum measurement, fluctuation of bandwidth availability, and path quality. A node cognitively decides its best candidate among its neighbors by utilizing a decision tree. Each branch of the tree is quantified by the utility function and a posterior probability distribution that predicts the suitability of available neighbors. In decision tree cognitive routing (DTCR), nodes learn their operational environment and adapt their decision‐making accordingly. We compared our scheme with the optimal performance in a highly dynamic environment and local coordination‐based routing and spectrum assignment protocol [1]. Our results show that the DTCR tends to perform near optimum. It easily adapts to environmental dynamics. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   

12.
Sensornet deployments of the future are expected to deliver a multitude of services, ranging from reliable sensing, real time streams, mission critical support, network reprogramming and so on. Naturally, no one routing protocol can sufficiently cater to the network layer functionalities expected. Severe resource constraints further limit the possibility of multiple routing protocols to be implemented. Further, vertically integrated designs of present protocols hinder synergy and code-reuse among implementations. In this paper, we present an architecture that allows applications to send different types of flows, often with conflicting communication requirements. A flow’s requirements are made visible to our framework by using just 3 bits in the packet header. The core architecture is a collection of highly composable modules that allows rapid protocol development and deployment. We show that our framework can provide: (i) flow based network functionality that ensures each flow gets an application specific network layer which is dynamically knit as per the flow’s needs, (ii) modular organization that promotes code-reuse, run time sharing, synergy and rapid protocol development and (iii) pull processing that allows flows to dictate their traffic rate in the network, and implement flexible scheduling policies. This creates a framework for developing, testing, integrating, and validating protocols that are highly portable from one deployment to another. Using our framework, we show that virtually any communication pattern can be described to the framework. We validate this by gathering requirements for one real world application scenario: predictive maintenance (PdM). The requirements are used to generate a fairly complete and realistic traffic workload to drive our evaluation. Using simulations and 40 node MicaZ testbed experiments, we show that our framework can meet the deployments demands at granularities not seen before in sensornets. We measure the costs of using this framework in terms of code size, memory footprints and forwarding costs on MicaZ motes.  相似文献   

13.
水下无线传感网络UWSNs被认为是监测海洋最有前景的技术。然而,声信道特性给UWSNs的数据采集提出了挑战。提高UWSNs数据采集效率的有效方式就是融合水下声通信和高动态网络拓扑的特性,设计高性能的路由协议。为此,提出基于地理-机会的水下无线传感网的混合路由,记为GOHR。在GOHR协议中,源节点先计算候选转发节点集,并计算集内每个节点的归一化权重值,再依据归一化权重值对集内节点进行排序,并形成转发节点簇。然后,计算每个簇的期望权重值,最后,选择期望权重值最大的簇内节点作为数据包转发节点。为了避免簇内节点转发数据包时发生碰撞,设置定时延时转发机制。仿真结果表明,提出的GOHR协议提高了数据包传递率,降低了数据包的传输时延。  相似文献   

14.
Wireless sensor networks consist of small battery powered devices with limited energy resources. Once deployed, the small sensor nodes are usually inaccessible to the user, and thus replacement of the energy source is not feasible. Hence, energy efficiency is a key design issue that needs to be enhanced in order to improve the life span of the network. Several network layer protocols have been proposed to improve the effective lifetime of a network with a limited energy supply. In this article we propose a centralized routing protocol called base-station controlled dynamic clustering protocol (BCDCP), which distributes the energy dissipation evenly among all sensor nodes to improve network lifetime and average energy savings. The performance of BCDCP is then compared to clustering-based schemes such as low-energy adaptive clustering hierarchy (LEACH), LEACH-centralized (LEACH-C), and power-efficient gathering in sensor information systems (PEGASIS). Simulation results show that BCDCP reduces overall energy consumption and improves network lifetime over its comparatives.  相似文献   

