This paper proposes an approach called PC-CORP (Power Control based Cooperative Opportunistic Routing Protocol) for WSN (Wireless Sensor Networks), providing robustness to the random variations in network connectivity...This paper proposes an approach called PC-CORP (Power Control based Cooperative Opportunistic Routing Protocol) for WSN (Wireless Sensor Networks), providing robustness to the random variations in network connectivity while ensuring better data forwarding efficiency in an energy efficient manner. Based on the realistic radio model, we combine the region-based routing, rendezvous scheme, sleep discipline and cooperative communication together to model data forwarding by cross layer design in WSN. At the same time, a lightweight transmission power control algorithm called PC-AIMD (Power Control Additive Increase Multiplicative Decrease) is introduced to utilize the co- operation of relay nodes to improve the forwarding efficiency performance and increase the robustness of the routing protocol. In the simulation, the performance of PC-COPR is investigated in terms of the adaptation of variations in network connectivity and satisfying the QoS requirements of application.展开更多
为解决民航机坪覆盖面积大、设备分布分散以及资源受限导致的消息投递率低、传输时延长以及网络开销大的问题,提出一种机坪感知网络机会控制方法(MPCS)。利用机坪节点接触特性,融合节点多维属性构建节点转发能力模型筛选候选转发节点,...为解决民航机坪覆盖面积大、设备分布分散以及资源受限导致的消息投递率低、传输时延长以及网络开销大的问题,提出一种机坪感知网络机会控制方法(MPCS)。利用机坪节点接触特性,融合节点多维属性构建节点转发能力模型筛选候选转发节点,提高目标跟踪准确度;依据节点分布确定可转发节点数,即消息副本转发数,解决多副本传输开销大问题;结合余弦相似度进一步确定候选转发节点并转发消息,扩大消息传播范围,提高消息投递率。在ONE仿真模拟器的验证结果表明,与传统Epidemic、Prophet和Spray and Wait相比,MPCS策略的消息平均投递率达到80%,消息平均时延低至235 s,表现了相对较好的网络性能。展开更多
针对OFDM无线信道估计中的上行链路与下行链路信号冲突和估计精度低等问题,提出一种适用于正交频分复用(orthogonal frequency division multiplexing,OFDM)无线信道的基于自适应时变的机会信道估计机制。考虑OFDM符号特征、离散信号串...针对OFDM无线信道估计中的上行链路与下行链路信号冲突和估计精度低等问题,提出一种适用于正交频分复用(orthogonal frequency division multiplexing,OFDM)无线信道的基于自适应时变的机会信道估计机制。考虑OFDM符号特征、离散信号串并转换特性和自适应傅里叶变换及其逆变换过程,为优化信道估计复杂度,提出OFDM无线信道模型。基于中继节点集合选取策略和基于多跳无线信道传输的信道估计,提出基于自适应时变的OFDM无线信道机会估计机制。对所提信道估计算法与基于判决反馈的信道估计机制进行实验对比,对比结果表明,所提估计算法可以更好地适应子载波规模和用户规模的动态变化,提供高精度和高吞吐率的无线信道估计。展开更多
机会社会网络(opportunistic social networks)能够利用节点移动创造的相遇机会,在缺乏持续端到端连接的网络中,为用户提供稳定的消息分发途径,但在消息分发效率以及用户体验方面存在不足.为提高消息分发系统的性能、改善网络用户体验,...机会社会网络(opportunistic social networks)能够利用节点移动创造的相遇机会,在缺乏持续端到端连接的网络中,为用户提供稳定的消息分发途径,但在消息分发效率以及用户体验方面存在不足.为提高消息分发系统的性能、改善网络用户体验,提出一种基于节点兴趣匹配的机会社会网络分发机制.通过引入混合结构的机会社会网络分发系统解决网络拓扑信息获取不全与节点计算能力不足的问题;从节点行为规律与兴趣爱好2方面对网络进行分析,并提出一种用于复杂关系数据分析的联合聚类方法;针对用户需求,设计消息属性与节点兴趣匹配优先的消息分发策略.仿真结果表明,该机制能够在投递率、投递时延、缓存占用率等方面提升网络性能,且具有较高的分发效率、覆盖率与兴趣匹配度.展开更多
针对机会网络中由于节点移动、网络稀疏等各种原因通常导致网络拓扑动态变化大,消息源节点到汇聚节点之间往往不存在稳定的端到端的通信链路,提出了一种基于偏好顺序决策法(the technique for order preference by similarity to ideal ...针对机会网络中由于节点移动、网络稀疏等各种原因通常导致网络拓扑动态变化大,消息源节点到汇聚节点之间往往不存在稳定的端到端的通信链路,提出了一种基于偏好顺序决策法(the technique for order preference by similarity to ideal so-lution,TOPSIS)的数据收集策略(data gathering based on the TOPSIS,DGT)。DGT策略根据节点的剩余能量、感知节点到汇聚节点的距离以及传感器节点的连通变化,采用TOPSIS评估选择下一跳中继节点。仿真实验表明,与现有的几种典型转发控制机制相比,DGT策略在保证较低传输延迟和较高传输成功率的基础上,通过减少节点间的转发次数,降低了网络传输开销。展开更多
Based on the analysis of the existing classic clustering routing algorithm HEED, this paper proposes an efficient dynamic clustering routing algorithm ED-HEED. In the cluster selection process, in order to optimize th...Based on the analysis of the existing classic clustering routing algorithm HEED, this paper proposes an efficient dynamic clustering routing algorithm ED-HEED. In the cluster selection process, in order to optimize the network topology and select more proper nodes as the cluster head, the proposed clustering algorithm considers the shortest path prediction of the node to the destination sink and the congestion situation. In the data transmission procedure, the high-efficiency CEDOR opportunistic routing algorithm is applied into the ED-HEED as the data transmission mode between cluster headers. A novel adaptive dynamic clustering mechanism is also considered into the algorithm, as well as the data redundancy and security control. Our Simulation demonstrates that the ED-HEED algorithm can reduce the energy consumption, prolong the network life and keep the security and availability of the network compared with the HEED algorithm.展开更多
基金Supported by 973 Program (2007CB310607)National Natural Science Foundation of China (60772062)the Open Research Fund of National Mobile Communications Research Laboratory, Southeast University (N200813)
文摘This paper proposes an approach called PC-CORP (Power Control based Cooperative Opportunistic Routing Protocol) for WSN (Wireless Sensor Networks), providing robustness to the random variations in network connectivity while ensuring better data forwarding efficiency in an energy efficient manner. Based on the realistic radio model, we combine the region-based routing, rendezvous scheme, sleep discipline and cooperative communication together to model data forwarding by cross layer design in WSN. At the same time, a lightweight transmission power control algorithm called PC-AIMD (Power Control Additive Increase Multiplicative Decrease) is introduced to utilize the co- operation of relay nodes to improve the forwarding efficiency performance and increase the robustness of the routing protocol. In the simulation, the performance of PC-COPR is investigated in terms of the adaptation of variations in network connectivity and satisfying the QoS requirements of application.
