车联网中RSU动态接入选择问题的研究

Research on Dynamic Access Selection of RSU in VANET

车联网中车与车以及车与基础设施间的实时通信问题越来越受到关注,而车辆的高速移动性和无线通信的不可靠性大大降低了数据传输效率。为了解决这个问题,针对路边单元(Road Side Unit, RSU)接入选择问题进行了研究,并提出了一种新的RSU接入选择算法,来合理调配车辆与RSU的连接。车辆选择RSU进行接入的常规方法是基于车辆的接收信号强度,但它未充分考虑车辆的高速移动性,这会导致接入RSU的车辆的数目大幅度变化。所以采用实时监测和预测相结合的方法合理调配RSU上连接的车辆,让每一RSU上连接的车辆数目波动幅度达到最小,并且保证RSU得到充分利用。仿真结果表明,此算法能够有效降低数据包碰撞、增强无碰撞传输概率、提高成功传包率。

Real-time communication problems of vehicle to vehicle and vehicle to infrastructure in VANET(Vehicular Ad hoc Network, VANET) have been taken more and more attention by researchers. The high speed mobility of vehicles and the unreliability of wireless communication greatly reduced the efficiency of data transmission. In order to solve this problem, the attention is focused on the dynamic access selection of RSU(Road Side Unit, RSU) in VANET and a new RSU selection algorithm is proposed to allocate vehicles access to related RSUs. The conventional access method is based on the signal strength of vehicles received from related RSU, but it does not take full account of the high speed mobility of vehicles which will lead to a vast variability of number of vehicles connected to RSU. In this paper, a method of real-time monitoring and forecasting is used to adjust certain vehicle connect on reasonable RSU to make the load of each RSU as much as balance, which will minimize the variability of the number of vehicles connected to each RSU, and ensure the RSU can be fully utilized. Simulation results show that the proposed algorithm can reduce the message collision, enhance the probability of collision free transmission, and improve the successful packet transmission rate effectively.