Information theory based performance analysis and enhancement of safety applications in DSRC

Dedicated short-range communication (DSRC) is an enabling technology for Intelligent Transportation Systems (ITS). Due to lack of stable topology, the periodic and event-driven safety applications take broadcast as an effective approach to disseminate messages, which leads to significant performance degradation in high density and highly dynamic scenarios. This paper presents an information theory based model to determine the theoretical amount of information required by DSRC safety applications, and the results are helpful in reducing redundant information in performance enhancement as well as gaining more insight for system design. Based on the model presented, an adaptive algorithm is proposed to derive the optimal safety message rate in different scenarios to reduce the channel load. Numerical simulations based on NS-3 show the proposed algorithm can improve the performance dramatically, and the effectiveness of the safety applications is guaranteed.