【作者】 徐斌；

【导师】 冷甦鹏；

【作者基本信息】 电子科技大学 ， 通信与信息系统， 2014， 硕士

【摘要】 车载无线自组织网络(VANET)能够为人们提供安全,舒服,方便的交通服务。IEEE1609系列协议和IEEE802.11p协议共同规定了车载网络的整体协议架构。并且1609.4协议提出车网络采用多信道传输,阐述了信道切换方式。IEEE 1609.4标准规定车载网络MAC层采用多信道传输机制,在SCH时隙具有六个业务信道,1609.4协议并没有明确规定这些信道的具体分配措施。为了提高业务信息的传输性能,本文研究了MAC层多个信道和时间的分配策略,针对车载网络车与路边设施通信交互模式,提出了一种基于节点相对位置及业务类型的资源分配算法。路边设施在接收到节点的业务需求时,能够根据当前节点的位置信息和业务的Qos需要计算出各个节点的优先级,然后在处理相应的业务需求时,需要计算不同分配方法的评价函数值,从中选出需要slot较少,切换信道次数较少和能够保持各个信道负载较为均衡的方法。在车辆密度较大的交通环境中,有限的频带资源可能无法满足节点的业务需求。本文提出了一种车载网络中的接纳控制和信道预留策略,由于车辆在道路上行驶具有一维性,车辆节点的运行状态更容易掌握。RSU对于资源的预留机制预测结果更有意义,预留资源也会更加准确。另外,考虑到车辆节点的运行速度要远远大于移动终端的运行速度,而且车辆的速度和方向随时都会改变,为了提高信道预留准确性,RSU将会根据车辆密度的变化,动态的更新获取到的节点位置信息。从而在保证原有服务不掉线的情况下,尽量的接纳新用户的服务。为了对资源分配算法对车载网络性能的影响做出验证,本文建立了车载网络MAC协议仿真平台。并利用仿真平台验证了基于节点相对位置及业务类型的资源分配算法对于业务信息传输的可靠性,数据包的端到端时延以及系统的吞吐量产生的影响,并与基于空闲信道资源分配算法的仿真结果做出分析和比较。更多还原

【Abstract】 Vehicle wireless ad-hoc network(VANET) can provide people with safe, comfortable, and convenient transportation. International Organization for Standardization IEEE established the IEEE 802.11 p and IEEE 1609 working group co-specification vehicle network research process to develop a protocol standard VANET. In the IEEE 1609.4 standard, the channel is divided into a control channel and service channel, the former security for the transmission of information and control information, while the latter is used to transmit secure information unrelated to business information.IEEE 1609.4 standard vehicle network MAC layer using multi-channel transmission mechanism, SCH slot with six traffic channel, 1609.4 agreement does not specifically assign these measures clearly defined channels. In order to improve the transmission performance of business information, this paper studies the allocation strategy MAC layer multiple channels and time for vehicle network V2 I interactive mode, a new resource allocation algorithm based on the relative position of nodes and business types. Upon receiving the roadside service facilities demand node can be calculated according to the position information and the Qos of the current service priority level of each node in the node, then when the treatment of the corresponding business requirements necessary to calculate the evaluation function value of the different allocation methods, to choose the less need slot, channel switching times, and less able to keep each channel load more balanced approach. In order to ensure reliable, real-time delivery of safety information provided, greatly enhance the transmission performance of the traffic channel.In a large vehicle traffic density environments, the limited bandwidth resources may not meet the business needs of the node. This paper presents an in-vehicle network admission control and channel reservation policy, because the vehicle on the road with a running one-dimensional vehicle easier to master node. RSU resource reservation mechanism for forecasting results more meaningful, reserve resources will be more accurate. Further, considering the running speed of the vehicle is much greater than the node running speed of the mobile terminal, and the speed and direction of the vehicle at any time to change in order to improve the accuracy of channel reservation, RSU will change according to the traffic density and dynamic updates for to node position information. In order to ensure that the existing services are not dropped as far as the admission of new users of the service.In order to influence resource allocation algorithm for on-board network performance validation to make paper on OPNET network simulation software to build a vehicle network MAC protocol simulation platform. And to verify the effect of the use of simulation platform based on the relative position of nodes and business type of resource allocation algorithm for reliability of business information transmission throughput, end to end delay and packet generation systems, and with the idle channel resource allocation algorithm based on simulation results of the analysis and to make comparisons.更多还原