摘要
IEEE 802.11p协议是针对车载无线接入技术制定的MAC层和物理层标准,仍采用二进制指数退避算法,该算法不能根据车辆速度和密度作出调节,在V2I通信中,会造成严重的信道访问不公平和碰撞等现象,无法很好地适用于车载网络。针对上述问题,提出的算法在退避重传阶段,采用固定的最优竞争窗口,并能够根据车速和从路边单元获取的网络信息实时调整竞争窗口大小。模型分析和仿真实验表明,该算法可明显改善信道访问的吞吐量、公平性与可靠性。
IEEE 802.11p protocol is the MAC layer and physical layer standard designed for wireless access in vehicular environment. The backoff algorithm it utilized is Binary Exponential Backoff（BEB）. BEB doesn’t adjust along with the change of the vehicle speed and the network status, which will lead to serious unfairness and collision in vehicle-to-infrastructure communications. So it can’t be well applied to the vehicular network. In order to solve these problems, a novel algorithm is proposed, which uses a constant optimal contention window in backoff process. The contention window can also be adjusted with the vehicle speed as well as the network status got from roadside units. The mathematical analysis and simulation experimental results show that the proposed algorithm in this paper can obviously improve the performance of channel access such as throughput, fairness, reliability and so on.
出处
《计算机工程与应用》
CSCD
北大核心
2016年第14期105-109,135,共6页
Computer Engineering and Applications
关键词
车载自组织网络
车路通信
IEEE
802.11p
公平性
媒体访问控制协议
Vehicular Ad Hoc Networks（VANET）
Vehicle to Infrastructure（V2I）communication
IEEE 802.11p
fairness
Media Access Control（MAC）protocol
作者简介
杨博（1990-）,男,助理工程师,研究领域为车联网技术与应用、无线网络MAC协议设计,E-mail：yang_bo_nudt@163.com;
王杉（1978-）,男,博士,副研究员,研究领域为移动自组织网络、认知无线网络;
石新新（1990-）,男,硕士,研究领域为无线网络MAC协议设计与实现.
