UWSNs中基于深度的抑制空洞路由优化算法

针对传统的水下无线传感器网络(UWSNs)的位置路由存在路由空洞问题,提出了基于深度的抑制空洞路由(DSVR)的UWSNs路由协议.DSVR协议通过融合跳数、物理距离和邻居数多个指标决策路由.为了提高通信可靠和缓解路由空洞,DSVR协议选择具有最小跳数路径、最少邻居数的节点作为下一跳转发节点.同时,DSVR协议利用定时器抑制冗余数据包.仿真结果表明:提出的DSVR协议能有效地提高数据包传递率,并降低端到端传输时延以及能耗.     

一种改进的基于最少信道切换的路由算法

在Ad Hoc网络中,如何基于多信道有效地利用网络中的频谱资源,提高网络的性能,已经成为近几年来研究的热点。在DSDV路由协议的基础上,提出了一种基于减少网络中的信道切换的路由算法——OLCH-DSDV,该算法采用最小切换时延的信道分配策略,尽量减少信道切换产生的时延,从而降低了网络时延,提高了吞吐量。该算法要求源节点通过自身维护的路由和信道使用信息,选择到达目的节点的最优路径,也就是需要最少信道切换的路径。仿真结果表明该路由改进算法在有效提高系统吞吐量的同时,也有效地减少了网络中的传输时延。     

基于链路质量的认知无线电网络路由研究

针对认知无线电网络中多信道特性,提出了一种基于链路质量的多信道路由协议。该协议在充分利用频谱集合、提高网络吞吐量的同时,缩短了传输时延。给出了路由指标的具体计算过程,在选路的同时进行频段分配,使可用信道达到有效分配,并在降低时延的同时提高了网络吞吐量。仿真实验证明了该算法的有效性。     

无线Mesh网络联合信道分配和路由协议研究

设计合理的联合信道分配和路由协议对多信道无线Mesh网络的性能至关重要。在分析多网卡多信道无线Mesh网络中联合信道分配和路由协议特点和研究现状的基础上,提出了一种与按需路由协议结合的联合信道分配算法,通过选择最小干扰信道来优化信道分配;同时采用了一种适应多信道多网卡网络的路由判据方法,该方法考虑了信道干扰、接口切换以及路径跳数三个关键因素。仿真结果表明,文中所采用的协议能较为明显地提高网络吞吐量及减小分组的端到端时延。     

无线Mesh网络中一种分布式路由方案

在多射频多信道无线Mesh网络中,链路负载和节点位置的变化将导致网络性能的下降。针对此问题,在混合无线网状路由协议反应式路由基础上,设计了一种新的混合信道分配的分布式路由算法。该算法在路由建立的同时可实现以数据流为单位的最优信道分配,且能避免因单节点失效导致整个网络崩溃的危险。仿真结果表明,提出的RHCA算法较传统算法在网络吞吐量和端到端平均时延方面均有显著优势。另外,在节点移动场景下,所提出的分布式路由算法较其他方法能获得更高的吞吐量和更好的稳健性。     

基于信道选择的认知无线网络路由协议

为保证认知无线网络路由的稳定性,减少信道切换次数,降低端到端时延,提出基于信道选择的路由协议。以信道可用概率和信道切换时延为信道选择标准,在确保信道可用的前提下,选择端到端时延最短的路由进行数据传输,提高路由的时延性能和数据投递率。仿真结果表明,与TDRP、PUC-JRCA协议相比,该协议在数据包传输时延、数据投递率方面有明显改善。     

多信道Ad Hoc网络中位置路由协议研究

在Ad Hoc网络中,利用位置信息可以提高路由协议的性能,但目前的基于位置的路由协议主要是在单信道模型下设计的。为了利用多信道的优势,给出了一个综合利用位置信息和多信道模型的路由协议。该路由协议主要思想是用一个信道接收数据,另外一个信道发送数据,减少包传递时延迟。仿真结果表明,给出的路由协议在平均传包率、平均端到端时延以及汇聚吞吐量方面均优于基于单信道和位置信息的路由协议。     

基于时延优化的移动Ad Hoc网络路由算法

TDMA协议基于时隙预留的机制能够用于在移动Ad Hoc网络中提供QoS保证,然而在大规模网络中,该时分通信会带来较大的端到端时延.提出了一种基于时延优化的启发式算法,该算法将时延作为路由代价函数,并充分考虑了阻塞控制.仿真结果表明,相对于传统的基于最短跳数的路由算法,该算法能够大大减小端到端时延,可以为移动网络中实现多媒体应用提供一种有效途径.     

