A Swarming Approach to Optimize the One-Hop Delay in Smart Driving Inter-Platoon Communications

• Published in: Sensors (Basel, Switzerland) Vol. 18; no. 10; p. 3307
• Main Authors: Wu, Qiong, Nie, Shuzhen, Fan, Pingyi, Liu, Hanxu, Qiang, Fan, Li, Zhengquan
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI 01.10.2018; MDPI AG
• Subjects: inter-platoon communications; multi-platoon; one-hop delay; swarming; one-hop delay; inter-platoon communications; multi-platoon; swarming
• ISSN: 1424-8220; 1424-8220
• DOI: 10.3390/s18103307

Multi-platooning is an important management strategy for autonomous driving technology. The backbone vehicles in a multi-platoon adopt the IEEE 802.11 distributed coordination function (DCF) mechanism to transmit vehicles' kinematics information through inter-platoon communications, and then forward the information to the member vehicles through intra-platoon communications. In this case, each vehicle in a multi-platoon can acquire the kinematics information of other vehicles. The parameters of DCF, the hidden terminal problem and the number of neighbors may incur a long and unbalanced one-hop delay of inter-platoon communications, which would further prolong end-to-end delay of inter-platoon communications. In this case, some vehicles within a multi-platoon cannot acquire the emergency changes of other vehicles' kinematics within a limited time duration and take prompt action accordingly to keep a multi-platoon formation. Unlike other related works, this paper proposes a swarming approach to optimize the one-hop delay of inter-platoon communications in a multi-platoon scenario. Specifically, the minimum contention window size of each backbone vehicle is adjusted to enable the one-hop delay of each backbone vehicle to get close to the minimum average one-hop delay. The simulation results indicate that, the one-hop delay of the proposed approach is reduced by 12% as compared to the DCF mechanism with the IEEE standard contention window size. Moreover, the end-to-end delay, one-hop throughput, end-to-end throughput and transmission probability have been significantly improved.