【作者】 陈磊；

【导师】 谈振辉；

【作者基本信息】 北京交通大学 ， 通信与信息系统， 2014， 硕士

【摘要】 无线体域网是新一代的无线网络,在医疗、救援、军事等领域有着非常广泛的应用前景,它的主要组成单元为传感器节点,负责数据信息的采集、处理和传输。传感器节点通常是由电池供电,能量十分有限,因此,降低传感器节点的能量消耗,延长生存周期对无线体域网就显得非常关键。在无线体域网中,媒体访问控制(Media Access Control, MAC)协议决定着传感器节点使用无线信道的方式,为传感器节点分配有限的无线信道资源,对无线体域网的性能有着重要的影响。因此,研究设计低能耗的MAC协议,对提高无线体域网的性能有着非常现实的意义,本文将分别从设置优先级和休眠机制两个角度对无线体域网中的MAC协议进行优化。首先,本文介绍了无线体域网的研究背景和关键技术,分析了无线体域网MAC协议的研究现状和设计MAC协议的原则,并重点介绍了基于Wake Up Radio的MAC协议,该协议采用在传感器节点上附加一个低能耗的唤醒模块来控制节点的休眠与激活。进而,本文通过对业务类型、传感器节点设置优先级以及简化紧急业务数据传输流程等方式,对基于Wake Up Radio的MAC协议进行了优化,优化后的MAC协议在降低无线体域网的能量消耗方面取得了不错的效果,提高了无线体域网的能效性。其次,本文针对现有无线体域网MAC协议设计中普遍采用的传统休眠进行了优化。构建了马尔科夫链随机模型,引入了能耗和时延代价矩阵,通过采用线性规划的方法解决了有约束条件的最优化问题,进而得到了使得能耗取得最小值的最优决策。根据最优决策来决定传感器节点在下一时刻进入休眠或者激活状态,避免节点在激活和休眠状态之间频繁转换所带来的能量消耗,进而达到了降低传感器节点的能量消耗,延长节点的电池使用寿命,提高无线体域网整体网络性能的目的。最后,本文总结了无线体域网MAC协议的研究现状,提出了进一步工作的展望。更多还原

【Abstract】 ABSTRACT:Wireless Body Area Network is a new generation of wireless networks, which has a very wide range of application in the medical, rescue, military and other fields. Sensor node is the main component unit, through which collecting, processing and transmitting data information. Sensor node is usually powered by battery, whose energy is very limited, and therefore, reducing the energy consumption of sensor node to extend the life cycle of the wireless body area network becomes very critical. In the wireless body area network, the media access control (MAC) protocol decides the allocation of limited wireless channel resources of sensor nodes, which has an important influence of the performance of the wireless body area network.Therefore, the study of designing low-power MAC protocol to improve the performance of wireless body area network has a very great sense. The thesis will optimize the MAC protocol of wireless body area network respectively from the angles of setting priorities and sleep mechanism.First of all. the research background and key technologies of wireless body area network are first introduced in this paper, the state of the wireless body area network MAC protocol research and principles of designing MAC protocol are analyzed, and then the thesis mainly introduces the wake up radio MAC protocol, in which low cost wake up radio module attached with sensor node controls the sleep and wake of the sensor nodes. Furthermore, the thesis optimizes the MAC protocol through setting priority of the type of services and sensor nodes, and aslo simplifying the process of data transmission in emergency operations, the optimized MAC protocol based wake up radio has been proved to reduce the energy consumption of wireless body area network to improve the energy efficiency of the network.In the second place, the thesis optimizes the traditional sleeping mechanism commonly used in the current MAC protocols of wireless body area network. In this paper, Markov chain stochastic model is established, energy consumption and time delay cost matrix are also introduced. And then, The optimization strategy is got through the using of linear programming to solve the optimization problem with constraints, in which, the minimum of energy consumption has been achieved. It is the optimization strategy that determines the sensor node activating or entering the sleep state at the next time. In this way, energy consumption of sensor node is decreaseed by preventing frequently switching in active and sleep state, consequently, getting a lower power consumption and prolonging the lifetime of the node sensor, advancing the performance of wireless body area network.Finally, the thesis draws conclusions by summarizing situation of wireless body area network MAC protocol and by presenting directions for future work.更多还原