无线Mesh网络中一种新的路由判据

由于无线Mesh网络特有的性质,网络中的路由判据设计对网络整体性能起着至关重要的作用。文章介绍了无线Mesh网对路由判据的要求,分析了现有的几种路由判据,并针对现有路由判据的缺点提出了一种新的判据——链路累积干扰．通过仿真对该判据进行了验证。仿真结果说明,新的路由判据能明显改善网络性能。     

一种快速可靠的无线传感器网络路由

针对无线传感器网络的特点,本文提出了一种快速可靠的无线传感器网络路由,采用建立网络树结构方式,使各节点拥有唯一的传输路径,降低网络延迟,减少能量消耗。该路由对硬件无特别要求,仅采用普通射频芯片即可以同时工作于任务查询方式及事件驱动方式,并具有较强的路径自我修复能力。算法通过软件仿真并与经典的路由协议Directed Diffusion做多方面比较,结果表明,该路由具有更好的性能,兼备低延迟,低功耗、鲁棒性强及易实现等特点。     

Energy-efficient routing for mobile agents in wireless sensor networks

In wireless sensor networks, data fusion (in-network processing) is a critical issue because sensor networks are energy-constrained and bandwidth-constrained. Recently, a new scheme based on mobile agent has been proposed to solve the problem. The order and number of nodes on the route traversed by a mobile agent determine the energy consumption, and hence, they have a significant impact on the overall performance of the whole system. Considering the limited transmission range of sensor nodes, we showed that this routing problem in a multi-hop cluster could be modeled as a node-weighted traveling tourist problem (TTP). We proved that the problem was nondeterministic polynomial time (NP)-complete. Then we presented a new approximation algorithm to solve the problem. Simulation experiments demonstrate that the proposed heuristic is more energy-efficient than the two earlier ones. Translated from Journal of Shanghai Jiaotong University, 2006, 40(3): 520–523 [译自: 上海交通大学学报]     

无线传感器网络GPSR路由协议研究

随着定位技术的发展,基于地理位置的路由协议受到广泛的关注与研究。分析了无线传感器网络中地理位置路由协议GPSR的特性,详细阐述了GPSR协议中的贪婪转发及信标发送机制,遇到路由空洞时的局部优化问题,边界转发中所使用的右手法则和平面拓扑图的构造以及边界转发的实现等问题。     

一种电力通信网最大不相交双路由配置方法

针对现有电力通信网路由算法不能为业务分配双路由的问题,提出一种最可靠环路策略下的最大不相交双路由算法(the maximally disjoint routing algorithm under the most reliable loop strategy, MRMLS)。研究了公共通信网中三种类型的双路由算法,考虑了双路由算法可能面临的网络结构,阐述了采用最大不相交双路由算法的必要性。分析了最大不相交双路由的可靠性,并采用最可靠环路策略完成最大不相交双路由的分配工作。改进了原有最大不相交双路由算法,使所提算法充分考虑节点与链路的可靠性。仿真实验将MRMLS与其他两种方法进行对比,验证了MRMLS的可行性与有效性。     

无线传感器低功耗路由算法

为了使无线传感网络维持在小的路由信息的同时进一步降低无线传感网络节点能耗,提出了一种改进的LEACH算法。该算法采用多跳路通信方式,对簇头与sink节点的通信过程中的节点能耗进行优化。为了避免能量过低的节点被作为簇首的情况,在每一轮的簇首选举过程中,节点剩余能量成为选举簇头节点的重要指标。然后用MATLAB进行仿真,实验证明,与经典LEACH算法相比,改进LEACH算法网络能量消耗更加均衡,使网络的生存时间有很大程度上的提高。     

Optimal routing and wavelength assignment for survivable multifibre WDM networks

Multifibre optical networks use a bundle of fibres to realize a link between two optical nodes. Such networks can offer significant economic benefits over single-fibre networks because of their ability to relax the restrictions imposed by the wavelength continuity constraint and their potential for handling future growth. This paper introduces two new and efficient integer linear program (ILP) formulations for dynamic wavelength allocation in survivable multifibre wavelength-division multiplexing (WDM) networks, using dedicated and shared protection. Single-fibre networks, both with and without wavelength conversion, can be treated as a special case of these formulations. The new formulations have been tested on several well-known WDM networks, and the results have been compared to those for single-fibre networks. A simple heuristic for dynamic lightpath allocation is also proposed, and its performance is validated by a comparison of the results to optimal solutions generated by the ILPs. Experimental results demonstrate that the new ILPs are feasible for current networks under low-to-medium traffic. For very large or highly congested networks, the heuristic can be used.     