文摘为解决民航机坪覆盖面积大、设备分布分散以及资源受限导致的消息投递率低、传输时延长以及网络开销大的问题,提出一种机坪感知网络机会控制方法(MPCS)。利用机坪节点接触特性,融合节点多维属性构建节点转发能力模型筛选候选转发节点,提高目标跟踪准确度;依据节点分布确定可转发节点数,即消息副本转发数,解决多副本传输开销大问题;结合余弦相似度进一步确定候选转发节点并转发消息,扩大消息传播范围,提高消息投递率。在ONE仿真模拟器的验证结果表明,与传统Epidemic、Prophet和Spray and Wait相比,MPCS策略的消息平均投递率达到80%,消息平均时延低至235 s,表现了相对较好的网络性能。
文摘针对OFDM无线信道估计中的上行链路与下行链路信号冲突和估计精度低等问题,提出一种适用于正交频分复用(orthogonal frequency division multiplexing,OFDM)无线信道的基于自适应时变的机会信道估计机制。考虑OFDM符号特征、离散信号串并转换特性和自适应傅里叶变换及其逆变换过程,为优化信道估计复杂度,提出OFDM无线信道模型。基于中继节点集合选取策略和基于多跳无线信道传输的信道估计,提出基于自适应时变的OFDM无线信道机会估计机制。对所提信道估计算法与基于判决反馈的信道估计机制进行实验对比,对比结果表明,所提估计算法可以更好地适应子载波规模和用户规模的动态变化,提供高精度和高吞吐率的无线信道估计。
文摘机会社会网络(opportunistic social networks)能够利用节点移动创造的相遇机会,在缺乏持续端到端连接的网络中,为用户提供稳定的消息分发途径,但在消息分发效率以及用户体验方面存在不足.为提高消息分发系统的性能、改善网络用户体验,提出一种基于节点兴趣匹配的机会社会网络分发机制.通过引入混合结构的机会社会网络分发系统解决网络拓扑信息获取不全与节点计算能力不足的问题;从节点行为规律与兴趣爱好2方面对网络进行分析,并提出一种用于复杂关系数据分析的联合聚类方法;针对用户需求,设计消息属性与节点兴趣匹配优先的消息分发策略.仿真结果表明,该机制能够在投递率、投递时延、缓存占用率等方面提升网络性能,且具有较高的分发效率、覆盖率与兴趣匹配度.
文摘针对机会网络中由于节点移动、网络稀疏等各种原因通常导致网络拓扑动态变化大,消息源节点到汇聚节点之间往往不存在稳定的端到端的通信链路,提出了一种基于偏好顺序决策法(the technique for order preference by similarity to ideal so-lution,TOPSIS)的数据收集策略(data gathering based on the TOPSIS,DGT)。DGT策略根据节点的剩余能量、感知节点到汇聚节点的距离以及传感器节点的连通变化,采用TOPSIS评估选择下一跳中继节点。仿真实验表明,与现有的几种典型转发控制机制相比,DGT策略在保证较低传输延迟和较高传输成功率的基础上,通过减少节点间的转发次数,降低了网络传输开销。
文摘Based on the analysis of the existing classic clustering routing algorithm HEED, this paper proposes an efficient dynamic clustering routing algorithm ED-HEED. In the cluster selection process, in order to optimize the network topology and select more proper nodes as the cluster head, the proposed clustering algorithm considers the shortest path prediction of the node to the destination sink and the congestion situation. In the data transmission procedure, the high-efficiency CEDOR opportunistic routing algorithm is applied into the ED-HEED as the data transmission mode between cluster headers. A novel adaptive dynamic clustering mechanism is also considered into the algorithm, as well as the data redundancy and security control. Our Simulation demonstrates that the ED-HEED algorithm can reduce the energy consumption, prolong the network life and keep the security and availability of the network compared with the HEED algorithm.