基于最短时延的认知无线电网络安全路由算法

针对认知无线电网络可用频谱动态变化和路由过程中出现的安全问题,提出将最短数据传输时延和高安全等级路由作为选路标准,设计了一种跨层路由选择算法。算法通过优化转发节点个数和各转发节点接收、发送数据信道来减少数据传输时延。通过选择具有高安全级别的转发节点来保证路由的安全性。理论分析表明算法是高效和可行的。它的时间复杂度是O(N2),其中N是拓扑图中节点的个数。     

MANET中有利于信道重用的按需信道分配和路由协议

从信道重用的角度出发,设计出一种简单而有效的按需固定信道分配机制和路由的协议(CA-AODV-R)。该协议将信道分配放到路由层进行,通过在路由发现时的RREQ和RREP中携带信道信息来分配固定信道,避免了MAC层动态信道分配协议(如DCA等)需要频繁地调用信道分配算法的问题。CA-AODV-R使用的固定信道分配算法为把数据信道按编号从小到大排列后按每3个划分为一个小组,同一条路由发现路径上的后继节点分配固定信道时优先在其前驱节点的固定信道所在小组内选择空闲信道。仿真结果表明,CA-AODV-R协议相对于单信道AODV能够大幅度提高网络吞吐量和分组投递率并降低网络的端到端时延。     

认知无线Mesh 网络中QoS 约束的组播路由算法

对认知无线Mesh网络中满足QoS约束的联合组播路由及频谱分配问题进行研究,提出了一个针对该问题的求解框架,包括问题描述、解决方案的表示、适应度函数以及频谱分配算法.基于两种具有代表性的智能计算方法:遗传算法、模拟退火,提出了两种满足端到端延迟约束的组播路由及频谱分配算法GA-MRSA和SA-MRSA.这两种算法追求的目标是最小化组播树信道冲突总数,并且在获得较低的信道冲突数的情况下,还能占用较少的信道.仿真结果表明,所提出的两种算法能够达到预期目标,获得较低的信道冲突总数.     

A high performance optimal dynamic routing algorithm with unicast multichannel QoS guarantee in communication systems

Dynamic routing protocols play an important role in today??s networks. In communication networks, in a current data transmission session, failing nodes and links is a destructor event which loses packets immediately and it can also waste network resources and services seriously. Sometimes failing nodes can disconnect data transmission and, therefore, lost packets must be retransmitted by new session. In this situation, the routing algorithm must discard failed nodes and must repair paths of session by rerouting them. In this case, static routing algorithms and some existing dynamic routing algorithms cannot manage faulty paths fairly and network efficiency is seriously declined. The capability to compensate for topology changes is the most important advantage dynamic routing offers over static routing. An efficient dynamic routing algorithm tries to reroute and change faulty paths without disconnecting sessions and keeps packet transmission in a desirable rate. It is important to tell that a dynamic routing algorithm should provide multi essential parameters, such as acceptable delay, jitter, bandwidth, multichannel paths, virtual channel connections, label switching technology, optimal resource allocation, optimal efficiency in the case of multimedia, and real time applications. This paper proposes a new dynamic framework which transforms static routing algorithms to dynamic routing algorithms. Using the new dynamic framework, this paper constructs an Optimal Dynamic Unicast Multichannel QoS Routing (ODUMR) algorithm based on the Constrained Based Routing (CBR) and Label Switching Technology which is called as ODUMR Algorithm. The performance of ODUMR is analyzed by network simulator tools such as OpNet, MATLAB, and WinQSB. ODUMR produces results better than the existing static and dynamic routing algorithms in terms of necessary parameters.     

Ergodic secrecy rate of two-user MISO interference channels with statistical CSI

This paper considers a two-user multiple-input single-output （MISO） interference channel with confidential messages （IFC-CM）, where the beamforming vectors at the two transmitters are jointly optimized using the closed-form Pareto-optimal parameterization. We prove that artificial noise cannot improve the secrecy rate performance, and coordinated beamforming is secrecy-rate optimal which is achieved by agreeing on the parameters between the two transmitters. We analyze the feasible set of the beamforming parameters that guarantees positiveness of the secrecy rates when the transmitters know only statistical CSI, and then analysis in the ergodic secrecy rate region is discussed. More importantly, we derive the closed form of the ergodic secrecy rates and illustrate the Pareto-optimal structure of the beamforming vectors.     

