STDMA多跳无线网络分布式时隙共享策略研究

发布时间：2018-09-18 17:33

【摘要】：多跳无线网络泛指所有由自主无线节点相互合作组成的、源节点的数据报文通过多个相继的无线链路以多跳方式传输到对应目的节点的通信网络。由于具有无需大型基础设施支撑、不依赖固定骨干结构、抗毁及自愈能力强等优良特性,多跳无线网络的应用范围不断被扩展。其中,包括无线Ad Hoc网络、无线传感器网络、无线网状网等在内的多跳无线网络的具体表现形式被广泛应用于抢险救灾、环境监控、智能家居、车载通信等众多领域,已成为物联网时代“万物互联”构想的重要依托。多跳无线网络的资源十分有限,从MAC层出发设计有效的链路调度策略从而实现高效率的网络资源分配一直是多跳无线网络研究的热点。现阶段,各类多跳无线网络所承载的业务量逐年增大、种类日益繁多,被802.11协议族所广泛采用的CSMA/CA接入技术逐渐显现出了无法从根本上解决暴露/隐蔽终端问题、数据包间的碰撞概率随着传输跳数的增多呈指数介增长、各传输节点之间的公平性很难得到保证、难以分类保证不同业务流的不同Qo S需求等诸多弊端。因此,学术界和大多数商用公司开始采用基于STDMA预约机制的多跳无线网络来实现多等级Qo S需求的业务传输。然而,虽然STDMA具有可在高负载情况下保障网络吞吐量、便于降低碰撞概率算法寻找、易于保证节点间公平性等的诸多优点,但现有针对多跳无线网络而设计的STDMA协议大多采用静态的时隙调度方案且基于协议干扰模型切割网络的方式不允许位于一定空间范围内的各节点共享时隙,从而导致时隙利用率极为低下。鉴于此,本文将基于资源混合优化(RCO,Resource Combinatorial Optimization)对STDMA多跳无线网络的时隙共享问题展开系统的研究。在归纳总结国内外最新研究成果、深入分析最优化问题数学理论的基础之上,构建可以实现不同网络优化目标的时隙共享问题最优化模型,设计各最优化模型的求解算法,进而依据所得最优解提出多种多项式级时间复杂度时隙共享策略。首先,针对节点可用能量及网络生存时间受限型的STDMA多跳无线网络,开发以功率效率为主要优化目标的时隙共享策略。本文将首先以功率效率最大化为目标函数构建相应时隙共享问题的最优化模型,并证明该最优化模型所描述的数学问题本质。接下来本文将深入探索相应时隙共享问题的物理本质,证明并利用同传链路各发送功率与各链路所用数据速率间的函数关系将所建立的最优化模型等价的降维成一个标准的线性规划问题。然后本文将针对该等价的线性规划问题设计一种反向递归连续动态规划求解方法,并据此求解方法设计一种功率效率最优的功率控制算法。最后,基于该功率控制算法设计一种功率效率最优的时隙共享策略。最后,仿真结果将从吞吐量、误包率、以及功率消耗三个方面综合论证所提出的时隙共享策略的性能优势。其次,针对吞吐量能力受限型的STDMA多跳无线网络,开发可以最优化网络吞吐量的时隙共享策略。本文将把以最大化时隙吞吐量为目标函数的时隙共享问题建模成一个混合整数凸优化问题。鉴于该最优化模型所描述的数学问题为NP困难问题,本文将对有限域STDMA多跳无线网络的最优吞吐量能力进行全方位的剖析,通过一系列定理证明在物理层可提供多速率支持的情况下,有限域STDMA多跳无线网络最优吞吐量能力的存在性及其取得条件,并依靠该取得条件将所建立的混合整数凸优化问题等价的降维成混合整数线性规划问题。然后本文将把该等价后的混合整数线性规划问题构建成背包问题,针对该背包问题设计一种离散动态规划求解方法并据此求解方法设计一种最优链路选择及速率分配算法。最后,基于该算法设计相应吞吐量最优的时隙共享策略并通过NS3验证该时隙共享策略的各方面性能表现。最后,考虑到在网络各节点所用功率增大过程中STDMA多跳无线网络吞吐量能力增长的非均匀特性,开发负载自适应的时隙共享策略。本文将首先对STDMA多跳无线网络整网以及特定时隙内的同传链路上可获得的吞吐量能力随着功率的变化情况做定量性的解析,寻找依据网络负载大小动态调整各节点所用功率及链路数据速率的理论依据。然后基于该理论依据设计一种负载大小自适应的资源混合优化算法,进而依托该算法设计网络负载大小自适应的时隙共享策略,并通过NS3验证该时隙共享策略于不同网络负载大小下的性能表现。最后本文将探讨基于网络负载变化率来调整时隙共享策略调度方案的必要性,设计一种负载变化率自适应的资源混合优化算法,进而依托该算法设计网络负载变化率自适应的时隙共享策略,并通过实验所得数据验证应用该时隙共享策略的最佳负载改变率区间。
[Abstract]:Multi-hop wireless networks generally refer to all communication networks composed of autonomous wireless nodes cooperating with each other, and the data packets of the source nodes are transmitted to the corresponding destination nodes in multi-hop mode through multiple successive wireless links. The applications of multi-hop wireless networks are expanding. Among them, the concrete manifestations of multi-hop wireless networks, including wireless Ad Hoc networks, wireless sensor networks, wireless mesh networks and so on, are widely used in many fields, such as emergency rescue, environmental monitoring, smart home, vehicle-borne communications and so on, and have become the "interconnection of all things" structure in the Internet of Things era. The resource of multi-hop wireless network is very limited. It is a hot topic to design effective link scheduling strategy from MAC layer to realize efficient network resource allocation in multi-hop wireless network. The widely used CSMA/CA access technology gradually shows that it can not fundamentally solve the problem of exposed/concealed terminals. The collision probability between packets increases exponentially with the increase of the number of transmission hops. It is difficult to guarantee the fairness among transmission nodes, and it is difficult to classify and guarantee the different Qos requirements of different traffic flows. Therefore, academia and most commercial companies have begun to adopt STDMA-based multi-hop wireless networks to achieve multi-level Qos traffic transmission. However, although STDMA has many advantages, such as guaranteeing network throughput under high load, reducing collision probability algorithm and ensuring fairness between