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1.
基于SCS算法的盲自适应多用户检测器   总被引:2,自引:0,他引:2  
提出了一种基于SCS(Soft-Constraint-Satisfaction)算法的盲自适应多用户检测器。基于SCS算法的盲自适应多用户检测器只需知道期望用户的扩频码及定时信息,而且通过自动选择用来估计期望信号的非线性函数,可以调节算法的收敛速度和估计误差。仿真实验表明该方法具有较好的抗多址干扰的能力。  相似文献   

2.
功率控制下基于能耗最小的Ad hoc网络路由选择算法   总被引:3,自引:3,他引:0  
在节点MAC层发射功率可控情况下,提出了一种基于路径能量消耗最小的路由路径选择算法。该算法根据链路的能量消耗情况来进行路由路径选择,达到节约网络能量的目的。仿真表明.该算法可以动态调整网络路由路径,从而使所选路径的能量消耗达到最小。  相似文献   

3.
自适应有源噪声控制的滤波-LMAD算法   总被引:1,自引:0,他引:1  
本文研究了稳定非高斯环境下的自适应有源噪声控制问题,提出了滤波-LMAD(leastmeanabsolutedeviation)算法及归一化滤波-LMAD算法,仿真结果表明,与常用的滤波-LMS算法和归-化滤波-LMS算法相比,本文提出了算法收敛速度更快。  相似文献   

4.
一种基于模糊的MUSIC改进算法   总被引:1,自引:0,他引:1  
王德明 《电子学报》1996,24(8):83-86
本文将模糊控制理论应用于高分辨谱估计测向中,提出MUSIC算法的改进算法,我们称为Fuzzay-MUSIC算法,以解决短数据,低信噪比下谱估计测向问题,并给出了在TMS320C30仿真开发系统上计算机的模拟结果。  相似文献   

5.
提出了一种基于平均分组时延与分组能量消耗乘积最小的路由路径选择算法。该算法根据路径的平均分组时延和分组能量消耗情况来进行路由路径选择。仿真表明,该算法可以动态调整网络路由路径,使所选路径的平均分组时延与分组能量消耗乘积达到最小。  相似文献   

6.
文章给出n-维超立方体网络的容错路径选择算法,该算法具有自适应性,可以防止死锁和活锁现象的发生,应用该算法,可求出一条基于安全优先策略的可行最短路径。  相似文献   

7.
作者在文献〖4〗中提出了一种改进的瞬变步长SPLMS自适应滤波算法。本文在SPLMS算法的基础上,进一步提出一种基于瞬变步长、瞬变平滑因子的双瞬变SPLMS算法-DSPLMS算法。该算法除具有常规LMS算法简单的优点外,还具有更高的起始收敛速率、更小的权失调噪声和更大的抑噪能力.文中重点讨论了瞬变步长、瞬变平滑因子的变化特性。计算机仿真结果支持了理论分析。  相似文献   

8.
多用户检测中盲自适应算法的研究   总被引:2,自引:0,他引:2  
王艺  薛强 《电讯技术》2000,40(1):37-40
多用户检测中的盲目适应算法包括上输出能量(MOE)算法、Sato算法、恒模算法(CMA)和约束恒模算法(C-CMA)。本文比较了以上算法和均方误差(MSE)算法的收敛性能,仿真表明在保证收敛的条件下,CMA或C-CMA算法具有收敛速度快、稳态性能好的优点,因此实际系统中可以先脾MOE算法,当达到稳态后,转到CMA或C-CMA算法上以提高稳态性能,且计算复杂度只有O(N)。  相似文献   

9.
徐志军  王晓军 《数字通信》1998,25(3):15-16,27
设计了一种可变速率的低时延、码激励线性预测编码(LD-CELP)的方案,它是通过修改码本来实现的。该方案工作在11.2kbit/s。对其做了计算机仿真,并与16kbit/s的LD-CELP算法在信经(SNR)、波形等方面进行了对比,仿真结果表明效果良好。  相似文献   