基于分层拓扑模型的配电网故障定位优化算法

随着配电网规模的不断扩大 ,配电网中的电源点及T接点的数量不断增多 ,配电网故障定位的实时性矛盾将日益突出。针对此问题 ,提出了基于分层拓扑模型的配电网故障定位优化算法。该算法充分考虑配电网故障定位的特点 ,采用分层拓扑模型 ,利用对分法 ,通过计算某一区间中间层顶点故障信息状态组合情况 ,以确定故障所属的更小区间 ,逐步压缩并逼近故障所属区间 ,实现故障的快速、准确定位。     

General synthesis techniques for coupled resonator networks

This article presented general techniques for the synthesis and design of coupled resonator filters. The synthesis of the prototype circuit focuses on the compatibility between the coupling topology and the filtering function to be realized, providing some guidelines to select a proper coupling topology and to solve the coupling matrix synthesis problem. The dimensioning of the distributed filter is centered on parameter extraction techniques.     

基于分层拓扑模型的配电网故障定位优化算法

随着配电网规模的不断扩大，配电网中的电源点及T接点的数量不断增多，配电网故障定位的实时性矛盾将日益突出。针对此问题，提出了基于分层拓扑模型的配电网故障定位优化算法。该算法充分考虑配电网故障定位的特点，采用分层拓扑模型，利用对分法，通过计算某一区间中间层顶点故障信息状态组合情况，以确定故障所属的更小区间，逐步压缩并逼近故障所属区间，实现故障的快速、准确定位。     

A controllable multi‐replica routing approach for opportunistic networks

Opportunistic networks take full advantage of opportunistic encounters among nodes to transfer packets. According to the characteristics of the limited energy of nodes and the frequent link variation in opportunistic networks, we introduce a novel routing metric that comprehensively takes into consideration the energy consumption of nodes, the probability of relay nodes meeting their destination, the time‐to‐live of the packet, and the approximate number of packet copies. Based on this metric, we propose a controllable multi‐replica routing approach in which a single‐branch diffusion strategy is applied to achieve the goal of dynamically controlling the number of replicas of packets. Our simulation results show that the proposed approach can avoid excessive load on individual nodes, guarantee the energy fairness among nodes, prolong the network lifetime, and effectively improve the delivery ratio of packets. © 2017 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.     

A distributed routing algorithm for data aggregation in wireless sensor networks

Considering the impact of aggregation cost on the performance of aggregation routes in wireless sensor networks, an aggregation-decision-based distributed routing algorithm for data aggregation is proposed. When source nodes arrive or leave, the algorithm can calculate the aggregation benefit according to data correlation, aggregation cost and transmission cost. Then the algorithm will adaptively make aggregation and routing decisions based on aggregation benefit. Therefore, it can jointly optimize the aggregation and transmission costs and reduce the energy consumption for data gathering. This distributed algorithm makes all the decisions only relying on the local information. Hence, the routing maintenance cost is limited. Simulation results show that the energy consumption difference between this distributed online algorithm and the previous offline one is within 17% under any network conditions. __________ Translated from Journal of Beijing University of Posts and Telecommunications, 2007, 30(1): 9–13 [译自: 北京邮电大学学报]     

ASAR: An ant-based service-aware routing algorithm for multimedia sensor networks

Aimed at three basic services (event-driven, data query and stream query), the paper presents a QoS routing model for multimedia sensor networks. Moreover, based on the traditional ant-based algorithm, we propose an ant-based service-aware routing (ASAR) algorithm. The ASAR chooses suitable paths to meet diverse QoS requirements from different kinds of services, thus maximizing network utilization and improving network performance. Finally, extensive simulation is conducted to verify the effectiveness of our solution and we give a detailed discussion on the effects of different system parameters. Compared to the typical routing algorithm in sensor networks and the traditional ant-based algorithm, our ASAR algorithm has better convergence and significantly provides better QoS for multiple types of services in the multimedia sensor networks. __________ Translated from Acta Electronica Sinica, 2007, 35(4): 705–711 [译自: 电子学报]     

Routing and wavelength assignment in hierarchical WDM networks

A new routing and wavelength assignment method applied in hierarchical wavelength division multiplexing (WDM) networks is proposed. The algorithm is called offline band priority algorithm (offline BPA). The offline BPA targets to maximize the number of waveband paths under the condition of minimum number of wavelengths, and solve the routing and wavelength assignment (RWA) problem with waveband grooming to reduce cost. Based on the circle construction algorithm, waveband priority function is introduced to calculate the RWA problem. Simulation results demonstrate that the proposed algorithm achieves significant cost reduction in WDM network construction. __________ Translated from Journal of Shanghai Jiaotong University, 2007, 41 (5): 747–750 [译自: 上海交通大学学报]     

