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1.
多宿容迟移动网络适用于物流业物联网等误码率高、频繁中断的环境.然而由于其多宿的特点,其资源分配复杂,难以保证实时性.针对接纳控制过程的资源分配,以效用差分法设计资源分配算法,能够保证过程中的每一步效用单调增加,同时该算法时间复杂度降低到 O (n),可以保证实时性.最后将容迟网络协议框架代码 DTN2和 LTP 植入网络模拟软件 NS2,就节点稀疏的场景进行仿真.实验结果说明算法能够提供较好性能,并同时具有良好的实时性.  相似文献   

2.
与传统网络不同,容迟容断网络(Delay/Disruption Tolerant Networks, DTN)中大部分时间不存在端到端路径,传统的基于中心服务器的各种安全机制在DTN中并不适用,DTN中的数据分发也面临着同样的问题。该文提出了一种完全分布式的安全数据分发机制,采用分布式的基于身份的认证机制,无需中心私钥生成器 (Private Key Generator, PKG)的存在,并且通过门限机制和分类数据名称到分类密钥的映射,节点只需与任意门限个邻居节点通信即可获得所需分类数据的密钥。分析和仿真实验表明,该机制在保证安全性的前提下,与基于移动密钥服务器的方案相比,其密钥获取效率大大提高,非常适合DTN这种环境。  相似文献   

3.
针对深空通信面临的各种问题,对当前深空通信中常用的三种网络协议体系进行了简要介绍,并在此基础上对比三者优缺点,提出其各自的适应场景;阐述了未来深空通信网络面临的困难与挑战;剖析容迟容断网络体系架构,并介绍了DTN网络应用研究进展;列举深空通信网络DTN协议体系中的关键技术,例举在深空环境中使用DTN协议体系进行通信时面临的诸多问题,并展望未来深空通信中DTN的应用前景。  相似文献   

4.
为了有效利用和公平分配有限的网络资源,从而优化网络性能,提高社会福利,该文提出了一种效用及实时业务QoS联合保证的资源分配方案,将效用模型与具有不同服务质量需求的业务相结合,引入需求带宽和期望带宽,建立优化模型。方案不仅体现了资源分配效率的要求,达到系统效用的最优,同时优先保证实时业务的QoS要求,并达到QoS保证业务和尽力而为(Best Effort, BE)业务之间的公平分配。仿真结果表明,提出的方案较传统方案有效地提高了系统总效用,实现了面向服务的资源分配目标,优化了网络系统的整体性能。  相似文献   

5.
容迟容断网络的移动性、间歇连通性和动态拓扑等动态特性使得当前应用于静态网络拓扑和固定多播容量的静态随机网络编码难以适应DTN网络环境的网络编码传输,为此提出了一种DTN网络环境下动态随机网络编码传输方法。该方法以马尔科夫信道模型为基础,根据节点的数据状态动态监测信道速率,在信源节点构造了带信道容量的网络流图,并计算和预测当前网络多播容量,最后根据多播容量的变化动态扩展和裁剪随机网络编码方案,实现DTN网络环境下数据的动态网络编码传输。仿真结果表明,相比传统的固定多播率编码方法,动态随机网络编码方法降低了数据的平均传递延迟,提高了数据投递率。  相似文献   

6.
梁毓惠 《移动信息》2024,46(1):213-216
为进一步探究移动互联网的资源分配问题,文中基于无线互联网通信工况恶劣的特殊情形构建了仿真模型,并结合实际情况,以支持移动边缘计算的服务器为基础,引入基于深度域不变性残差计算的长短期记忆网络(DR-LSTM),从互联网设备任务卸载的角度着手设计了资源分配策略和主要算法流程。通过仿真实验结果可知,基于移动边缘计算的资源分配策略在性能上存在一定的优势,具有潜在的应用价值。  相似文献   

7.
张广驰 《通信技术》2011,44(1):135-136,150
研究半双工正交频分复用(OFDMA)中继网络的资源分配。解决动态子信道分配,自适应功率分配,传输策略选择和中继选择的联合优化问题。为了公平利用中继用户的资源,把中继用户所能帮助的最大子信道数和每个子信道的功率设为常量。在此基础上,提出贪婪算法以最大化总效用。当算法每次分配资源时,把资源分配给潜在效用增长最大的用户。仿真结果表明所提算法与固定的资源分配策略相比,能更高效地利用资源,并且改善了用户间的公平性。  相似文献   

