无线公交车载网络切换机制研究

Research on the Handoff Mechanisms for Wireless Bus Networks

为公交车乘客提供高质量的Internet服务可以让其在乘车过程中享受娱乐及工作,进而大大提高乘客的生活质量。基于此,本文针对公交车载网络的切换问题进行研究。首先提出一种改进的公交车载网络结构,进而提出一种基于数据传输速率的切换触发机制。该机制可以准确触发切换,减少切换开销,改进通信稳定性。针对公交站点存在多个访问点的切换场景,本文进一步提出一种合适的切换策略-M-Handoff。M-Handoff以负载均衡为目标进行访问点选择,同时可以保证各个已连接的公交车辆的平均吞吐率。仿真实验表明,与传统方法相比,以上机制可以较好地提高系统性能,能更好地适于公交车载通信。

Providing high quality Internet services in public buses allows the bus passengers to entertain themselves and even to work remotely during their travel time,thus significantly improving their quality of life.This paper focuses on the handoff mechanisms for bus networks.Firstly,a data transmission rate based handoff trigger is proposed based on an improved bus network structure.The trigger can be fired for a handoff accurately with low cost and high communication stability.Further,an adaptive handoff mechanism called M-Handoff is studied for the scenario in which there exist multiple APs（Access Points） in a bus station.The mechanism aims to guarantee load balancing in all APs to execute AP selection and also can achieve high average bus throughput for each associated bus.Through simulation experiments,the above mechanisms can improve system performance more greatly and support bus communication better than the traditional methods.