Reduction of V2V Packet Collision Due to Traffic Concentration in Integrated V2V/I2V ITS Communication System

Integrated Vehicle to Vehicle (V2V) and Infrastructure to Vehicle (I2V) intelligent transportation systems (ITS) communication system is under research and development for achieving safe driving. The system employs time-division multiplexing technique for accommodating V2V and I2V communications with single radio channel. Both communications use CSMA/CA for transmit broadcast packets. However, it causes concentration of radio traffic at the beginning of V2V communication period and frequent packet collisions happen. This paper proposes a method of reducing packet collision due to traffic concentration for V2V communication. It divides vehicle stations into groups and assigns them different time frames dedicated to the groups. Network simulations assuming 100 vehicles in a cross road was conducted. The obtained results show that the packet delivery rate is remarkably improved by the proposed method.