8.
移动环境下互联网接入网络频繁中断,需使用容迟网络协议.然而时间概率不确定性导致DTN路由算法的先验知识计算复杂,文中提出基于空间的路由算法以消除.进一步由接入路由器信息矩阵决定实现接入路由器的k集合,提出广义k选播以缓解概率不确定性,使用效用最大化的规划模型,在整个许可时间段和k个路由器之间进行路由和资源分配,结合DTN的托管传送,可以对多个目的地同时传送数据包.仿真验证了传输性能和鲁棒性整体较优,能灵活支持开放式网络拓扑结构变化.  相似文献   

9.
在社团结构网络模型下,建立社团间多副本数据转发策略的传输概率模型,提出一种基于社团结构的多副本数据传输(CMDD)策略。CMDD策略动态计算社团间移动节点的平均相遇间隔时间,并根据传输概率模型估算借助该社团分发副本可获得的成功传输概率。模拟实验表明,CMDD策略能以较低的传输延迟和较低的传输开销获得较高的数据传输成功率。  相似文献   

10.
一种基于网络编码的移动自组网实时多播协议   总被引:1,自引:1,他引:0  
针对移动自组网中的实时多播场景,提出一种基于网络编码的协议—NCRM.该协议可通过减少网络中数据包的转发次数降低节点能耗,并可改善网络吞吐量性能.为适应实时性要求,在NCRM中引入了严格的时延限制机制.仿真结果显示,与PUMA、MAODV等传统协议相比较,NCRM能更好地适应存在多接收节点、高移动性的环境,且在传输可靠性与节省能耗方面具有显著优势.  相似文献   

11.
This paper proposes efficient resource allocation techniques for a policy-based wireless/wireline interworking architecture, where quality of service (QoS) provisioning and resource allocation is driven by the service level agreement (SLA). For end-to-end IP QoS delivery, each wireless access domain can independently choose its internal resource management policies to guarantee the customer access SLA (CASLA), while the border-crossing traffic is served by a core network following policy rules to meet the transit domain SLA (TRSLA). Particularly, we propose an engineered priority resource sharing scheme for a voice/data integrated wireless domain, where the policy rules allow cellular-only access or cellular/WLAN interworked access. By such a resource sharing scheme, the CASLA for each service class is met with efficient resource utilization, and the interdomain TRSLA bandwidth requirement can be easily determined. In the transit domain, the traffic load fluctuation from upstream access domains is tackled by an inter-TRSLA resource sharing technique, where the spare capacity from underloaded TRSLAs can be exploited by the overloaded TRSLAs to improve resource utilization. Advantages of the inter-SLA resource sharing technique are that the core network service provider can freely design the policy rules that define underload and overload status, determine the bandwidth reservation, and distribute the spare resources among bandwidth borrowers, while all the policies are supported by a common set of resource allocation techniques.  相似文献   

12.
在3G(第3代移动通信系统)中,为了给不同类型的业务提供不同级别的端到端QoS,网络资源必须进行合理分配。QoS和资源分配是密不可分的,而无线资源分配显得尤为重要。文中提出了UMTS的QoS结构,分3部分对空中接口部分的QoS(即无线资源分配策略问题)进行了讨论:首先提出了一种RRA算法,接着讨论了W-CDMA和TD-CDMA系统的无线资源分配问题,最后讨论了下行链路及上行链路的呼叫允许控制(CAC)。  相似文献   

13.
A mobile medical information system (MMIS) is an integrated application (app) of traditional hospital information systems (HIS) which comprise a picture archiving and communications system (PACS), laboratory information system (LIS), pharmaceutical management information system (PMIS), radiology information system (RIS), and nursing information system (NIS). A dynamic resource allocation table is critical for optimizing the performance to the mobile system, including the doctors, nurses, or other relevant health workers. We have designed a smart dynamic resource allocation model by using the C4.5 algorithm and cumulative distribution for optimizing the weight of resource allocated for the five major attributes in a cooperation communications system. Weka is used in this study. The class of concept is the performance of the app, optimal or suboptimal. Three generations of optimization of the weight in accordance with the optimizing rate are shown.  相似文献   

14.
CDMA/TDD移动通信系统的一种信道分配方案   总被引:1,自引:0,他引:1  
未来的CDMA/TDD移动通信系统中存在话音和上下行链路业务量不等的数据业务,使传统的上下行等容量的信道分配方案不再适应业务的要求。提出了一种CDMA/TDD移动通信系统中上下行链路业务量不等时,信道资源分配方案。仿真结果表明,该方案可大大提高系统业务容量。  相似文献   