10.
研究了一种面向算力网络的多路径低时延转发调度算法。该算法可以根据网络状态变化动态更新路径价值量生成路径转发决策,并在一定置信概率内以多路冗余发包的方式进行多路备份传输,降低路径传播时延。还提出了一种等级与队列映射算法,利用网络可编程技术改进设备转发逻辑,利用有限数量严格优先队列保障数据包近似按等级出队,降低数据排队时延。仿真实验结果表明,所提出方法可以降低数据传输时延及抖动,为算力网络业务提供稳定吞吐量。  相似文献   

11.
A localized adaptive proportioning approach to QoS routing   总被引:1,自引:0,他引:1  
In QoS routing, paths for flows are selected based on knowledge of resource availability at network nodes and the QoS requirements of flows. Several QoS routing schemes have been proposed that differ in the way they gather information about the network state and select paths based on this information. We broadly categorize these schemes into best path routing and proportional routing. The best path routing schemes gather global network state information and always select the best path for an incoming I-low,based on this global view. It has been shown that best path routing schemes require frequent exchange of network state, imposing both communication overhead on the network and processing overheads on the core routers. On the other hand, proportional routing schemes proportion incoming flows among a set of candidate paths. We have shown that it is possible to compute near-optimal proportions using only locally collected information. Furthermore, a few good candidate paths can be selected using infrequently exchanged global information and thus with minimal communication overhead. We describe these schemes in detail and demonstrate that proportional routing schemes can achieve higher throughput with lower overhead than best path routing schemes  相似文献   

12.
Energy-aware routing is important in multi-hop wireless networks that are powered by battery, e.g., wireless sensor networks. To maximize the network survivability, the energy efficiency of paths must be taken into account for route selection. Simple heuristics such as choosing paths with minimal energy consumption are ineffective, because the energy of the nodes on such paths may deplete quickly. The issue is particularly serious for the networks with regular traffic pattern as in monitoring sensor applications. Existing solutions to this issue typically adopt the multi-path routing approach, in which multiple paths are set up between source and destination and one (or all) of the paths is (are) used at a certain moment. However, this approach involves high overhead for establishment and management of multiple paths. In this paper, we present a static single-path routing scheme which uses one energy-efficient path for each communicating peer throughout the network lifetime, eliminating the overhead of multi-path routing. It is theoretically proved that our routing scheme achieves a constant factor approximate of the optimal solution. We compare the performance of the proposed scheme with that of multi-path routing via simulations. Despite the use of single static path, the proposed scheme outperforms existing multi-path routing schemes and produces performance close to the optimal multi-path solution, particularly in heavily loaded networks and multiple-gateway networks.  相似文献   

13.
Path length, path reliability, and sensor energy-consumption are three major constraints affecting routing in resource constrained, unreliable wireless sensor networks. By considering the implicit collaborative imperative for sensors to achieve overall network objectives subject to individual resource consumption, we develop a game-theoretic model of reliable, length and energy-constrained, sensor-centric information routing in sensor networks. We define two distinct payoff (benefit) functions and show that computing optimally reliable energy-constrained paths is NP-Hard under both models for arbitrary sensor networks. We then show that optimal length-constrained paths can be computed in polynomial time in a distributed manner (using O(E) messages) for popular sensor network implementations using geographic routing. We also develop sensor-centric metrics called path weakness to measure the qualitative performance of different routing schemes and provide theoretical limits on the inapproximability of computing paths with bounded weakness. Heuristics for computing optimal paths in arbitrary sensor networks are described along with simulation results comparing performance with other routing algorithms.  相似文献   

14.
Distributed quality-of-service routing in ad hoc networks   总被引:10,自引:0,他引:10  
In an ad hoc network, all communication is done over wireless media, typically by radio through the air, without the help of wired base stations. Since direct communication is allowed only between adjacent nodes, distant nodes communicate over multiple hops. The quality-of-service (QoS) routing in an ad hoc network is difficult because the network topology may change constantly, and the available state information for routing is inherently imprecise. In this paper, we propose a distributed QoS routing scheme that selects a network path with sufficient resources to satisfy a certain delay (or bandwidth) requirement in a dynamic multihop mobile environment. The proposed algorithms work with imprecise state information. Multiple paths are searched in parallel to find the most qualified one. Fault-tolerance techniques are brought in for the maintenance of the routing paths when the nodes move, join, or leave the network. Our algorithms consider not only the QoS requirement, but also the cost optimality of the routing path to improve the overall network performance. Extensive simulations show that high call admission ratio and low-cost paths are achieved with modest routing overhead. The algorithms can tolerate a high degree of information imprecision  相似文献   