nodes, STDMA has many advantages. Most of the existing STDMA protocols designed for multi-hop wireless networks adopt static slot scheduling schemes, and the protocol interference model-based cut network does not allow nodes in a certain space to share slots, resulting in extremely low utilization of slots. In view of this, this paper will be based on resource mix optimization (RCO, Resource C). Based on the summary of the latest research results at home and abroad and the in-depth analysis of the mathematical theory of optimization problems, an optimization model for slot sharing problem in STDMA multi-hop wireless networks is constructed, and the optimization models are designed. First, for STDMA multi-hop wireless networks with limited energy availability and network lifetime, a time-slot sharing strategy with power efficiency as the main optimization objective is developed. Next, the physical nature of the corresponding slot sharing problem will be explored in depth, and the optimal model will be proved by using the functional relationship between the transmission power of the simultaneous link and the data rate used in each link. The equivalent dimensionality reduction of the model is transformed into a standard linear programming problem. Then a reverse recursive continuous dynamic programming method is designed to solve the equivalent linear programming problem, and a power control algorithm with optimal power efficiency is designed based on this method. Finally, the simulation results demonstrate the performance advantages of the proposed slot sharing strategy in terms of throughput, packet error rate and power consumption. Secondly, a slot sharing strategy is developed for STDMA multi-hop wireless networks with throughput constraints. The slot sharing problem with maximized slot throughput as an objective function is modeled as a mixed integer convex optimization problem. Considering that the mathematical problem described by the optimization model is NP-hard, this paper will analyze the optimal throughput capability of a finite-field STDMA multihop wireless network in an all-round way and prove it in the physical layer by a series of theorems. The existence of optimal throughput capacity and its acquisition conditions for a finite-field STDMA multi-hop wireless network with multi-rate support are given. Based on this acquisition condition, the mixed integer convex optimization problem is equivalent to a mixed integer linear programming problem. A discrete dynamic programming method is designed to solve the knapsack problem and an optimal link selection and rate allocation algorithm is designed. Finally, a slot sharing strategy with optimal throughput is designed based on the algorithm and the performance of the strategy is verified by NS3. Considering the non-uniformity of the throughput growth of STDMA multi-hop wireless networks in the process of increasing the power used by each node in the network, a load-adaptive slot sharing strategy is developed. Then, a load-adaptive hybrid resource optimization algorithm is designed based on the theoretical basis, and then a load-adaptive slot sharing strategy is designed by relying on the algorithm, and N is used to adjust the network load size dynamically. Finally, this paper will discuss the necessity of adjusting the scheduling scheme of slot sharing strategy based on the network load change rate, and design a load change rate adaptive resource mixing optimization algorithm. The optimal load change rate range of the slot sharing strategy is verified by the experimental data.
【学位授予单位】：哈尔滨工业大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TN929.5

【相似文献】