15.
Scheduling spectrum access and allocating power and rate resources are tasks affecting critically the performance of wireless cognitive radio (CR) networks. The present contribution develops a primal-dual optimization framework to schedule any-to-any CR communications based on orthogonal frequency division multiple access and allocate power so as to maximize the weighted average sum-rate of all users. Fairness is ensured among CR communicators and possible hierarchies are respected by guaranteeing minimum rate requirements for primary users while allowing secondary users to access the spectrum opportunistically. The framework leads to an iterative channel-adaptive distributed algorithm whereby nodes rely only on local information exchanges with their neighbors to attain global optimality. Simulations confirm that the distributed online algorithm does not require knowledge of the underlying fading channel distribution and converges to the optimum almost surely from any initialization.
Georgios B. Giannakis (Corresponding author)Email:

Juan-Andrés Bazerque   (SM’06) received his B.Sc. degree in Electrical Engineering from Universidad de la República (UdelaR), Montevideo, Uruguay in 2003. Since August 2006 he has been working towards the Ph.D. degree as a research assistant with the Electrical and Computer Engineering Department at the University of Minnesota, Minneapolis. From 2000 to 2006 he was a teaching assistant with the Department of Mathematics and Statistics, and with the Department of Electrical Engineering (UdelaR). From 2003 to 2006 he was a member of the technical Staff at the Uruguayan telecommunications company Uniotel S.A. developing applications for Voice over IP. His general research interests span the areas of communications, signal processing and wireless networking with current emphases on distributed resource allocation for cognitive radios. G. B. Giannakis   (Fellow’97) received his Diploma in Electrical Engr. from the Ntl. Tech. Univ. of Athens, Greece, 1981. From 1982 to 1986 he was with the Univ. of Southern California (USC), where he received his MSc. in Electrical Engineering, 1983, MSc. in Mathematics, 1986, and Ph.D. in Electrical Engr., 1986. Since 1999 he has been a professor with the ECE Department at the Univ. of Minnesota, where he now holds an ADC Chair in Wireless Telecommunications. His general interests span the areas of communications, networking and statistical signal processing - subjects on which he has published more than 250 journal papers, 450 conference papers, two edited books and two research monographs. Current research focuses on complex-field and space-time coding, multicarrier, cooperative wireless communications, cognitive radios, cross-layer designs, mobile ad hoc networks and wireless sensor networks. G. B. Giannakis is the (co-) recipient of six paper awards from the IEEE Signal Processing (SP) and Communications Societies including the G. Marconi Prize Paper Award in Wireless Communications. He also received Technical Achievement Awards from the SP Society (2000), from EURASIP (2005), a Young Faculty Teaching Award and the G. W. Taylor Award for Distinguished Research from the University of Minnesota. He has served the IEEE in a number of posts, and is currently a Distinguished Lecturer for the IEEE-SP Society.   相似文献   

16.
未来的TD/CDMA移动通信系统中存活话音及上下行业务量不等、优先级不同的数据业务,为适应新业务的特点,充分发挥TDD/CDMA移动通信系统自身的优势,本文提出了TDD/CDMA移动通信的一种新的信道分配方案。仿真结果表明,该方案可大大降低低优先级业务的掉线概率,充分利用有限的信道资源。  相似文献   

17.
在第三代移动通信的无线资源管理机制中,分组调度机制在保证预期的服务质量(QoS)和优化无线资源的利用率方面起到了至关重要的作用.至今已经有很多的调度算法被提出,用来有效地提高无线网络资源的利用率.本文提出一种基于Eb/No并且利用功率控制和管理机制的无线分组公平调度算法用来保证QoS,优化资源配置并且达到调度公平性.  相似文献   

18.
该文研究了上行 OFDMA 系统中高能效资源分配问题.首先,在考虑数据包重传条件下将多用户上行OFDMA 系统建模成 M/G/1排队系统,该系统的业务服务速率由其分配得到的资源和当前信道共同决定.在业务平均时延约束下,建立了基于业务统计特性的能效资源分配优化模型.该问题为 NP 难问题,文中提出一种启发式算法,将资源分配分为两步进行:子信道数目确定和子信道分配.仿真表明,所提算法能够在保证业务平均时延的要求下,有效地提升系统能效.  相似文献   

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