15.
为了降低光组播路由 的光域网络编码代价和提高达到理论最大光组播容量的 概率,提出一种基于共享链路和网络编 码的优化光组播容量方法。首先设计一种从多条源- 宿最短路径中选择能达到最大光组播容量的最短路径簇,然后在 最短路径簇中计算路径的共享度,选择共享度高的组播路径传输网络编码信息,构造网络编 码次数最少的光组播编码子图, 解决传统的网络编码组 播路由和最大共享度链路组播路由中存在的网络编码次数过多和达到最大光组播容量概率过 低的问 题。仿真结果表明:本文提出的方法具有最低的网络编码代价,能以最大的概率达到光组播 理论最大容量。  相似文献   

16.
Huang  Haojun  Pan  Shengli  Zhang  Junbao 《Wireless Networks》2022,28(3):1335-1347
Wireless Networks - Multipath routing, which provides multiple paths for ubiquitous communications, has been considered as promising routing mechanism to optimize network performance for Internet....  相似文献   

17.
A taxonomy of rerouting in circuit-switched networks   总被引:1,自引:0,他引:1  
In circuit-switched networks it is well known that dynamic routing can provide significant throughput gain over fixed routing. Rerouting is the practice of routing calls currently on alternate paths to direct paths or other less congested alternate paths. Previous studies have shown that rerouting can not only increase the throughput of dynamic routing, but also maintain network stability without the need for trunk reservation. This article presents a taxonomy of rerouting in circuit-switched networks showing the various ways rerouting can be designed. In addition, a comparative study on a number of rerouting schemes are performed in a uniformly loaded, fully connected circuit-switched network  相似文献   

18.
无线Ad hoc网络机会路由的实现与仿真   总被引:1,自引:1,他引:0  
在无线自组织网络中,路由协议对网络的性能起着关键性作用。然而由于无线信道的不稳定性经常造成通信中断而需重建路由,使自组织网传统路由协议的效率大大降低。提出了一种应用于无线自组织网络的机会路由协议(WAOR),利用无线信道的广播特性和多径传输来增强链路的可靠性。采用网络仿真器NS2的仿真结果表明,WAOR的性能优于传统的动态源路由协议(DSR)和自组织网按需平面距离矢量路由协议(AODV)。  相似文献   

19.
Dynamic routing has been adopted in circuit-switched networks in many parts of the world. Most of the routing algorithms used are least loaded routing (LLR) based for its simplicity and efficiency. Rerouting is the practice of routing calls on alternate paths back to direct paths or to other less congested alternate paths. It allows the continuous redistribution of network loads for the relief of the congestion on direct paths. In this paper, we present an original analysis of an LLR-based rerouting scheme. Through numerical examples and confirmation by computer simulation, the throughput gain of rerouting is established  相似文献   

20.
Layer 2 network technology is extending beyond its traditional local area implementation and finding wider acceptance in provider's metropolitan area networks and large-scale cloud data center networks. This is mainly due to its plug-and-play capability and native mobility support. Many efforts have been put to increase the bisection bandwidth in layer 2 network, which has been constrained by the spanning tree protocol (STP) that layer 2 network uses for preventing looping. The recent trend is to incorporate layer 3's routing approach into layer 2 network so that multiple paths can be used for forwarding traffic between any source-destination (S-D) node pair. Equal cost multipath (ECMP) is one such example. However, ECMP may still be limited in generating multiple paths due to its shortest path (lowest cost) requirement. In this paper, we consider a non-shortest-path routing approach, called equal preference multipath (EPMP) based on ordered semi group theory, which can generate more paths than ECMP. In EPMP routing, all the paths with different traditionally-defined costs, such as hops, bandwidth, etc., can be determined equally now and thus they become equal candidate paths. By the comparative tests with ECMP, EPMP routing not only generates more paths, provides 15% higher bisection bandwidth, but also identifies bottleneck links in a hierarchical network when different traffic patterns are applied. EPMP is more flexible in controlling the number and length of multipath generation. Simulation results indicate the effectiveness of the proposed algorithm. It is a good reference for non-blocking running of big datacenter networks.  相似文献   

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