Energy-aware routing for delay-sensitive underwater wireless sensor networks

The energy reduction is a challenging problem in the applications of underwater wireless sensor networks （UWSNs）. The embedded battery is difficult to be replaced and it has an upper bound on its lifetime. Multihop relay is a popular method to reduce energy consumption in data transmission. The energy minimum path from source to destination in the sensor networks can be obtained through the shortest path algorithm. However, because of the node mobility, the global path planning approach is not suitable for the routing in UWSNs. It calls for an energy-efficient routing protocol for the high dynamic UWSNs. In this paper, we propose the modified energy weight routing （MEWR） protocol to deal with the energy-efficient routing of delay- sensitive UWSNs. MEWR is a low flooding routing protocol. It can tolerate the node mobility in UWSNs and achieve a low end-to-end packet delay. MEWR can provide lower energy consumption than the existing low delay routing protocols through the dynamic sending power adjustment. The simulation results demonstrate the effectiveness of MEWR.     

动态延时的无线多播路由协议

在分析基于共享树的Ad Hoc网络多播路由协议MAODV的基础上,结合能量模型,提出了一种Ad Hoc网络基于动态延时的多播路由协议ECBMR。算法分析和仿真结果显示,在不增加算法复杂性的前提下,ECBMR明显地改善了MAODV协议的延时特性,节点的能量消耗比较均衡,一方面降低了系统的能耗,另一方面有效地延长了网络的存活时间,比较好地解决了Ad Hoc网络能量和延时相互矛盾的问题。     

An on-demand routing protocol for improving channel use efficiency in multichannel ad hoc networks

In wireless ad hoc networks, end-to-end delivery over network is a critical concern for routing protocols. The capacity of routing protocols is constrained by the intra-flow interference introduced by adjacent nodes on the same path, and inter-flow interference generated by nodes from neighboring paths. In this paper, we develop an on-demand routing protocol M-AODV-R that solves the channel assignment, reuse and routing problem jointly. The proposed channel reuse scheme and channel assignment scheme can enhance channel reuse rate. This cross-layer design approach can significantly improve the performance of multichannel ad hoc networks over existing routing protocols. Simulation results show that the proposed routing M-AODV-R can effectively increase throughput and reduce delay, as compared to AODV protocol.     

认知无线Ad Hoc网络干扰约束和能量高效路由算法

为了减少认知无线Ad Hoc网络的传输中断概率,实现频谱和能量高效,提出一种干扰约束和能量高效（Interference Constraints and Energy-Efficient,ICEE）的路由算法。信道检测除了基于认知节点（Cognitive Radio,CR）对主用户（Primary Users,PU）的干扰约束外,还增加了CR节点的数据传输所需持续时间约束,以保证CR节点在有效利用空闲信道的同时减少传输中断事件的发生,减少故障重传所损耗的能量。在设计路由算法时采用了链路能耗和节点寿命作为度量,通过联合最优的链路选择方程实现网络能量高效,并延长网络的生命周期。实验仿真结果表明,相比较认知Ad hoc网络的自适应路由协议,基于联合信道分配和自适应功率控制的路由协议,ICEE算法在数据包平均能耗上分别减少了41.2%和24.5%,并且有效地延长了网络生命周期。     

一种基于OLSR的无人机网络适用路由算法

无人机自组网的高动态特性以及节点能量高度受限的特点,使得传统路由协议难以适用于无人机网络。针对该问题,在OLSR协议的基础上提出一种无人机网络适用路由（UAV-OLSR）算法。依据链路变化情况实现无人机集群状态感知,综合考虑节点能量、节点位置等因素进行节点质量评估。采用多径思想并通过特定的路径度量准则选择较优路径进行数据转发。仿真结果表明,与OLSR和AODV协议相比,UAV-OLSR具有更低的数据包平均传输延迟、更高的数据包投递率以及更好的能量均衡效果,可以延长无人机网络的生存时间。