智能配电网通信实时性与可靠性QoS路由机制研究

为建立满足智能配电网通信可靠性要求下的实时性路由机制,需要分析电力配电网结构以及电力配电网通信的无线传感器网络结构特点;给出智能配电网高性能通信无线传感器网络信息传输路径选择模型;分析链路失效模式,对网络节点的延时性、可靠性进行赋权;提出路径选择数学模型,对路径求解并将问题简化;最后对算例及应用实例进行求解。分析结果表明:该模型和算法原理简单、计算方便、判断结果准确,能很好的平衡可靠性与实时性对智能电网无线传感器网络信息传输的影响、可提高智能电网无线传感器网络信息传输的可靠性和实时性。     

Contact modeling and prediction-based routing in sparse mobile networks

Mobile ad-hoc networks (MANETs) provide highly robust and self-configuring network capacity required in many critical applications, such as battlefields, disaster relief, and wild life tracking. In this paper, we focus on efficient message forwarding in sparse MANETs, which suffers from frequent and long-duration partitions. Asynchronous contacts become the basic way of communication in such kind of network instead of data links in traditional ad-hoc networks. Current approaches are primarily based on estimation with pure probability calculation. Stochastic forwarding decisions from statistic results can lead to disastrous routing performance when wrong choices are made. This paper introduces a new routing protocol, based on contact modeling and contact prediction, to address the problem. Our contact model focuses on the periodic contact pattern of nodes with actual inter-contact time involved, in order to get an accurate realization of network cooperation and connectivity status. The corresponding contact prediction algorithm makes use of both statistic and time sequence information of contacts and allows choosing the relay that has the earliest contact to the destination, which results in low average latency. Simulation is used to compare the routing performance of our algorithm with three other categories of forwarding algorithm proposed already. The results demonstrate that our scheme is more efficient in both data delivery and energy consumption than previously proposed schemes.     

WSNs中基于代理机制的移动Sink路由算法

在移动无线传感器网络中,提高数据发送成功率和减小网络能量消耗是移动Sink路由协议研究的重点.提出一种基于代理机制的数据传输协议(ABR),论证了利用“代理节点足迹链”在提高数据发送成功率方面的优越性;采用节点位置收敛和直接更新相结合的Sink节点位置更新策略,有效平衡网络能耗与传输时延的矛盾.仿真结果表明ABR在提高网络性能方面有很大的优势.     

A cross-layer design and ant-colony optimization based load-balancing routing protocol for ad-hoc networks

In order to periodically reassess the status of the alternate path route (APR) set and to improve the efficiency of alternate path construction existing in most current alternate path routing protocols, we present a cross-layer design and ant-colony optimization based load-balancing routing protocol for ad-hoc networks (CALRA) in this paper. In CALRA, the APR set maintained in nodes is aged and reassessed by the inherent mechanism of pheromone evaporation of ant-colony optimization algorithm, and load balance of network is achieved by ant-colony optimization combining with cross-layer synthetic optimization. The efficiency of APR set construction is improved by bidirectional and hop-by-hop routing update during routing discovery and routing maintenance process. Moreover, ants in CALRA deposit simulated pheromones as a function of multiple parameters corresponding to the information collected by each layer of each node visited, such as the distance from their source node, the congestion degree of the visited nodes, the current pheromones the nodes possess, the velocity of the nodes, and so on, and provide the information to the visiting nodes to update their pheromone tables by endowing the different parameters corresponding to different information and different weight values, which provides a new method to improve the congestion problem, the shortcut problem, the convergence rate and the heavy overheads commonly existed in existing ant-based routing protocols for ad-hoc networks. The performance of the algorithm is measured by the packet delivery rate, good-put ratio (routing overhead), and end-to-end delay. Simulation results show that CALRA performs well in decreasing the route overheads, balancing traffic load, as well as increasing the packet delivery rate, etc. Translated from Journal of ACTA Electronica Sinica, 2006, 34(7): 1199–1208 [译自: 电子学报]     

宽带接入网技术及其应用

随着数据业务的急剧增长，接入网巳成为全网带宽的最后瓶颈。文章分析了xDSL、HFC、Ethernet、AON、PNO、LMDS等主流宽带接入技术及应用，并指出了宽带接入网的发展方向。     

Detecting the vehicle direction changes for routing algorithms and applications of vehicular ad hoc networks

Vehicular ad hoc networks will enable a variety of applications for safety, traffic efficiency, driver assistance, and infotainment in modern automobile designs. For many of these applications as well as for improving the stability of vehicular ad hoc network routing algorithms, it is necessary to know whether a steering wheel rotation has led to a change in the vehicle motion path. The problem is that some steering wheel rotations are temporary and do not lead to a change in the vehicle motion path. In this paper, a GPS‐free fuzzy sensor is designed for detecting the change of vehicle motion paths. The implementation results show acceptable precision. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.