15.
A survey on routing protocols for wireless sensor networks   总被引:33,自引:0,他引:33  
Kemal  Mohamed 《Ad hoc Networks》2005,3(3):325-349
Recent advances in wireless sensor networks have led to many new protocols specifically designed for sensor networks where energy awareness is an essential consideration. Most of the attention, however, has been given to the routing protocols since they might differ depending on the application and network architecture. This paper surveys recent routing protocols for sensor networks and presents a classification for the various approaches pursued. The three main categories explored in this paper are data-centric, hierarchical and location-based. Each routing protocol is described and discussed under the appropriate category. Moreover, protocols using contemporary methodologies such as network flow and quality of service modeling are also discussed. The paper concludes with open research issues.  相似文献   

16.
Bin Guo  Zhe Li 《Wireless Networks》2009,15(4):423-430
The clustering is a key routing method for large-scale wireless sensor networks, which effective extends the lifetime and the expansibility of network. In this paper, a node model is defined based on the structure and transmission principle of neuron, and a dynamic-clustering reactive routing algorithm is proposed. Once the event emergences, the cluster head is dynamic selected in the incident region according to the residual energy. The data collected by the cluster head is sent back to the Sink along the network backbone. Two kinds of accumulation ways are designed to increase the efficiency of data collection. Meanwhile through the fluctuation of action-threshold, the cluster head can trace the changing speed of incident; the nodes outside the incident region use this fluctuation to send data periodically. Finally, the simulation results verify that the DCRR algorithm extends the network’s lifetime considerably and adapts to the change of network scale. The analysis shows that DCRR has more prominent advantages under low and middle load.
Zhe LiEmail:
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17.
为了延长采用电池供电的无线传感器网络的生命周期,提出了一种综合考虑单个节点能耗和节点传输信息至汇集节点所需总能耗的路由算法.该算法首先根据网络中节点到汇集节点从小到大的距离顺序选择待规划节点,然后计算各对应候选节点的评价参数,该参数由单节点能耗和节点传输信息至汇集节点所需总能耗加权得到,最后选择评价参数最小的候选节点作为待规划节点的中继节点.仿真结果表明,该算法的生命周期明显长于LEACH(Low Energy Adaptive Clustering Hier-archy)算法.  相似文献   

18.
Energy saving and effective utilization are an essential issue for wireless sensor network. Most previous cluster based routing protocols only care the relationship of cluster heads and sensor nodes but ignore the huge difference costs between them. In this paper, we present a routing protocol based on genetic algorithm for a middle layer oriented network in which the network consists of several stations that are responsible for receiving data and forwarding the data to the sink. The amount of stations should be not too many and not too few. Both cases will cause either too much construction cost or extra transmission energy consumption. We implement five methods to compare the performance and test the stability of our presented methods. Experimental results demonstrate that our proposed scheme reduces the amount of stations by 36.8 and 20% compared with FF and HL in 100-node network. Furthermore, three methods are introduced to improve our proposed scheme for effective cope with the expansion of network scale problem.  相似文献   

19.
Tree routing (TR) is a low-overhead routing protocol designated for simple, low-cost and low-power wireless sensor networks. It avoids flooding the network with path search and update messages in order to conserve bandwidth and energy by using only parent–child links for packet forwarding. The major drawback of TR is the increased hop-counts as compared with more sophisticated path search protocols. We propose an enhanced tree routing (ETR) strategy for sensor networks which have structured node address assignment schemes. In addition to the parent–child links, ETR also uses links to other one-hop neighbours if it is decided that this will lead to a shorter path. It is shown that such a decision can be made with minimum storage and computing cost by utilizing the address structure. Detailed algorithms for applying ETR to ZigBee networks are also presented. Simulation results reveal that ETR not only outperforms TR in terms of hop-counts, but also is more energy-efficient than TR.  相似文献   

20.
Telecommunication Systems - Queueing models play a significant role in analysing the performance of power management systems in various electronic devices and communication systems. This paper...  相似文献   

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