【作者】 李雅芳；

【导师】 黄本雄；

【作者基本信息】 华中科技大学 ， 通信与信息系统， 2007， 硕士

【摘要】 家庭网络是在家庭范围内,将电脑、家电、自动化设备、安全系统、照明系统等相连接并接入互联网的一种新兴网络形式,现已成为网络市场的最新热点和发展方向。IEEE802.15.4/Zigbee技术是一种适合家庭网络的无线技术,它针对低速无线个人区域网,把低能量消耗、低速率传输、低成本作为重点目标,为个人或者家庭范围内不同设备之间低速互连提供统一的标准。本文介绍了IEEE802.15.4的协议标准,包括协议框架、网络拓扑、协议功能等。从超帧结构、数据传输模型、帧类型、能量消耗和安全服务等方面对协议的功能作了具体的描述,并对CSMA-CA(冲突避免的载波多路侦听技术)竞争访问机制和GTS(时隙保证)非竞争访问机制的实现作了详细的阐述。本文研究了IEEE802.15.4的组网过程,介绍协议中的重要原语、常量和属性值的意义与功能,为网络组网的实现奠定基础,并针对家庭网络所需的星型拓扑结构,从信道扫描、网络协调器建立、网络节点关联、数据传输以及解关联等方面对组网的实现进行分析与建模。本文详细分析了组网中节点关联的过程,对其进行进一步的仿真与研究,得出协议的非直接传输方式所需原语数较多,节点加入网络的时间较长。本文给出一种改进的关联流程,这种关联流程减少协议的冗余信令和节点加入网络的延迟,避免了不必要的冲突。最后通过仿真对协议流程和改进流程进行比较,得出节点关联过程的原语数减少了31%,关联时间减少了84%。当多个节点在较短时间内都进行关联操作时,改进流程的优势更加显著。这种改进流程能在家庭网络中得到很好的应用。更多还原

【Abstract】 Home network is a new network form in family region, connecting computer, household appliances, automation equipment, security system, illumination system access to Internet. It becomes the latest hot point and development direction in network market. IEEE802.15.4/ Zigbee technology is one of wireless connection technology suitable for home networking. It aims at low-rate wireless personal area network and makes low energy consumption, low transmission rate, and low cost as key objectives. It provides uniform standard for low data rate wireless connectivity among different devices in personal or family regions.This paper introduced the architecture, network topology and functions of IEEE802.15.4 standard. It also made specific description of superframe structure, data transmission model, frame type, energy consumption and safety, expounded the implement of carrier sense multiple access with collision avoidance (CSMA-CA) channel access and the allocation of guaranteed time slots (GTS).The paper studied the networking of IEEE802.15.4, described the function of the important primitives, constants and attributes, it analyzed and modeled the improvement of star network from five aspects: channel scan, PAN coordinator establishment, association, data transmission and disassociation.The paper analyzed the association flow in detail, made further research and simulation to find that the transmission in non-direct way requires a longer association time. The paper advanced an improving method to reduce redundant primitives, decrease association delay and avoid collision. The comparion of the simulation result of IEEE 802.15.4 and the improving method shows that the number of association primitives decreased 31%, the association time decreased 84%. The advantage of improving method would be more obvious when large quantity of nodes associate in a short time. It could also be well applied in home network.更多还原